CA 02374576 2002-03-14
77316-13D
MULTI-PURPOSfi AIRCRAFT
Technical Field
The presort im~endon relates to general aviation aircraft. More particularly,
the present invention
relates oo a novel aircraft adaptable to recreational, utility, or business
uses and disdaguished by design
features permitting fuselage expansion a~ in-flight alteration of its
configuration.
Background Art
Many different types of aircraft have bees desig~d to melt, within the limits
of airworthiness,
the particular requiremenrs of fliers. Thus, aircraft designs and design
modifications are well known
which wiD permit aircraft to land on different surfaces, such as ski-type
landing gear for lardungs on
snow, hull-type fuselage and pontoons for amphibious landings. and wing
designs having inct~sed wing
sur6ce areas and shapes for takeoff and landing in short distances. Stroukoff,
for instance. described in
U.S. 2.844,339 retractable sld landing gear added to as aircraft having
renxtiag tricycle wheel gear,
however the added slti components were not integrated with the wheel gear and
did not lend the capability
of coordinated movement, to meet the demands of a variety of landing surlaca.
Some f~au~es have also been developed that pemvit modification of err
aircraft's configuration
2 0 (and thus its flight charactctistics) while in flight. For example, some
jet fighter aircraft are often
equipped with wing panels that are rotated out from the fuselage to increase
wing span and lower stall
spud for takeoffs and landings but are swept back during flight to increase
ma~ttvenbility and decrease
drag and bending stresses.
Although the adaptability of an aircraft to differcat uses and to different
flight and landing
2 5 conditions is always desirable, most design modifications that shit as
aircraft to a particular spaialized use
necessitate design compromises that adversely affect the sirrraft's
performance in some other aspect. For
instance, amphibious aircraft designs have been limited by the necessity of
placing the engine high over
the wing, to avoid ianerference with the propeller by the spray of waoer from
takeoff or landing. This is a
design compromise that crates a high thrust lip for the aircraft gad also
additional drag.
3 0 Also, the sign sopbistication and sa~mral reqturemeats necessary to adopt
such capabiyities as
'swing" wings are umpractical and expensive for private rxreatioml aircraft.
Accordingly, there is a continuing need for the development of aircraft that
are suited to a variety
of uses gad which can satisfy the requirements and damands of a wide variety
of commercial and
recreational fliers.
CA 02374576 2002-03-14
77316-13D
-2-
a is as object of the present invention, therefore, to provide a novel twin-
engine
propeller-driven aircraft (although many feadires of this invention will be
applicable to jet-
powered aircraft and to aircraft having any number of engines).
It is a further object of the present invention to provide a basic aircraft
design that can
be adapted to serve a wide variety of specialized uses without entailing
modification of the
design or extensive refitting.
It is a further object of the present invernion to provide a basic aircraft
design capable of
a wide range of uses but without imroducing design compromises that limit or
reducx specific
flight performance characteristics.
It is a further object of the present invention to provide an aircraft capable
of landing on
snow, water or land without pre-flight modific~ion of the laadiag gear.
It is a further object of the present invention to provide a short takeoff sad
landing
(STOL) aircraft having a high degree of maneuverability and capabk of trimming
drag and
decreasing wing surface area sad wing span in flight.
It is a further objax of the present iron to provi~ a beak design for an
aircraft
that is expandable from 2 seats to 8 or more seats without entailing redesign
of the airfoil or
fuselage.
It is a further object of the present invention to provide a basic design for
an aircraft
2 0 chat is convertibk fra~m a passenger-carrying configuration to a
eargo~eawying configuration (or
to other spxialized cabin configurations) without entailing redesign of the
airfoil or fuselage.
it is a further objax of the present invention to provide a novel landing gear
design
integrating skin. w6eela, and pantoo~, which can be converted to the
appropriate configuration
during flight.
2 5 It is a further object of the present inveadon to provide a propellor-
driven, mufti-engine
airtxaR with improved safety cltuameriatics. Ia particular, it is an object of
the invention to
provide >iraaft of unprxed~ safety through an aircraft design which eliminates
many of the
leading causes of aviad~ accidents. including asymmetrical thrust c~ditioos
due to an engine
failure, propeller blade separation (i.e., loss of a propeller due to damage
to the propelkr blades
3 0 and rive reaultirtg vibration and breakage), rapid power lose (engine
failure) during takeoff or
climbovt, inappropriate configuration or selation of landing gear. and
accidents related to the
position of the propeller on an aircraft on the ground (e.g., uniatatciooal
eoatxxs with ground
objats or people).
It is a further objat of the present invention to provide a novel propeller
drive system
3 5 for a propeller-driven aircraft and to provide an aircraft design
characterized by unifying
CA 02374576 2002-03-14
77316-13D
- 3 -
mounting structures for the propellers and landing gear,
allowing adjustment of propeller position relative to the
airfoil as a function of landing configuration of the aircraft.
It is a further object of the present invention to
provide a 2-8 seat aircraft that is easy to service and
maintain and which maintains airworthiness in a variety of
emergency situations.
These and other objects are accomplished herein by a
novel type of aircraft and novel components thereof having a
l0 number of innovative design features including: telescoping
wing extensions; integrated multiple landing gear mounts
permitting skis, wheels, or pontoon outriggers to be rotated
into landing position, at the option of the pilot; modular
fuselage sections permitting the addition of seats or cargo
area without requiring redesign or refitting of wing or tail
components; propellers mounted on their own shafts which are
belt-driven from inboard engines; a primary structure
permitting support of the engine mass by the fuselage
structures rather than the wings and permitting large fuselage
openings for easy engine access, efficient cargo handling,
enhanced pilot visibility, or enhanced passenger comfort.
Utilization of one or more of these features provides an
aircraft of improved safety, performance, reliability,
efficiency, and versatility over aircraft currently available.
One broad aspect of the invention provides an
aircraft capable of takeoff from and landing on snow or a hard
surface, comprising: a wing structure; a fuselage (300); a
forward landing gear assembly moveable relative to said fuselage
(300) during flight from a first position retracted within said
fuselage (300) to a second position extended from said fuselage
(300), said forward landing gear assembly comprising a steerable
forward wheel assembly (21, 193, 203, 230, 316) and a steerable
forward ski assembly (29, 193, 203, 230, 316), said forward
CA 02374576 2002-03-14
77316-13D
- 3a -
landing gear assembly further comprising a forward landing gear
actuator assembly (191, 197, 198, 201, 204, 205) operable by the
pilot of the aircraft during flight which selectively deploys
said steerable forward wheel assembly (21, 193, 203, 230, 316)
or said steerable forward ski assembly (29, 193, 203, 230, 316)
to said extended second position for landing, said forward
landing gear actuator assembly comprising a positioning assembly
(190, 197, 198, 201, 230) for deploying and retracting said
forward wheel assembly and said forward ski assembly relative to
l0 said fuselage (300), a ski deployment actuator assembly (204,
205, 206, 207, 208, 209) for positioning the forward ski gear
assembly relative to the forward wheel assembly, whereby control
of the extension of said ski deployment actuator assembly
determines whether the forward ski gear or the forward wheel
assembly is in the appropriate position to contact the ground
upon landing; and a main landing gear assembly moveable relative
to said fuselage (300) during flight from a first position
retracted within said fuselage (300) to a second position
extended from said fuselage (300), said main landing gear
assembly comprising a steerable main wheel gear assembly (20,
133, 210, 220) and a main ski gear assembly (137, 144, 145, 147,
149) including a pair of skis (147), said main landing gear
assembly further comprising a main landing gear actuator
assembly (130, 137, 138, 141, 215, 216) operable by the pilot of
the aircraft during flight which selectively deploys said
steerable main wheel gear assembly (20, 133, 210, 220), or said
main ski gear assembly (137, 144, 145, 147, 149) relative to
said main wheel gear assembly, said main landing gear actuator
assembly comprising a main gear connecting link (137), forward
and rear ski supports (144, 145) carrying said main ski gear
assembly pivotally attached to said main gear connecting link
(137), forward and rear positioning actuators (216, 215) for
pivoting said forward and rear ski supports relative to said
main gear connecting link (137), and a main gear mounting
assembly (210, 220) pivotable relative to said main gear
connecting link (137), permitting said main wheel gear assembly
' CA 02374576 2004-07-09
77316-13D
- 3b -
to move relative to said main gear connecting link, whereby
control of the extent of deployment by said main landing
gear actuator assembly determines whether the steerable main
wheel gear or the main ski gear assemblies are in the
appropriate position to contact the ground upon landing;
wherein said main landing gear assembly in said first
position forms an integral part of said fuselage (300) with
said main ski gear assembly forming the exterior surface
thereof, said pair of skis of said main ski gear assembly in
said retracted position forming a substantially flush
surface with said fuselage (300) .
According to another broad aspect, the invention
provides a compound aircraft wing comprising: a fixed wing
section comprising a bilaterally symmetrical aircraft wing
of a fixed length (span) defining leading and trailing edges
and defining port and starboard halves, said fixed wing
section being at least partially hollow, thereby defining an
inner surface and an outer surface of said fixed wing
section, said fixed wing section further being open at the
port and starboard ends, thus forming port and starboard
openings, a port wing extension panel comprising a forward
port lift spar, a center port drag spar, and an aft port
lift spar, which port spars are disposed in parallel
relation and each spar being substantially the same length
as said fixed wing section, substantially one-half the
length of said spars being enclosed by and giving structural
support to an outer skin so as to form a port aircraft wing
extension section ending in a wing tip, said port wing
extension panel being extendably mounted inside said fixed
wing section such that said port wing extension panel is
extendable through the port opening of the fixed wing
section such that substantially all of the port aircraft
wing extension section protrudes from the port end of the
' CA 02374576 2004-07-09
77316-13D
- 3c -
fixed wing section, said port wing extension panel further
being mounted inside said fixed wing section such that said
port wing extension panel is retractable within said fixed
wing section such that substantially all of the port wing
extension panel is enclosed by said fixed wing section, and
a starboard wing extension panel comprising a forward
starboard lift spar, a center starboard drag spar, and an
aft starboard lift spar, which starboard spars are disposed
in parallel relation and each spar being substantially the
same length as said fixed wing section, substantially one-
half the length of said spars being enclosed by and giving
structural support to an outer skin so as to form a
starboard aircraft wing extension section ending in a wing
tip, said starboard wing extension panel being extendably
mounted inside said fixed wing section such that said
starboard wing extension panel is extendable from the
starboard opening of the fixed wing section such that
substantially all of the starboard aircraft wing extension
section protrudes from the starboard end of the fixed wing
section, said starboard wing extension panel further being
mounted inside said fixed wing section such that said
starboard wing extension panel is retractable within said
fixed wing section such that substantially all of the
starboard wing extension panel is enclosed by said fixed
wing section, said port wing extension panel and said
starboard wing extension panel being mounted in such
relation that said port spars and said starboard spars are
in interlocking juxtaposition inside the fixed wing section.
Brief Description of the Drawinqs
Figure 1 is a perspective view of an aircraft
according to the present invention, showing telescoping wing
sections and landing gear fully extended. The aircraft is
CA 02374576 2004-07-09
77316-13D
- 3d -
shown in a configuration advantageous for takeoff and
landing on a hard surface.
Figure 2 is a perspective view of an aircraft
according to the present invention as illustrated in
Figure 1 but with an alternative, conventional tail design
(as opposed to the "T" tail shown in Figure 1).
Figure 3 is a perspective view of an aircraft
according to the present invention, with the propeller
mounts and landing gear retracted. The aircraft is shown
shortly after takeoff or in a configuration suitable for
low-speed flight.
Figure 4 is a perspective view of an aircraft
according to this invention as depicted in Figure 3, showing
telescoping wing sections in a fully retracted position.
Figure 5 is a perspective view of an aircraft
according to this invention as depicted in Figure 4, except
that a modular fuselage section has been removed to attain a
shorter fuselage.
Figure 6 is a front elevation view of an aircraft
according to the invention, shown in the hard surface
takeoff and landing configuration similar to Figure 1.
Figure 7 is a front elevation view of the aircraft
as illustrated in Figure 6, but with telescoping wing panels
in a fully retracted position.
Figure 8 is a front elevation view of an aircraft
according to the invention, shown in the configuration
appropriate for takeoff or landing on snow or ice
CA 02374576 2002-03-14
77316-13D
Figure 9 is a front elevuion view of as aircraft according to the invetuioa,
shown in a
configuration appropriate for taheo" .~r landing on wiser.
Figure 10 is a front elevation view of an aircraft as depicted in Figure 9, in
a
configuration appropriate for slow speed water taxiing operation.
Figure 11 is a front elevation view of as aircraft according to the invention,
shown in a
high speed cruise configuration. This is the same configuration as depicted in
Figures 4 and 5.
Figure 12 is a front elevation view of.an aircraft as depicted is Figure 11,
shown in a
low speed configuration. ~ telescoping wing sections fully extended. This is
the same
overall cottfiguruion for the aircraft as illustrated in Figure 4.
Figure 13 is a plan view of an aircraft as depicted in Figures 3 and 12.
Figure 14 is a plan view of an aircraft as depicted in Figures 1, 6, and 8.
Figure 15 is a plan view of an aircraft as depicted is Figures 4 and 11.
Figure 16 is a perspective view of the sta:boar~d wing extension assembly of a
compound wing structure according to the present invention. This figure shows
the internal
supporting beam structures of the extendable wing satin.
Figure 17 is a detail of the encircled portion XVII of Figure 16, showing the
inboard
end of the supporting spars of the extendabk wing section.
Figure 18 is a perspaxive view of t~ starboard wing exteoaion assembly as
depicted in
Figure 16, showing its position relative to the main wing section (shown in
phantom lines) when
2 0 the wing extension panel is fully exa:nded (ref. Figure 13). Thin figure
also shows the
positioning of roller assemblies enabling rolling extension of the wing
extension pawls and
shows the relative position of the support strutxures of a port wing extension
assembly.
Figure 19 is a detail of the encircled portion XDC of Figure 18, showing th a
positioning
of rollers in reluion to the supporting spars for the eatendabk wing section.
2 5 Figure 20 is a paapative view of the starboard wing extrusion assea>bly as
depicted in
Figure 15, showing its position relative to the main wing section (shown in
phantom litres) when
the exteaaion patrol is fully raraaed (ref. Figure 15).
Figures 21, 22, wad 23 show front cross-sectional views of the starboard wing
lift spars
and supporting rollers in fully extended (Figure 21), ina:rmediate (Figure
22), wad fully
3 0 retracted (Figure 23) cmtfiguratioos.
Figure 24 is a cross-sectiottai view of a wing extension panel talrta on the
line A-A in-
Figure 13.
Figure 25 shown a cross-sectional view of a wing taken on the line H-B in
Figure 13.
Figure 26 shows a cross-sectional view of a wing on the tine C-C in Figure 15.
CA 02374576 2002-03-14
77316-13D
-5-
Figure 27 is a perspective view of the supporting lift and drag spars of a
starboard wing
extension assembly according to the invention, showing the interlocking
relationship of lift a~
drag spare of~a pori wing extension assembly and also showing a preferred
cable menhanism
useful for extending and retracting the extendable wing sections. The arrows
indicate direction
of motion during wing rea~ion.
Figure 28 is an enlarged derail of encircled portion XXViZI of Figure 27.
Figure 29 is a perspecxive view of starboard wing support structures similar
to Figure
27, showing as alternuive screw-type mechanism for extending and retracting
the wing
extension panels.
Figures 30 and 31 are cross-sectional views of a wing takes on line J-J of
Figure I5.
showing a preferred mechanism for coordinsted acaration of the ailerons on the
feed wing
section and on the wing extension panel. The componems of Figures 30 and 31
are exactly cta:
same: the two figures show simultan~us adjustment of the positions of the
fixed wing aikmn
( 10) and the extension panel aileron ( 12) relative to the atuionary surfacx
of the wing (2) as the
ailerons are trimmed from a raised position (Figure 30) to a lowered position
(Figure 31).
Figure 32 shows the preferred design for acwuion of the ailerons using a cable
system
for the extension aikroas (12) and a~puah-pull rod system for the fixed wing
sxtioa flap (72)
. and aileron (10).
Figure 33 is a perspcaive diagrammatic view of an aliernace design for the
actuation of
2 0 the aileron systems of an aircraft acxording to the invention. In contrast
to the acarad~ system
depicted in Figure 30, this figure shows a cable system for xarating herb the
flaps (72) and
ailerons (10) of the fixed wing section and the ailerons (12) of the wing
extension assembly.
Figure 34 is a cross-rational view of the fuselage taken on line I-I in Figtue
15,
showing chc relative positions of the powerpiants and the beh drive systrm in
a preferred
embodiment of this invend~. Air cooled aircraft engines are depicted.
Figure 35 is a trees-sectional from elevation of as sinxaft acxording to the
invention
showing the paaitioniqg of the engines in the fuselage, the belt and pulley
system for driving the
propellers, and the pivotally mounted arntaatra providing pivoting mourns for
both the landing
gear and the propellers. The compo>Kms depicted in this figure ue shown in a
configuratiofl
3 0 typical of in-flight operation (cf. Figure 4), with landing gear rettatxed
into the fuselage.
Figure 36 is a schematic plan view looking down ~ a compound wing aweture
according to the invention and a prefi ~-red belt drive system for curnittg
pusher-type propellers
mounted in pivoting armature mounts according to the invention. The drawing
shows the
relative positions of the port wing extension panel (5) and the starboard wing
exteeuion parcel
3 5 (4) ituide the fixed wing section ( 1 ). Also visible in this schematic
view are strucattal
CA 02374576 2002-03-14
77316-13D
-6-
compone~ of tlx; wing extension panels, i.e., front (31) and rear (33) lift
spars of the port
wing extension assembly and port drag spar (35) (diagonal lines), as well as
the starboard front
(30) and rear (32) lift spars and drag spar (34) (cross-hatched) of the
starboard wing extension
assembly. The wing extension panels are shown partly extended, and the
inoerlocting
juxtaposition of the supporting spars (30, 31. 32, 33. 34, 3~ within the fated
wing structure (1)
is also shown. Also illustrated in Figure 36 is a preferred arrangement of
port (diagonal lines)
and starboard (cross-hatched) drive belts (84, 99) for actuating port and
starboard propellers (9
sad 8, respectively) via propeller drive shafts (81).
Figure 37 is a side elevation of the engines and drive belt system disclosed
herein,
showing details of the gear box (110) of Figure 34.
Figure 38 is a perspective view of starboard sad port curved mounaag armatures
and
mounted propellers, shown in isolation from the aircraft (cf. Figure 4) but in
proper relation to
each other. The armatures are shovm in the relative positioat they would have,
e.g.. in an
aircraft as depicted in Figure 4, wherein the propeller centers are in line
with the planes of nhe
wings and the landing gear are fully retraced imide the fuselage.
Figure 39 is a frontal diagram of two pivotal mounting armatures in the same
relation as
depicted in Figure 38, provided to indicate the preferred shape and dimeaaioos
of such
Figure 40 shows a cross-sectional view of a wing taken on the line D-D of
Figure 15.
2 0 Figure 41 is a perspective view of starboard and port curved mounting
armatures and
mounted propellers, shown in isolation from the airaaft (cf. Figure 8. Figure
5'n but in proper
relation to each other. The armatures are shown in their relative positions,
e.g., in an aircraft
as depicted in Figure 1, wherein the propellers are positioned above the
surface of wings and
caster-type wheel gear are deployed, as appropriate for a runway landing.
2 5 Figure 42 is a perspaxive view of starboard and port curved mounting
armatures and
mounted propellers, shown in isolation from the aircraft (cf. Figure 9) but in
proper relation to
tech other. The armature: are shown in their relative positions, e.g., is an
aircraft as depicted
in Figure 9, wherein the propellers are raised to their maximum distance above
the wings and
the pontoon gee are fully deployed. as apprvprim for a water landing.
3 0 Figure 43 is a cross-sectional view of a wing taken on the line E-E of
Figure 14,
showing the relative position of the propeller mounting to the wing when the
aircraft is in a
talceoffllanding configuration as depicted in Figures 1. 6, and 8. In a
cutaway, the relationship
between the propeller, propeller shaft and propeller drive belt is shown.
CA 02374576 2002-03-14
77316-13D
_7_
Figure 44 is a cross-saxional diagTammadc view of the forward fuselage of an
aircraft
of the invention, taken on line F-F in Figure 11, showing the structures of a
focwud landing
gear component of the compound landing gear in a fully retracted
configuration.
Figure 45 is a similar forwud cross-secdo~nal view to Figure 44, except that
the forwud
Landing gear are shown partially extended.
Figure 46 is a simile cross-sectional view to Figure 44, except the forwud
landing gee
are shown fully extended (uncompressed). in a configuration typical of the
instant before
landing or the instant after takeoff.
Figure 47 is a simile cross-sectional view to Figure 44, except the the
forward landing
gee are shown extended and fully compressed. in a configuration typical of a
high-impact
landing on a hud surface.
Figure 48 is a simile forward cross-sectional view to Figure 44, extxpt that
the forward
landing gee are shown fully extended to support the weight of the nose of the
aircraft and in a
configuration appropriate to taxiing.
Figure 49 is a simile cross-sectional view to Figure 44, except that the skis
of the
compound forwud landing gee ue shown fully extended, in a configuration
appropriate to
landing on a snowy or icy surface.
Figure 50 is a cross-sectional diagrammatic view of the cena~al portion of the
fuselage of
an aircraft according to the invention, taken ~ line F-F of Figure 11. The
outer fuselage panels
2 0 that enclose the main central landing gear component of a compound landing
gee are shown in
the proper in-flight position, forming an aerodynamically smooth outer
surface.
Figure 51 is a cross-sectional view simile to Figure 50, except the outer
fuselage panels
are shown by phantom lines in order to expose the struc:itra of the main
central landing gee.
The componems of a preFerred main central landing gee according to the
invention are shown.
2 5 fully folded and enclosed within the fuselage, i.e., in their fully
raratxed and stowed position
appropriate during flight. The relative positions of the inboard engines
(shorvn in silhouette)
and beh drive mechanisms, landing gear, primary fuselage structure, wing
structure. attd wing
extension assemblies are shown in this figure.
Figure 52 is a perspective elevation of a preferred main cena~a! landing gear
assembly,
3 0 shown in a fully revaeued configuration, as the asxmbly wou~ be positioned
in flight. In such
configuration, the lower surface of the skis would form part of the aura
surface of the aircraft's
fuselage; the rest of the landing gee assembly would be inside the fuselage of
the aircraft, out
of the airstream.
Figure 53 is a perspative elevation of a preferred main central landing gear
component
3 5 of the compound landing gee of the invention. The assembly shown unifies
central wheel-typr
CA 02374576 2002-03-14
77316-13D
$_
landing gear (not visible in this view), ski-type landing gear a~ flotation-
assisting hollow
design ski snots. The assembly is shown in a deployed configuration that
places tlu wheel-type
landing gear in a vertical position suitable for use in landing on a hard
surfacx or runway. (Cf.
Figure 54.) In this position tl~ skis are semi-deployed and will not meet the
surface during a
normallaoding.
Figure 54 is a cross-scaional view of the midsection of the fuselage of an
aircraft
according to the invention, taken on line P-P of Figure 7 and depicting the
compound landing
gear depioyod so as to make use of the wheelod gear, i.e., in the
configuration most suitable for
Landing on, taking off from, and taxiing on a hard surface.
Figure 55 is a cross-sectional view of the midsection of the fuselage of an
aircraft
according to the invention, illustrating compound landing gear deployed so as
to make use of
the main ski loading gear, i.e., in the configuration most suitable for
landing on, tasting off
from. and taxiing on a snow-covered surface.
Figure 56 is a cross-sectional front elevation of the midsection of the
aircraft as
illustracsd in Figure 54, showing strucarres of the main oemral and
stabilizing landing gear
components in the configuration appropriate to takeoff and landing or taxiing
on hard surface
runways. (Cf. Figure 7.) Several strucatral elemea~ not related to the ia~ing
gear are omitted
. . . from this view.
Figure 57 is a crass-satiooal fret elevation of the midaecaoa of the aircraft
simile to
the configuration depicxed in Figure 56, except that the deployment of the
landing gear has been
modified as appropriate for takeoff sad larding on intermittent snow over a
hard surfacx
runway. Several suvctural elemema not related to lading gear are omitted from
this view.
Figure 58 is a cross-axaonal front elevation of the midsecrion of the aircraft
as
illustrated in Figure 56. showing swctures of the main centre! landing gear
and stabilizing
2 S landing gear compouencs in the configuration appropriate for takeoff and
loading on snow. (Cf.
Figure 8.) Several st:ucwral ekanena not related to landing gear are omimed
from thin view.
Figure 59 is a doss-sectional front elevation of the midsection of the
aircraft similar to
the configuration depicted in Figure 56, with main ~aral landing gear rara~ed,
showing the
mvuruiag armatures (6 std 'n, and thus the pontoon subcompooems (22 and 23)
fully deployed.
3 0 i.e., in the configuration appropriate to takeoff and landing oo water.
(Cf. Figure 9.) Several
swcarral elements rrot related to landing gear are omitted from this view.
Figures 60 and 61 show schematic illustrations of steering mechanisms for
aircraft of
this invemion. Figure 60 shows a preferred staring control system, in which
control of the
trout and rear wheels are linked such that turning the rear (main) gear
simultaaeousiy turns the
3 5 nose landing gear.
CA 02374576 2002-03-14
77316-13D
_g.
Figure 61 illusu~ates a similar steering control system in which the nose gad
main geu
are controlled tadependetlttly.
Figure 62 is an eapioded perspective view of an aircraft according to the
invention
showing the modulu components of t~ fuselage and major components of the
aircraft.
Alternative wide-fuselage cugo-type components (231 and 232) to the standard
passenger-type
upper fuselage componems (3 and 2) are also shown.
Figure 63 shows a plan view of a wide-fuselage embodiment of the invention.
This
fuselage option can be compared to the standard fuselage configuration shown
in Figure 15.
Best ode for Curving Out the lm~ention
Preferred embodiments of the present invention will be described below with
reference
to the drawings. It will be immediately appraiated, however, that the design
features described
may be altered or modified for parriculu purposes gad that the production of
many alternative
embodiments of the aircraft described herein will be possible in view of this
dixlosure. A11
such alterations. modifications and additional embodiments are contemplated
herein and ue
intended to fall within the scope of this description and the appended claims.
The following
description is not intended to limit the scope of the invention in any way.
Preferred embodiments of a complete aircraft according to the present
invention ue
shown-in various configuruioas and views in Figures 1, 2, 3. 4, 5. 6, 8, 9,
10, 11, 12. 13, 14,
15 and 62. The preferred features of the aircraft include compound wings
comprising a fined
2 0 wing section also housing port and stuboud ext~endabk wing panels, which
can be deployed
(in-flight, if desired) to increase wing surface area and lift; pivoting
mounting armatures that
serve as propeller mounts and also as aft loading geu mrnuaa, the armatures
serving to change
simultaneously the position of the propellers and the compound landing geu
with respecx to the
rest of the aircraft, i.e., placing the propellers in the optimal position for
landing on or caring
2 5 off from a variety of surfaces or for cruising flight, such positioning of
the propellers occurring
auwmaticaiiy as c~pound landing geu mounted on the armuurcs are rotated to
expose the
appropriate type of landing geu (wheeled geu, sris, pontooaa) for different
loading surfaces
(tu~c. scow. water) or are rotated to nest is recesses in the fuselage of the
aircraft during
flight; modulu fuselage design permitting augmentation of the aircraft in
production to meet
3 0 different pasxager~arryit~ or cu8o.carrying txeds without re-design;
elimination of an aft
fuselage saxion and a stronger, more cosily fabricated tail satioa; gad a
power train featuring
inboard engine mounting (preferably twin, taademly mounted and opposed
engines) gad a novel
belt drive for propellers.
Referring to Figure 1, an aircraft according to the invention cad featuring
several design
3 5 innovations is illustrated. The overall configuration of this embodimetu
is of a cantilever high-
CA 02374576 2002-03-14
77316-13D
-10-
wing, amphibious monoplane, preferably having a hull-bosomed fuselage and twin
rear-facing,
pusher-type Propellers.
Tlu; wings are compound in structure, comprising a main wing section (1) fixed
to the
main fuselage structure (300), port and starboard leading edge slats ( 15 and
14, rapatively),
and port and starboard main ailerons (11 and 10, respectively). The main
fuselage section
includes an aft tail section (310), shown in Figure t a a cantilever T tail,
with steering surfxes
including a rudder (311) and an elevator (312). The primary aikroos 10 and 11
of the fixed
main wing section ( 1 ) are aerodynamically shaped surfaces on the trailing
edges of the wing
section and are used for control of the aircraft motion around the
longitudinal axis (roll control),
primarily at high speeds. The main wing section (1) also houses two
telescoping extendable
wing sections (4 and 5), which can be extended (picaued) or fully retracted
within the main
wing section (1), as illustrated in Figures 4. 11 and 20. The extendable wing
sections (port. 5;
starboard, 4) also have leading edge slats (port, 17; starboard, 16) and
aikrona (poet, 13; .~
starboard. 12), as on the main wing section (1). The leading edge slats (14
acid IS) of the fixed
wing saxion ( 1 ) are (preferably) focwardiy extendable to change the lift
characteristics of the
compound wing, and the ailerons (10-13) are trimmed to steer the aircraft in
flight. Preferably
the port main wing aileron (11) and the port exteruion panel aileron (13) are
actuated by the
same or connxced mechanisms, and the starboard main wing saxion aileron ( 10)
and the
starboard extension panel aileron (12) are similarly co-xwated, so that the
movements of both
sets of ailerons are complaely coordinated and may be effaood without using
multiple controls.
Likewise, it is preferred that the leading edge slats ( 14 and 15) ate co-
acasated, so that their
operation is coordinated and requires manipulation of a minimum mamba of
com~rola.
In most preferred embodiments, the compound main wing setxion (I) futtha
includes
rep for acxxpting pivoting propeller mounts (6, ~, which may be rotated to
raise the
.,
2 5 propelkra above the level of the wing (preferable f~ water landings) or to
nest the propeller
mourns in recesses in the wing (see. Figures 3-5) to bring the propellers eves
with the wing
surface (ptrfaabk for climbout and cruising flight).
The compound wing structure described herein lends aevua! advann~a to an
aircraft.
When the extendable wing panels (4, 5) are fully retracted and thus completely
housed within
3 0 the fixed main wing section ( 1 ), out of the airstream, the wing span of
the aircraft is
considerably shortened (e.g., reduced almost 50°J6), giving the
aircraft inerebed
maneuverability and higher cross-wind stability. The ability to retract the
wing panels (4, 5)
and thereby significantly reduce the wing span leads to improved safety
chara~cxeristics for the
aircraft in that the wing bending stresses in the cruise and maneuvering
configurations (see.
35 Figures 4 and 5) are reduced. Wing stresses are also reduced by the
interlocking juxtapositiun
CA 02374576 2002-03-14
77316-13D
-11-
of the supporting spars (discussed. ice; ref. Figure 36) of the eauadabk wing
sections. when
the wing seaiona are fully raracted. The interlocking support spar design also
makes it
posaibk to increase the wing span up to 90-9596 while maintaining the
stru~ural integrity a~
operability of the wing, a capability that was not attainable with previous
designs.
The ability to extend the extendable wing sections (4, 5) while in flight
makes aircraft
according to the present invention ideal for pilot training by providing the
capability of
simulating t~ flying characteristics of a wide variety of aircraft. When the
extension panels are
reaacted, the aircraft has spend, maneuverability and wing stress-beuing
characteristics similar
to xrobatic or military combat aircraft; when the wing extension panels are
fully extended. the
aircraft simulates the lower stall speed, greater lift and high altitude
flying characterisdes of
STOL, commuter and patrol aircraft; and with intertxdiate, variable extension
of the
telescoping wing extension panels, flight characteristics can be varied to
match those of other
types of aircraft or to tailor the aircraft's properties in-flight to meet
changing air and wind
conditions, or to prepare for landing on or takeoff from a variay of diffecenc
surfaces.
The retractable wing section feature also make the aircraft of this design
suitable for
full-scale aerodynamic testing of new airfoil sbapa in-flight. For example,
new airfoil designs
may be fitted to the aircraft as extendable wing seaiona (4, ~. gradually and
safely extended
while the aircraft is in flight, and rearacted out of the airstream if
undesirable characteristics are
decaxcd.
2 0 Additional advacuages provided by the telescoping wing feadtra include
improved
safety in cond'ttioas of ice accumulation on the wings by virwe of the ability
to retract a major
portion of the wing during ice accumulation and extend said wing sections
(free of ice) during
landing. The aircraft tray also convert from a relatively long wing span that
is advantageous
for takeoff and loading, fuel efficient long range flight, and high altitude
flight to a shorter wing
2 S span that is effici~t for high speed flight and advatuageous for storage
and operation around .
obxaclea (such as other aircraft) on the ground or in underdeck stooge on a
ship. This wing
design also providd high wing loading (weight per wing area) during cruise
(retracted wing
paoela). which gives pilot and passengers a relatively smooth ride through
turbulent air. and a
low wing loading (euaded wing panels) during takeoff and landing to provide an
improved
3 0 operational safety margin at low airspeeds (greater lift, lower stall
speeds) and lower landing
speeds, resuhing in a reduced potential for damage or injury in landing
axide~. This wing
design also provides a meam of expanding wing surface area for carrying larger
payloads or a
larger quantity of fuel for long trips, or a means of reducing wing surface
area for more
efficient cruising flight with minimum payloads or low fuel.
CA 02374576 2002-03-14
77316-13D
-12-
Referring again to Figure 1, the fixod main wing section ( 1) and an optional
fuselage
extension module and cabin extension assembly (2) are fixedly attached to tlk
main fuselage
section (300). -An upper cockpit assembly (3), attached to a forward cabin
module (233 in
Figure 62) that houses the forward landing gear (e.g., 21 and 29), is attached
et~-to-end to an
upper cabin extension assembly (2) and a cabin extension module (234 in Figure
62), to provide
a continuous enclosed cockpit and cabin area forward of the main fuselage
sxtion (300).
Alternatively, as picdued in Figure 5, the forward cabin module and the upper
cocrpit assembly
(3) may be attached end-to-end to the main fuselage section (300), e.g., where
no additional
cabin/cargo spact or a smaller, lighter weight aircraft is desired. The nose
assembly (3), any
fuselage extensions (2), and the male fuselage saxion (300) toget~r comprise
the fuselage and
tail of the aircraft as a whole.
The front landing gear are comprised of elements such as the front wheel (21)
aztd the
froze sitis (29) and may be mounted in and attached to the forward section of
tlx fuselage
through support and exteosionlretraction members explained in more detail
jpøg.
The wing extension panels (4 and 5) are mouztted inside the fixed wing ration
(1) so as
to be simultanea~usly exteztdable laterally out from the starboard and port
wing tips (38 and 39,
respectively) or simultaneously retractable into the fixed wing sectia~n (1).
When fully tetraaad.
. . the extension panels (4 and 5) are completely enclosed within the fixed
wing section ( 1 ) of the
aircraft. and the exteztsion panel wing tips (36 and 37) meet azid preferably
nest into the fixod
wing tips (38 and 39) to form an aerodynamic teardrop wing tip. (See, e.g.,
Figures 4 and 7.)
The embodimetu of Figure 1 also shows curved mounting armatures (6 and 7)
which are
pivotally attached to the rear of the fixed wing section (1), near the
fuselage. The armatures (6
attd 7) not only provide a mount for the pz~opelleza (8 and 9) but also
provide a mount for rear
stabilizer landing wheels (19 and 20) and flotatiozzal poe><oon assemblies (22
(not visible in this
Z5 figure) std 23), which serve as outrigger-like stabilizers during
amphibious operations. The
mourning armatures (6 and 7) are generally pan-shaped when viewed edge-on
(see. e.g.. Figure
5 and other front elevation), and the curvature of the umaarres permits the
pilot to bring the
wheeled landing gear ( 19 and 20) or aleernatively the pontoon landing gear
(22 and 23) into
position for use by causing the arznaturea to rotate about their pivotal
attachment. Additionally.
3 0 because the armadtra (6 and 7) also serve as a mount for the propellers (8
sad 9), raacing the
desired landing gear (wheels or pontoons) into position for use simultaneously
will change the
posidozts of the propellers relative to the wing and fuselage. The armatures
are shaped so that
at the maximum rotation of the lower end of each armswre away from the
fuselage of the
aircraft. that is, to expose the pontoon landing gear (22 and 23). the
propellers simultaneously
3 5 are rotated away from and above the wing, toward the centerline of the
aircraft, so that the
CA 02374576 2002-03-14
7?316-13D
-13-
propellers are raised to a maximum height above the water and are shielded
fmot water spray by
the wingi nerd fuselage. (See, Figure 9.)
The mounting armatures (6 and ?) are preferably designed so that the entire
propelkr
can be raised above the surface of the wing when a water landing is auempted.
Water spray
damages propelkrs: water droplets can cause pitting of the propeller blades,
the tips of which
are moving at near-sonic speeds. In conventional amphibious aircraft designs,
at least the lower
arc of the propeller is often exposed to water spray, but in preferred
embodiments of this
invention, the mounting armawres will cause the entire arc of the propeller to
be shielded from
water spray by the wiagi, when the propelkcs are positioned for a water
landing. For hard
surface landings. also, the armatures (6 sad ~ will position the propellers
above the wing,
where the propellers are much less likely to contact objects oa the ground or.
to come into
contxt with people moving around the aircraft.
In the most preferred embodiments, the armarures (6 sad ?) are additionally
shaped to
nest in recesses of the wings directly above the flaps (72. actually split
flaps, only a fracdoa of
the thickness of the wing) and on either side of tlae fuselage (305), when the
armatures are
pivoted to align the propellers with the surface of the wing and to r~ra~x the
landing gear. This
means that below the pivot point, the ~outtr surfaces of the armatures (6 and
T) when fully
rotated will become flush with the surface of the main fuxlage section (300):
sad above the
pivot point, the outer surface of the armatures (6 and ?) when fully rotated
will be flush with
2 0 and biome part of the aerodynamic surface of the fixed wing section ( 1 ).
.
Recognising that many modifications sad alternative choices of design or
materials are
possible from the deseripti~ herein, a moat preferred embodiment contemplated
f~ the present
invention will have the genersl coafiguratioa depicted in Figure 1 with the
following
dimensions:
2 5 center (fixed) wing aectioo ( 1 is Fig. 1 ): NACA 66~-018 at root acrd
tip, dihedral 3
degrees, swap -3.28 degrees (forward) at the a chord, with two imeraally
mouatad
telescoping wing exteaaioa panels, 0 degrees swap;
wing span (panels fully retracted): 26 feet (7.92 meters):
wing span (paneia fully extended): 50 fen ( 15.24 meters. 92.31 ~6 increase
over fully
3 0 rara~d):
wing chord at feed root: 10 fen. 8 i>xbes (3.25 meters):
wing chord at feed tip: 6 fat. 8 inches (2.03 niters);
wing chord at extension root: 3 feet. 8 inches ( 1.12 meters):
wing chord a excetuion tip: 3 feet. 8 iacdes ( 1.12 meters):
3 5 wing aspax rule (reaaaed) 3.125:
CA 02374576 2002-03-14
77316-13D
-14-
wing aspect ratio (extended) 8.33;
moveable leading edge slats on center wing suction, fixed leading edge slur on
extension sections;
construction: ail wing sections preferably constructed of flush riveted
aluminum;
cantilever T-type tail constructed of flush riveted aluminum, having a
horizontal
stabilizer and an elevator (optionally including servo-tabs);
tailplane span: 14 feet, 7 inches (4.44 meters);
lower fuselage: riveted aluminum for amphibious hull and main fuselage section
(300 in
Fig. 1);
upper fuselage (cabin): fiberglass composite;
fuselage construction: 3 sections (nose, center cabin, and main fuselage
(engine
enclosure) including tail section) bolted end-to-end;
overall length: 40 feet ( 12.19 meters);
overall height: 12 feet. 4 inches (3.75 meters);
wheelbase: 20 feet. 10 inches (6.35 ratters);
wheel trxk: 10 feet. 6 inches (3.2 meters);
propeller diameter: 6 feet. 6 inches (1.98 ).
Of course, the foregoing dimensions and preferred materials may be modified
without
departing from the concept of this invention, so long as the inventive
fesntra, as recited in the
claims, are incorporated.
Referring to Figure 2, an aircraft of the same general configuration as
iliustratsd in
Figure 1 is shown, except that an alternative tail section in the shape of an
imrerted "T" is
shown, equipped with a rudder (311) and a single elevator plane (312). All
other features of
this aircraft are as diaruased above for Figure 1. Mast prefetnd embodies of
the invention
2 5 will have the T tail comiguration of Figure 1, wherein the tail surfaces
are in the direct prop
wash when the propelleta are raised above the wing and are out of the prop
wash wheo the
propellers are lowered to be level with the wing. This design lends
maneuverability to the
aircraft at lauding and takeoff speeds. when maneuverability is most critical.
Including various of the lnYenLlYe features of this invemion into as airecaft
design
3 0 permits incorporation of a unique tail configuration, which is apparem is
the embodiments of
Figures 1 and 2. Inboard mounting of the engines is the aft portion of the
fuselage, under and
just aft of the wings (ref. Figure 51) makes the inciusioo of an fuselage
section aft of the wings
undesirable and impractical: therefore. the fuselage can advantageously begin
to taper
immediately aft of the wings to form a vertical tail section as shown. The
tail ration can taper
3 5 in a straight line from the end of the fuselage, in contrast to
conventional deigns including an
CA 02374576 2002-03-14
77316-13D
-15-
aft fuselage, which leads to structural advantages in that stiffening
stringers and such members
are not bent or-made to follow contours and are thus able to withstand greater
stresses. The
horizontal stabilizer'piane and elevator of the tail arc supported by a much
stronger and stifFer
tail structure, and thus undesirable flutter of the tail control surfaces is
eliminated. The
S illustrated vercicat tail (Figure 1) is highly swept aft to balance
aerodynamic forces, to reduce
drag, to clear the propeller arcs at all propeller positions, etc., which
leads to a tail section
having a longer chord than normal. This also provides a very long vertical
steering surface
(rudder), which is believed to be unique to the present design. Modeling
studies (discussed
of the aircraft have indicated that the unusual span of the rudder does not
dtaract from the
performance of the aircraft or lead to undesirabk flying characxeristics.
Referring to Figure 3, the aircraft of Figure 1 is depicted in flight, with
the wing
extension panels (4 and 5) fully extended. The arc of the propellers (8 and 9
in Figure 1) is
depieued by circles (labeled 8 and 9 here). The forward landing gear (i.e., 21
and 29 in Figure
1 ) are not visible in this figure, having been fully retracted into the nose
section. Similarly, the
curved mounting armatures (6 and 7) are picaued here pivoted to a position
such that the rear
landing gear (i.e., 19. 20 and 23 in Figure 1) are retracted and >toused
within the fuselage
section (300) under the wing, and the lower portion of the port armature (7)
is sees to nest in
the fuselage, flush with the outer surface of the main fuselage secxioo (300).
The upper portions
of both curved mo<tnting armatures (6 and 7) are pictured here pivoted to a
position such that
2 0 the mounted propellers (8 and 9) are a the level of the wing, and the
armatures (6 and 7) are
nesting in wing recesses such that the outer surfaces of the armatures (6 and
7) form flush,
continuous surfaces with the surface of the main wing section (1). All other
aspects of this
figure are as depicted in Figure 1.
Referring to Figure 4, the aircraft of Figutts 1 and 2 is shown in flight,
with the wing
2 5 extension panels (4 and 3 in Figure 1 ) fully retracted and housed within
the main wing secti~
(1). In this configuration and in this port side perspective view, the only
part of either wing
cxteasi~ panel visible is the port wing extension panel tip (37). seen here
mated with the port
fixed wing tip (39) to form an aerodynamic teardrop wing tip. All other
aspects of this figure
are as depicted in Figure 3.
3 0 Referring to Figure 5, an aircraft substantially identical to the aircraft
of Figures 1 and
4 is shown in flight, with the wing extension panels (4 and 5 in Figure I)
fully raracoed and
housed within the main wing section (1). In this configuration, the cabin
extension module and
upper cabin extetuion assembly (2) shown in previous figurrs have bees
removed, resulting in a
shorter fuselage and a decrease in overall aircraft weight. In embodiments of
this invention
3 5 where (as here) the engines are mounted inboard, on the centerline of the
aircraft and under the
CA 02374576 2002-03-14
77316-13D
-16-
wings, modification of the fuselage in the manner illustrated t.aa be
accommodated in the
tttaaufacatring atep~ ~y. simply substituting lighter engines to redistribute
the weight of the
aircraft. No general redesign of the aircraft is naessary, and oo retooling of
t>u manufacturing
process must be done. As in Figure 4, the only part of either wing extension
panel visible is the
port wing extension panel tip (37), seen here mated with the port fixed wing
tip (39) to form an
aerodynamic teardrop wing tip. All other aspects of this figure are as
depicted in Figure 4.
Referring to Figures 6 and 7, an aircraft axording to the invention is shown
is fr~tal
elevation, viewed none-on. The aircraft incorporates the compound wing
assembly diacxtssed
~y~, comprising main wing struccure (1) and ulescoping extendable wing xctions
(4 and 5).
As picaued, the fixed wing xcxioo ( 1 ) also comprises leading edge slats ( 14
and 15) and
teardrop or bullet-shaped wing tips (38 and 39). The wing extension panels (4
and 5) are alto
picatrcd with leading odge slats ( 16 and 17) and wing tip caps (36 and 37),
which mate with the
feed wing tips (38 and 39) to form aerodynamic teardrop wing tips, when the
wing extension
panels (4 and 5) are fully retracted within the fixed wing section (see. Fig.
7). Ailerons (10,
11) and flips (72) are also s6avn.
The aircraft illustrated in Figut~es 6 and 7 also incorporates curved mourning
armatut~es
(6 and 7), pivotally attached to the roots of the wings. each atmturtre
comprising an upper std
' ' and a Tower end with raped to the pivotal attachment, the upper end of
each armature being
equipped and configured to accept a propeller asxmbly or to act as a propeller
mount, and the
2 0 louver end of each armature being equipped and configured to acxxpt or to
as as a mourn for a
compound landing gear comprising stabilizing whxls (18 and 19) and pontoon
members (22 and
23). Propeller: (8 and 9) are shown mounted on the upper ends of the arm~wres
(6 and 7).
The position of the ends of the mounting armatures in relation to the fuselage
of the aircraft
(i.e., the degrx of rotaries about the pivotal attxhment) is preferably
cotnrolled by mesas of
2 5 multilitat acting struts (280 and 281 ). Extension of the struts (280 sad
281 ) pivots the
armaarres so that the upper end of each armature (6 and 7) and thus the
propeller mounts are
rotated upward from the level of the wing sad iawud toward the c~etline of the
fuselage:
extetuioo of the struts (280 and 281) simultaneously pivots the armatura so
that the lower end
of each armature (6 and 7) and thus the compound landing gear ( 18, 19, 22,
23) art rotated
3 0 outward from the fuselage. At an intermediate point of extsosion (shown)
of the acataciug struts
(280 and 281). the armatures are in a position wherein the stabilizing tzar
landing wheels (18
and 19) are swung into the proper orientation to assist in supporting the
aircraft during a hard-
surface landing. At full extension (not shown here) of the actuating struts
(280 and 281), the
armacura (6 and 7) are rotated to a position where the upper cads of the
armatures and the
3 5 propeller mounts ate at a maximum distance above the wing structure ( 1 )
sad the pontoon
CA 02374576 2002-03-14
77316-13D
_17_
members (22 and 23) of the compound landing gear arc in the proper orientation
to assist in
supporting the-aircraft during an amphibious landing. The armatures (6 and 7)
are preferably
shaped so that when the actuating struts (280 and 281) are fully retracted,
the upper ends of the
arrmantra (ti and 7) nest in recesses (not shown) in the feed wing section
(1), with ono surfatx
of each armature becoming flush with the aerodynamic surface of the wing and
forming part of
the airfoil, and the lower ends of the armatures (ti and 7) nest in recesses
(not shown) of the
fuselage, with dx outer surface of lower end of each artnantre becoming flush
with the surface
of the fuselage.
Forward landing gear are also illustrated in Figures 6 and 7 sad arc also
compound,
comprising a steaable forward landing wheel (21) and forward sitis (29). The
forward landing
gear (21, 29) arc fully rerractabie within the nose section of the fuselage,
and preferably the
lower surfaces of the skis (29), wbea retracted, form pact of the surface of
the fuselage and thus
do not create any external drag during flight. Steerable rear landing wheels
(20) are also .
depiaod in Figures 6 and 7, however they arc partially hidden in this view by
the forward
landing w6cel (21). (See, Figures 56 and 58, item 20.)
Referring to Figures 8, 9 and 10, as aircraft similar to that depicted in
Figure 6 is
shown, except that in these figures positioning of the compound landing gear
in orientations
. . . appropriate for snow landing/takeoff (Figure 8), wiser landing/ takeoff
(Figure 9), and slow
taxiing in water (Figure 10), respectively, are illustrated.
2 0 In Figure 8, a frontal virw is shown of the forward skis (29) and the reu
skis ( 114),
deployed to a position where they are acting as the primary landing gear for
the aircraft. All
other aspcas of Figure 8 are as illustrated in Figure 6.
In Figure 9, a frontal view is shown of the pontoon members (22, 23), rotated
into
proper position to act as stabilizing outriggers during a wiser landing. This
positioning of the
2 5 outrigger poatoom (22, 23) is effected by full extension of the multilinic
actuating struts (280,
281). Note that full extension of the multilink actuating struts (280. 281)
causes the stabilizing
rear landing wbeeb ( 18. 19) to be rea~acted into recesses in the lower end of
the armatures (6
and '~. The primary larding geu for the aircraft in such an operation is the
hull-tike fuselage.
the forwardmoat section of which is visible in this frontal elevation. The
hull fuselage of the
30 embodimeaot of Figure 9 has a pronounced 'V" shape in cross-section (high
deadrise aagk). In
contrast to shallower bull designs, the V-shaped hull improves baadliag of the
aircraft in choppy
wiser and lowers the G load on the hull during water landings. All other
aspaxs of Figure 9
are as illustrated in Figure 6.
Figure 10 presents the same view of the aircraft as in Figure 9, except that
the auto-
3 5 retracting rear stabilizing wheels ( 18. 19) have been partially lowered
and the lovuer cads of thr
CA 02374576 2002-03-14
77316-13D
18-
armatures (6, 7) have been rotated slightly downward and inward by
articulation of the
innermost link of each of the multilink actuating struts (280. 281).
Ftotuional elements ( 18, 19.
22, 23) have thus been forcxd downward against the surface of the water,
thereby leveling the
aircraft and improving the taxiing performaacx of the aircraft at slow speeds
on water. All
other aspects of this figure are the same as in Figure 6.
Referring to Figures 11 and 12, an aircraft according to the invention and as
depicted in
Figures 6 and 7 is shown in frontal elevation, with the extendabk wing panels
(4 and 5 in
Figure 12) fully retracted in Figure 11, so that the wing tip caps (36 and 37)
are mated with the
feed wing tips (38 and 39) to form aerodynamic teardrop wing tips, and with
the extendable
wing panels fully extended in Figure 12. The main wing structure (1), the
leading edge slats
( 14, 15, 16 and 17), the forward section with upper cockpit assembly (3), and
the propellers (8
and 9) all are as depicted in Figures 6 and 7.
The forward skis (29) are illustrated in Figure 11 in their fully reQa~d
positi~,
wherein the lower surface of the skis is flush with the fuselage surface. It
is an espxially
preferred aspect of aircraft according to this invention that all landing gear
may be fully
retracted within the fuselage, out of the airstream, and that landing gear
doors (and their
associated mechanisms) may be eliminated. since the slti ekm~s are preferably
designed to
. . ~g~ ~"~, ~ ~1~. The landing gear designs disclosed herein are believed to
be the first
designs that combine full reu~accability of all landing gear eleaneats
(wheels, skis sad pontoons)
2 0 and elimination of gear-enclosing doors from the fuselage.
Referring to Figures 13, 14 and 15, the principal aspects of the cmopound wing
structure of the present invention are shown in plan. All elements depicted in
Figures 13. 14
and 15 are as described in Figures 4, 1 and 3, respectively. (See, also,
Figures 12. 6 and 11. )
2 5 Ooe of the principal inventive fucurss of this inrenaon is a compatnd
wing. Aircraft
incorpcxating this feature have the capability of being strucaually modified,
in flight, at the
option of the pilot, so as to exhibit a wide range of flight c6araaeriatus m
to adopt to a wide
variety of flight condition. In other words. aircraft incocporadag the
compound wing can be
made to behave, aerodynamically, like several diffcreot types of aircraft, by
the extension or
3 0 retraction of extendabk wing panels laterally from a central fixed wing
sear, as discussed
~. Aircraft of impr~ed performance, versatility and safety ate the result.
The compound wing feature and possible mechanisms for its operation are
illustrated in
Figures 16 through 33.
Figure 16 shows the coastructton of a stuboard wing eitteasion panel (4).
Previously
3 5 discussed external features such as the teardrop wing tip cap (36), the
leading edge slat ( 16) and
CA 02374576 2002-03-14
77316-13D
-19-
the ailtton (12) are shown. In this figure, the outer skin (26, e.g., of flush
riveud aluminum)
of the panel (4) is shown cut away to reveal internal support structures, such
as structural ribs
(27), reinforcing stringers ~(28), a forward lift spar (30), and a rear m aft
lift spar (32). All
such swcaues are typically consaucted of aluminum, fastened together by
rivettting. The wing
extension panel (4) also features a drag spar (34) positioned between the two
lift spars (30 and
32). All of the spars (30, 32, 34) extend the entire length of the extension
panel and roughly ao
equal length from the root .of the wing extension pail (4), A guide bar ( 116)
attached to the
drag spar (34) provides a racaas for guiding the extensionlrra~action movement
of the extension
panel (4) relative to the feed sxtion of the wing (not shown).
Figure 17 shows a more detailed view of the encircled portion XVII of Figure
16. Lift
and drag spars 30, 32 and 34 are seen to have an "I'-beam shape, characterized
by flange (79)
and web (80) portions. At the end of the lift spars (30 and 32), beam end
guide blocks (1177
are attached (e.g., riveted) into the arcs between the flanges (79) on one
side of each spar (the
forward side, in this figure); similarly, on the drag spar (34), a beam end
guide block (118) is
attached (e.g., riveted) in the area bc:wecn the flanges (79) on one side of
the drag spat (34)
(here, the upper side), Pairs of guide rollers (11~ are rotatably attac6a! to
each of the beam
end guide blocks (11?, 118). The lift spar guide rollers (11'n are positioned
ao as to provide a
rolls guide that will be in communication with the inside of lift spar flanges
of a port wing
e~etension panel. Similarly, the guide rollers (115) fated to the drag spar
beam end guide block
2 0 ( 118) are positioned to accept and provide a rolling guide fa a guide bar
fastened onto the drag
spar of a port wing extension panel assembly (not shown), which port extension
panel guide bar
would correspond to the picnued starboard drag spar guide bar (116). The drag
spar guide bar
( 116) is positioned to be aaxpted by a beam end guide roller system on a port
wing extension
assembly. This sysum of guide rollers and barn maintainer the proper
interlocking alignment of
2 5 the support spars of poet and starboard wing extea~ioo assemblies.
Preferably. the drag spar
guide bar (11~ sad its associated roller guides will have an interlocking
tongue-std-groove
shape, which will radttcs any vibration. Although the system of roller guides
and bars just
descn'bed is nor critical to the compound wing (i.e.. the port sad starboard
wing extension
panels' spars may simply be in slidable interlocking contact), the described
system of guides (or
3 0 its equivalent) will ensure smooth operation of the moveable panels of the
compound wing, will
decrease vibration of the spars, and will minimize the possibiftty of the
panels jamming is
flight.
Whereas Figures 16 and 17 illustrau the relative positions of the two wing
extension
panels (4 and 5 in Fig. 1) of the compound wing, Figures 18 and 20 show the
position of the
35 starboard wing extension panel (4) relative to the fixed wing section (l,
in phantom lines), and
CA 02374576 2002-03-14
77316-13D
-20~
show a preferred system of guide rollers for maintaining the position of the
extension panels
relative to the csmiat-fixed wing section. Referring to Figure 18, a starboard
wing extension
panel (4), with wing tip (36), leading edge slat ( 16), trailing edge aileron
( 12), and supporting
spars (30, 32, 34), is shown in simile aspect to that of Figure 16. In phamom
(dotted) lines.
approximately half of the fixed wing section (1) of the compound wing is
shown, extending
from fixed wing tip 38 to the centerline C (dished tine), denoting t~ central
plane of the
aircraft to which the wing section ( 1 ) is attached. The portion of the fixed
wing section ( 1 )
shown here includes an aileron (14) and a flap (72). As shown in this
illustration, the starboard
wing extension panel (4) is in sliding communication with the fixed wing
section (1): The
extension panel (4) is picaued a full extension from tlx distal. end of the
fixed wing ration (1).
and the entire assembly (e.g.. 4, 12, 16, 30, 32, 34, 36) is capable of
sliding as a unit inward
toward the root of the fixed wing (i.e., toward centerline C). A plurality of
extension panel
positioning rollers (40, 42. 44, 46, 48, 50). which are fastened to the inside
of the fixed wing
section (1) at the distal end, is positioned in relation to the wing extension
panel (4) to snugly
hold the extenaioa panel (4) while permitting (by rolling) extension and
retraction of the panel
(4) along the loaginrdinal axis of the wing section (1). Additional guide
rollers (52 and 54) may
be provided in association with some alternative mechanisms for co-acatation
of the extension
pane! ailerons and the fixed wing section ailerons. (See, Figure 30.) In
embodime~ using
cable or rod co-acatsaon mechanisms, such additional guide rollers (52 and 54)
may be
2 0 eliminated. (See, Figures 33 and 32.)
A further plurality of supporting spar positioning rollers (unnumbered. within
encircled
area 7QJ~ sxures and positions the wing extension assembly along tl>e
txttterline (C), where the
starboard support spars (30, 32, 34) mesh with the series of support spars
(3l. 33. 35) of the
port wing eximaioo assembly of the compound wing.
Referring to Figure 19, which is a more detailed view of encircled portion XIX
of
Figure 18, the mahia~g juxtaposition of the port (31, 33, 35) and starboard
(30, 32, 34)
supporting spas of the port and starboard wing extension assemblies is
illustrated. (Elemetas
such as guide rollers and end guide blocks (i.e., items 115-118 in Figure 17)
have bees omitted
here for clarity.) Each spar is secured and guided by a pair of rollers, which
are attached to the
3 0 feed wing structure (not shown):
SPAR ROLLERS
port lift spar 31 57 and 61
starboard lift spar 30 56 and 60
port drag spar 35 65 and 67
3 5 starboard drag spar 34 64 and 66
CA 02374576 2002-03-14
77316-13D
-21-
port lift spar 33 59 and 63
starboard lift spar 32 58 sad 62.
'Taken together, the series of rollers (40. 4Z, 44, 46, 48, 50, 52, 54, 56,
57, 58, 59. 60,
61, 62, 63, 64, b5, 66, 67), and additional rollers (port side) not
illustrated in Figures 18 and
19, secure the moveable wing cxteasion assemblies within the fixed wing
strucaire of the
compound wing, ensure smooth, rolling operuion of both wing extension panels
simultaneously, and maintain the proper aligaaxnt of the wing extension panels
in relation to
the fixed wing section. Figure 20 shows thin series of rollers in spatial
relationship, with the
reluive positions of the fined wing swcatre (1), starboard wing extension
panel (4) and port
wing extension panel (5) depicted in phantom lines (wing extension panels
fully rarxtsd).
Preferably, the positioning rollers described above will be made of metal,
e.g.,
aluminum, coated with a thin plastic or rubber skin.
A further illustration of the position and operation of the rollers is
provided by Figures
21. 22, and 23. Figure 21 provides a cross-sectional view of the forward lift
spar (30) and wing
exte~ion panel (4) of the starboard wing extension assembly (see, Fig. 16) a~
its position
relative to the fated wing strucwre (t), as maintained and secured by roller
ekmeota (e.g.. 40,
44. 56, 60). Figures 22 and 23 illustrate the operuion of the compound wing,
wing extension
. . panel (4) is raracted as a unit toward centerline (C). The wing extension
panel (4) is fully
rcQacmd in Figure 23, where tlx extension panel wing cap (36) mates with the
fixed wing tip
(38), and the entire wing extension panel (4) is enclosed within the fixed
wing structure (I).
The cooperative construction of the compound wing is further illustrated in
Figures 24,
and 26. which show various seaiooal views through starboard wing strucxvt es
(ref. Figures
13 and 15, saxian lines A-A. &B and C-C).
Referring to Figure 24, a sectional view taken on line A-A of Figure 13 aho~ws
the
2 5 structara of the s:ubosrd wing extension panel (4), as viewed along its
longiwdinal axles
toward the wing tip cap (3~. Several previously described fieatsurs of the
starboard wing
extenaian p~net (4) arc seen in cross-section: 'The leading edge slat ( 16)
(fated in position by
one a more strucnual rib extensions (73)). aileron (12) (pivaally aaached at
one or more
poi to the wing extenai~ panel (4) at str>uxural rib cxtemions (74) through
beuinga (75),
3 0 forward lift spar (30), drag spar (34), and aft lift spar (32). Guide bus
(11~ art visible in this
figure ~t ody oo the drag spar (34) but also on the web of the two lift span
(30 and 32).
Figure 24 further shows reinforcing stringers (28), which run subata~ially the
entire length of
the wing extension panel (4) and arc riveted to the underside of the clue skin
(26) of the panel.
Figure 24 additionally sho~wa clearance holes 76, 78, and 77, which are
provided to
3 5 accommodate the corresponding forward lift spar, drag spar, and aft lift
spa, respectively, of a
CA 02374576 2002-03-14
77316-13D
-22-
port wing extension panel as the two extension panels slide together within
the fixed wing
structure of the cea~ound wing. (See. Figure 26.)
Referring to Figure 25, a sectional view taken on line H-B of Figure 13 shown
the
srrucaues of the starboud wing extension panel (4), as viewed in a fully
extended position,
looking spanwise, toward the wing tip, from a point just inboard of the faced
wing tip (38).
Several previously described features of the cotnpound wing are seen in cross-
section; The
leading edge slats (14, 16), strucairal rib extension (73), positioning
rollers (40, 42, 44, 46, 48.
50), guide bars (11~, panel skin (26), stiffening or struc:aual rib (27),
ailerons (10 and 12),
swcairal rib extension (74), bearing fastener (75), guide rollers (52 and 54),
forwud lift spa
(30), aft lift spa (32), drag spa (34), and cleuatxe holes (76, 77 and 78).
Additional
strucaires of the fixed wing section are also visible in Figure 25, i.e., fore
and aft supporting
spas (68 and 69, respxdvely).
Referring to Figure 26, a sectional view taken on line C-C of Figure 15 shows
tlx
structures of the starboud wing extension panel (4), as viewed is a fully
retracxed position,
looking spanwise toward the wing tip, from a poittt just inboard of the fixed
wing tip (38).
Referring motneatuily to Figures 13 and 15, it will be apprxiated that in
contrast to the view
in Figure 25, the view of Figure 25 -is taken when the wing extension panels
(4 and 5 in Fig.
13) are fully reaactod. and thus many of the associated iataaal support
structures are
imermes6ed. Previously described features of the compound wing aeon in Figure
25 are also
2 0 seen here in noes-section: The leading edge slats ( 14, 16), structural
rib extension (73),
positioning rollers (40. 42. 44. 46, 48. 50), guide bars ( 11~. Panel skin
(26), stiffening or
swcxural rib (27), ailerons ( 10 and 12), structural rib extension (74),
beating fastener (75),
guide rollers (52 and 54), forward lift spar (30), drag spat (34), art lift
spa (32), main wing
supporting spars (68 and 69), and cleuance holes (76. 77. 78). Additional
structures, i.e., from
2 5 a port wing extension assembly that have retracted into this sectional
view of the stuboud
wing, are now seen: The foewud lift spar (31), with associated end block (11'n
and guide
rolkra (11~, which ate in rolling communication with the guide bar (116)
fastened to the web
of the focvvud lift apu (30) of the starboard wing extemion assembly: the port
drag spa (35).
with associated end block ( 118) and guide rollers ( 113), which ate in
rolling communication
3 0 with the guide bar ( 116) fastened to the web of the stuboard drag spa
(34); sad the aft lift spar
(33), with assaiated end block ( 11?) and guide rollers ( 115), which are in
rolling
communication with the guide bar ( 1 l6) fastened to the web of the aft IiR
spar (32) of the
starboard wing extension asstmbly.
From Figures 25 and 26 it will be appreciated thu cleu>Inae boles (76, 77, and
78) are
3 5 cut in each of the structural ribs (27), which ue spaced approximately 1-1
~h fen apart for the
CA 02374576 2002-03-14
77316-13D
-23-
length of each of the wing sections, in accordance with conventional wing
comroruction. These
passages (7G, 77, ~8) are sized and positioned to permit the wing extension
spars (31, 33, sad
35) of the port wing to pass through substantially the entire length of the
starboard wing
extension panel (4). Similar clearance holes will exist in each of the
saucdual ribs of the port
wing cxuosion asxmbly. Further detail of the relative positions of the
overlapping spars is
shown in Figure 36.
Exteasioa and retraction of the wing extension pane4s may be eff~d by any
means that
reliably moves both panels simultaneously. Differenaal extension or retratxion
of the panels
which results in bilaterally asymmetrical wing span will increase yaw and
result in loss of
directional control. Several suitable methods for actuating the components of
the compound
wing described herein will be apparent to those skilled in the art, however by
way of illustration
Figures 27. 28, and 29 depict two suitable mxhanisms.
Figure 27 depicts a cable system for retracting and extending the wing
extension panels.
In phamom lines, the starboard side of the fixed wing structure (1) is shown
enclosing the lift
and drag spars (30, 32, 34) of the starboard wing extension panel (4), and the
extension panel
(4) is fully extended. Also shown in phantom lines are the opposing lift and
drag spars (31, 33.
35) of the port wing extension panel: In the system illustrated bent,
extension sad retraction of
the wing extension panels is controlled by two control cables (158 and 159).
Optional
coordinating cables (301 sad 302) may also be provided as a safety measure, to
ensure that the
2 0 port sad starboud wing extension panels will always be extended ~
retracted to substantially
the same degree.
One end of cottaol cable 158 is attxhed to the starboard forward lift spar
(30) neat the
base of the wing esteasion panel (4). The cable (158) is threaded through a
pulley (161)
rotatably fixed to the fixed wing structure (1), through an anchor block
(304). through another
Z5 pulley (161) atmched to the fuel wing saxion (1), and the orbs end of the
cable (158) is
attached to the opposing port forward lift spar (31) near the base of the port
wing extension
panel (not shown). The anchor block (304) is auac6ed to a specific poi of tha
cable (i.e., the
midpoint). and the c~croi cable ( 138) caaaoc slide through the aachoc block
(304).
Alternatively, of courx, two cables could be employed wherein one end of each
cable is
3 0 aaached to the anchor bloct (304) sad the other erd of each cable is
attached to the port or the
starboard lift spar near the bax of the rapoaive wing eaneruion panels.
T~ set:ood control cable ( 159) is attached at one end of the starboard lift
spar (30).
threaded through a pulley (161) rotuably attached to the feed wing struawre
(1). through an
anchor block (303), through another pulley (161) rotanbly aaached to the fined
wing structure
35 (1), then attached to the end of the opposing port lift spar (31). Again,
the single control cab~c
CA 02374576 2002-03-14
77316-13D
-24-
(159) may alternatively be substituted with two cables. both attached to the
atx6or block (303)
at o~ end and t>ten attached respectively to either the port or starboard lift
spars.
A belt or chain ( 160) is attached to anchor block 303 at one end, threaded
around a
drive pulley ( 162), anti attached at the other end to anchor block 304. The
belt ( 160) is driven
by the drive pulley ( 162), which, in tuna, is controlled by a motor or
mechanism (n~ shown)
aaached w the main wing savcaire ( 1 ). In operation, when the drive pulley (
162) is rotated
counterclockwise, control cable 158 is pulled, and control cable 159 is
relaxed, t~reby drawing
the wing extension assemblies together (retracting the wing extension panels).
When the drive
pulley (162) is rotated clockwise. control cable 159 is pulled and control
cable 158 is relaxed.
thereby extending the wings. The arrows in Figure 27 show the direction of
movement of the
cables ( 158, 301, and 302) when the drive pulley ( 162) is turned
counterclockwise and the
extension panels are retracxed.
Because asymnxaic extension or retraction of the wing extension panels, e.g.,
due to a
comrol cable failure, would cause a lass of control characteristics, an
optional fail-safe
mechanism for keeping the movement of the wing extension panels coordinated
may be
employed and is illustrated in Figure 27. Two coordinating cables (301 and
302) are utilized:
Cable 302 is attached at one end to the tniddk of the starboud aft lift spar
(32) near the base of
. . ~ swing extension panel (4), thraded around a pulley ( 164) which is
aaac6ed to the
fixed wing section (1). then attached at its other end to the end of the port
aft lift spar (33): and
2 0 similarly, cable 301 is attached at one end to the middle of the port aft
lift spar (33) near the
base of the port wing extension panel (not shown), threaded around a pulley
(164) which is
attached to the fixed wing section ( 1 ), then attached a its other end to the
end of starboud aft
lift spar (32). In the event thu any of the coaQOl cabka (158. 159) fails, the
coordinating
cables (301. 302) would eaittre that the degree of exteanion or retrxtioa of
the port and
scarbomd wing extension assemblies would be subataatially the same.
Figure 28 is a detailed view of encircled portion XXVIII of Figure 27. All of
the
feaatra (drive pulley (162), anchor blocks (303, 304), control cables (158,
139), drive beh
( 160), pulleys ( 161. 164). starboard and port lift spars (30. 31. 32. 33).
starbos~rd a~ port drag
spars (34. 3~, and coordinating cables (301. 302)) are as described abm~e.
Arrows in this
3 0 figure show the diration of movement of the adjacent structure (pulley,
spar, or gable) as the
wing extension panels are reeacted by counterclockwise drive of the drive
pulley (162).
Alternative mahods for actuating a cable cocttrol system such as thu of
Figures 27 and
28 will be appartoc to those skilled in this art. For example. the anchor
blocks (303 and 304)
could be attx6ed to threaded nuts at either end of a leadscrew, instead of
being attaclud by a
3 5 drive belt ( 160) as illustrated
CA 02374576 2002-03-14
77316-13D
Referring to Figure 29, as aluraace method of extending and rtt~cang the wing
extension panels is shown. Most of the strucwral items of this figure have
been described
previously and are'the same as illustrated in Figure 27. Instead of the cable
control system of
Figure 27, however, there is a leadscrew (217) that extends from tip to tip of
the fixed wing
section ( 1 ). One end is threaded with a right hand thread and the other end
has a left head
chrad. An appropriately threaded leadscrew nut (218) is attaci>ed to the wing
extension panel
(4), and a leadscrew drive motor (219) is provided that is capable of rotuing
the leadscrew in
both clockwise and counterclockwise direcrions. Opcratiou of the drive motor
(219) cause the
leadscrew nut (218) to be pushed outward or pulled inward, depending on the
rotation of the
leadscrew, with a consequent extension or raracdon of the wing extension panel
(4).
The final aspax of the innovative compound wing of the present invention that
must be
addressed is the co-actuation of the ailerons of the fixed wing and of the
wing extension panels.
If the extension panel ailerons do not operate in concert with the fixed wing
ailerons, the .
airplane becomes much more difficult to control. Accordingly, the full
advantages of the
compound wing ascribed herein will not be realized without adopting some
mahanism for co-
actuation of the ailerons. Several mahaaisms will suggest themselves to those
skilled in the
art, and three such mechanisms arc illustrated in Figures 30, 31, 32, and 33.
Referring to Figure 30, which is a cross-sx~tional view taken s~long line J-1
of Figure
15, a partial view is shown of a starboard wing extension panel (4) retracted
within the fixed
2 0 wing structure ( 1 ). Several of the structural eleme~ such as support
spars. clearance holes,
and guide bars and rollers have been described previously and are the same as
depicted in
previous figures (see, e.g., Figure 26). An additional feature Shawn in this
figure is an aileron
actuuor plate (85) fastened to the fixed wing structure (1) by actuator plate
guides (87), which
permit sliding reorieamtion or pivoting of the accuuor plate (85) along guide
slots (86) cut in
2 5 the plan. in response to conventional actuation of the fixed wing aileron
( 10), through
conneaing arms (88 and 89). The aileron actuator plate (85) also acts as a
housing for two
guide roUat (52 and 54), which are in rolling communication with the
extet~tion panel aileron
(12). It is readily seen that movement of the fixed wing aileron (10) is
automatically trattalated
via the aihxon atxvator plate (85) and the guide rollers (52 and 54) to the
extension panel
3 0 aileron ( 12); and because the aileron actuator plate (85) is in contacx
with the extension panel
ailer~ (12) through mllaa (52 and 54), the acxion of the fixed wing aileron
(!0) is translated to
the extension panel aileron ( 12) during extension or retraction and
regardless of the degree of
extension or reaaaioa.
Figures 30 and 31 show two views of the same wing structures. In Figure 30,
the
3 S ailerons ( 10 and 12) are raised; and in Figure 31, ailerons ( 10 and 12)
arc lowered.
CA 02374576 2002-03-14
77316-13D
-26-
Comparison of these two figures illustrates the pivoting reorientation of the
aileron actuator
plate (85) and associated linkages (88 and 89).
Referring to Figure 32, a preferred mei6od of actuating the wing extension
aileron in
concert with the fixed wing aileron is shown. The fixed wing ailerons (10) are
controlled by
moves of a sliding actuator bar (103), which movement is translated to the
fixed wing
aileron ( 10) through a conventional arrangement of bellcranks and rods. The
actuator bar ( 103 )
runs through bar guides (122), which are fixod to the fixed wing section (1)
along the centerline
of the fuselage. The flaps are controlled by means of a control rod (30~, the
movement of
which is translated to the flap (72) through conventional lintcagea.
It is often advantageous to co-aca~ate flaps and ailerons to increase lift
(drooped
ailerons) or increase roll control (flaperons). Figure 32 illustrates a system
wherein, if control
rods 306 and 307 are co-actuated (i.e.. under cotmol of the flap lever), then
aileron (10) will
assist ttu: action of the flap (72).
For co-acwuion of the extension panel aileron (12) in concert with the fixed
wing
aileron ( 10), Figure 32 illustrates a cable system controlled by the same
sliding comrol bar
(103) that actuates the linkages to the fixed wing aileron (10). In this
embodiment, an aileron
actuator cable (105) is attached at one end near t~ end of the forward lift
spar (30), threaded
through an actuuor guide pulley (101) rotacably attxlxd to the fixed wing
sn~ux~ue (1), through
an aileron control pulley ( 157) rotacably attached to the control bar ( 103),
through another
2 0 actuator guide pulley ( 101 ) rotatably attached to the fated wing
strucaue ( 1 ), through another
guide pulley (i04) rotatably attached to the lift spar (30) near the base of
the wing exunsion
panel (4), then attached at its other end tv a sectioned pulley ( 100) fixedly
attxhed to the
extension panel aileron (12). A second aileron acaiator cable (106) is
attached at one end of the
sectioned pulley (100), threaded through a guide pulley (104) rotatably
attached to the aft lift
2 5 spar (32), through an acdator guide pulley ( 101 ) rotatably attached to
the fated wing section
( 1 ), through an aileron conarol pulley ( 157) rotatably aaached to the
aileron control bar ( 103).
through another acxttuor gui~ pulley (101) rotatably attached to the feed wing
structure (1),
then attached at its other end near the end of the aft liR spar (32).
It will be apprxiated from Figure 32 thu when the sliding ca~trol bar (103) is
moved.
3 0 this arrangement of cables ( 105. 106) and pulleys ( 101. 104. 15~ causes
one cable (i.e.. 105 or
i06) to slacken while the other cable tightens with respax to the sectioned
pulley (100), which
causes that pulley to rotate and thus raise or lower the extension panel
aileron (12) accordingly.
It wilt also be appreciated that as the wing extension panel (4) is retracted,
the entire wing
extension assembly, including the starboard lift spars (30 and 32) will roll
imvud, across the
3 5 longitudinal axis of the cottorol bar ( 103), but the relationship of the
cables ( 105, 106), control
CA 02374576 2002-03-14
77316-13D
-27-
bar (103), sectioned pulley (100) and aileron (12) is preserved: As the liR
spars (30 and 32)
roll across the-longitudinal axis of the control bar (103), the actuating
cable (105 and 106),
which are attached to the ends of the liR spars (30 and 32) will move as a
unit with~the 1iR spars
(30 and 32), sliding through the arrangement of pulleys (101, 157) but not
alttring the ability of
control bar movemems to be directly translated to the panel aileron ( 12).
A corresponding actuating system for the port side extension panel aileron is
indicated
in Figure 32 by the corresponding cables (120 and 121) attached to the port
fore and aR liR
spars (31 and 33), the ends of which are indicated by phantom lines. The
arrows in Figure 32
show the direction of movement of the components of the system when the
control bar ( 103) is
moved forward.
The bellcranks, rods, pulleys and cables depicted in Figure 32 are all of
standard
construction and are typically fabricated of stainless steel. The size
(diataeter) of the pulleys
(100, 101, 104, 157) and positioning of tht aileron coturol pulleys (157) with
respax to the
actuator guide pulleys ( 101 ) fixed to tlx wing section ( 1 ) will be
calculated so that the amount
of cable slack paid out or taken up by movement of the control bar (103) does
not exceed the
amount of cable required for the entire range of movement of the aileron (12).
Viewed another
way, it will be rcpt in mind that in the arrangement of cables and pulleys
illustrated bore. if the
. . aileron control pulleys ( 157), moving with the comrol bar ( 103), are
taken up to or beyond the
point of alignnxnt with the spar guide pulleys (101) through which the
associated cable (e.g.,
2 0 105, 106) is threaded, the aileron control pulley ( 157) would no longer
be in effective contact
with its associated cable, and movement of the control bar ( 103) world no
longer affect the .
tension of the actuation cables ( 105, 106). Pulleys accordingly will be sized
and positioned in
relation to each other so as to maintain control of tde aikrona.
Relating to Figure 33, an alternative system for co-acatarioa of the fixed
wing aileron
(10) and the extension panel aileron (12) is shown. In this system. cable
linkages are
resp~sibk for atxusdon of all ailerons ( 10. 12) and flaps (72), rather than a
combination of
cable linkages and conorol rods. bars and bellerank-type joints. (Cf. Fg.
.32.) The acatation
system for the extension panel aileron is essentially as depicted in Figure
32. For actuation of
the starboard fixed wing aileron ( 10) and starboard flap (72), the control
bar ( 103) is coat>eaed
3 0 to the fixed wing aileron ( 10) via two cable ( 124 and 125). Cable 124 is
fastened at one end to
the control bar (103). threaded through an inner aileron acatator pulley (123)
rotatably fastened
to a pivoting master flap actuator plate ( 156) (controllable by the pilot by
a mechanism not
shown here), through an aileron guide pulley ( 108), then fastened at the
other end to a sectioned
pulley ( 107) fixedly attached to the aileron ( 10). Cable 125 is similarly
attached, in opposing
3 5 fashion with respect to cable 124, as shown in Figure 33. A sectioned
pulley actuating plate
CA 02374576 2002-03-14
77316-13D
-28-
(155) fixtd to the main wing flap (72) is similarly attached, via two cables
(308 and 309),
through guide_pullexs (154) to the pivoting master flap acwacor plate (156),
as shown.
Ia operation, pivoting of the master flap actuator plea (156) by the pica
cauaa the flap
(72) and the main wing aileron ( 10) to move together. Fore-aft moveo~t of the
aczwtor
control ion wing aileron (12) co move in concert.
A corresponding actuating sysum for the port side extension panel and fixed
wing
section ailerons is indicated in Figure 33 by the correspoadiag cables (120
sad 121 for the wing
eauasion panel aileron; 126 and 127 for the fixed wing section aileron)
attached to the port fore
and aft lift spars (31 and 33) and the maser flap actuator plea (156),
respectively. Aa in Figure
32, the inboard end of a port wing exunsion panel assembly is depicted in
phantom lines. The
arrows in Figure 33 show the dirxtion of movement of the components of the
sysum when the
control bar ( 103) is moved forward.
The Engi and It-Driven Propellers
Preferred aircraft according to the present invention will employ as
innovative power
train and means of propulsion incorporuiag two engines, mounted inboard (i.e.,
within the
fuselage on the centerline of the aircraft), which drive (via a system of
drive belt;) two puaher-
type Propellers mounted on the wing ~or, moat preferably, on mounting
armatures such as
. . described previously that permit the position of the propellers to be
changed at the option of the
pilot. This propulsion system not only harmonizes with other aeronautical
discoveries described
2 0 herein. such as the bilaterally exundabk compound wing. the pivoting
mounting armatures and
the multi-purpose compound landing gear, but also eliminates many safety
hazards unavoidable
is conventional multi~engine aircraft, improves the efficiency of the airfoil,
eliminates gravity
loads that conventionally must be borne by the wings, offers greater protxtion
to the engines
sad lowers the aircraft's unur of gravity while utilizing space normally
wasted is conventional
aircraft, sad virtually eliminates the dangers ordinarily associated with
unexpxted failure of one
engine.
According to the present invention, two engines are mounted in the fuselage of
the
aircraft, in tandem and in oppaaed relation. ~iately aft of the cabin secxion,
undo the
wings. Referring momentarily to Figure 51, which is a cross-satiooal view of
the midsection
3 0 of as aircraft according to the invention, two aircraft engines (24 sad
25) are seen in silhouette.
Air~sooled aircraft engines, such as the sixtylit~er, horizontally opposed
Lycoming 10-540.
are suitable, however water-cooled automobile engines, such as a GMC 454-cubic
inch V-8
engine, would also be suitable.
The engines are preferably mounted, using conventional rubber engine mounts,
to a
3 5 steel frame, which frame is bolted to the fuselage. This permits easy
removal of the engines for
CA 02374576 2002-03-14
77316-13D
-29-
servicing or replacement. Moreover, if changes occur in the specifications for
the engines (or
changes occur in regulations governing the power rcquiremeots), the engines
can be switched
without the necessity of designing new external engine mounts, fairings or
nacelles, and without
refiguring the physics of the airfoil. Thus, even where the aircraft is in
mass production, a
complete alteration of the power plant can be implemented without interruption
of the
production line or retooling of production mxhinery.
Mounting two engines in opposed relationship permits the propellers to be
driven in
opposite dirations (counter-rotating propellers), without requiring one engine
to be a custom-
made counter-rotating engine. There are several disadvantages to multi-engine
aircraft with
propellers thu turn in the same direction. Such aircraft have a tendency to
yaw in one direction
(left or right) for several reasons rooted in the same-direction motion of
the. propellers:
Reaction of the aircraft to the torque required to turn the propeller,
asymmetric thrust due to
unequal angles of aaack of the upward-turning and dowmvard-turning blades, the
effax of the
twisted air flow behind the propeller, and gyroscopic turning moments. All of
these forces tend
co compromise tlx controllability of the aircraft, and the negative traits can
be amplified where
there is a differential power output to the propellers.
in an aircraft according to the invention, two identical engines can be used
to drive two
oppositely rotating propellers, and the disadvantageous rextion to torque,
asymmeaic thrust
and gyroscopic turning momem resulting from one rotating propellor are all
cancelled by the
2 0 opposite forces of a counter-rotating propeller. The turbulence behind the
propellers is also
balanced, and the aircraft rotational inertia is minimized by plxing the items
of greatest mass
(the engines) near the center of gravity. in addition, since the engine mass
is near the center of
the fuselage rather than on the wings. the of gravity is lower, which is
especially
beneficial to amphibious aircraft for taxiing and performing other optruioas
on the water.
2 5 In conventionally designed multi-engine propellor aircraft, the engines
are housed in
nxelks on the wings. Although the nxelles are. shaped to be as aerodynamically
harmless as
possibk, these is no escape from the fax the area of the wing surfxe taken up
by the nacelles
and aft of t~ nacelles provides no lift. and the nacelles themselves creue
drag. These
disadvantages are eliminated by plxing the engines inboard and modifying the
wing surface
3 0 only to the extent necessary to xcommodate the propeller mounts. The
efficiency of the
airfcaa~e is thus improved. '
Conventionally mounted propellerlengina on a multi-engine aircraft must be
located far
enough from the longitudinal centerline of the aircraft for the propellers to
clear the sides of the
fuxlage. This distance off the centerline makes conventional multi-engine
aircraft difficult to
3 5 control in the event of an engine failure, which requires immediate
correction of the asymmetric
CA 02374576 2004-07-09
77316-13D
-30-
thrust provided by the live engines) and sudden drag of the dead
propeller/engine if
uncontrollable~spia.er unintentional "wing-over" are to be avoided. These
hazards are
eliminated in aircraft according to the present invention, because by
employing a system of
overrunning clutches and a simple gearbox (see Fig. 37, discussed j>~, the
failure of one
inboard engine will not lead to the failure of either propeller. Rather, the
power from the
engine that remains in service is transferred instantly to both propellers,
requiring the pilot to
adjust only to the power reduttion and not requiring compensation for a sudden
imbalance of
thrust and responsiveness of the control surfaces.
Referring to Figure 34, the midsection of the aircraft pictured in Figure 15
is shown in
cross-section (view I-I). The relative position of the eagine (24 and 25) to
the fixed wing
structure (1) and the fuselage (300) is seen.
Figure 34 also shows, within the fined wing structure ( 1), the intermeshed
support
structures of fully retracted starboard and port wing extension panels,
including the forward lift
spars (30, 31) and guide rollers (56, 57, 60, 6l), starboard and port drag
spars (34, 35) and
guide rollers (64, 65, 66, 67), and starboard and port aft lift spars (32,'
33) and guide rollers
(58, 59, 62, 63). Support structure of the main fixed wing section (1) are
also shown,
including a forward main wing spar (68) and a rear main wing spar (69).
The two engines (24 and 25) drive overrunning clutches (109) which allow
torque
(power) to be transmitted in one direction only (in this case clockwix). In
the opposite
direction the clutche (109) turn freely. The rear engi~ (24) and its
overrunning clutch (109)
drive a shaft (172) on which a belt pulley (96) (or, alternatively, a chain
sprocka) is attached.
The belt pulley (96) drive a cog belt (99) (or chain), which cog belt (99), in
turn, goes on to
drive mechanisms in the port wing not seen in this figure. In addition to
driving the port belt
pulley (96), the rear engine shift (172) also drives a gear (184 in Fig. 37.
discussed ~ inside
2 5 a gearbox ( 110).
In like fashion, the forward engitx (25) and its overrunning clutch (109)
drive a forward
engine shaft (173), on which are attached a gear (187 in Fig. 37, discussed ~
in the gearbox
( 110) and a starboard belt pulley (95) (or, alternatively a chain sprocket).
This beh pulley (95)
drives a cog belt (99) (or chain), which runs to the starboard side of tlx
wing as shown is
3 0 Figure 34, and drives a pivot transfer pulley (94). The pivot transfer
pulley is attached to a
pivot transfer drive shaft (291 ) rocatably mounted in bearings ~(82) attached
to a forward upper
armature spar (70) and a rear upper armature spar (71 ). There is a co-axial
armature pivot shaft
(91) running through the length of the pivot transfer drive shaft (291) and
extending fore and ati
to armature pivot bearings (97), which are attached to the rear main wing spar
(69) at the
3 5 forward end and a rear auxiliary wing spar (98) at the aft end. The pivot
transfer drive shaft
CA 02374576 2002-03-14
77316-13D
-31-
(291) is therefore itself a tubular bearing, freely rotatabk about a co-axial
armature pivot shaft
(91 ).
Referring momentarily to Figure 1, it will be recalled that the propellers (8
and 9) are
preferably mounted on pivotally mounted armature (b and 7) that may be raised
and lowered to
change the position of the propellers relative to the wing (1). The cog belts
(99 in Figure 34)
driven by ctu; inboard engines (24 and 25 in Figure 34) extend, in this
embodiment, to the pivot
points of the armatures where the engines' power is transferred to propellor
drive belts
extending into the upper ends of the armatures (6 and 7) to drive the
propellers (8 and 9). Of
course, in embodiments thu do not incorporate the armature sttucaues disclosed
herein, the cog
belts (99) may extend directly to pulleys aaached to propeller shafts mounted
in the wings.
As shown in Figure 34, the starboard cog belt (99) drives a aaasfa pulley (94)
feed to
pivot aansfer drive shaft (29t), which extet~.s from a forward upper armawre
spar (70) to a
rear upper armature spar (71). Also attached to the pivot transfer drive shaft
(291) is a pivot
aansfer drive pulley (93). The spinning of the pivot transfer drive shaft (91)
and pivot traaifer
drive pulley (93) drive a propeller drive belt (84) (or, alternuively, a
chain), which extends to a
starboard propeller drive pulley and shaft (not shown). Alternatively, a
single rrnatabk pivot
shaft may be utilized in place of the co-axial shafts 91 and 291, but this is
less preferred, since
. _ then a constantly rotating pivot shaft would be a the of all the mourning
armaatre pivot
points. Another alternative would be to have a single stationary pivot shaft
and to have both the
2 0 cog bclt (99) and the propellor drive belt (84) cooaaxed to a single
freely spinning pulley
mounted on the pivot shaft (repluing the trarufer pulley (94) and the pivot
transfer drive pulley
(93)), or connected to separate pulleys which arc fastened togaha.
In the arrangetnern of drive belts shown in Figure 34, small idler pulleys
(90) adjust and
maintain a desired torsion in the belts (84 and 99). Staodtird, comaxrcislly
obtainable toothed
2 5 belts (timing belts) constructed, e.g., of steel reinforced rubber. may be
used throughout this
system. In the moat prt:fared embodiments, the compo~orts of the power train
will be
positioned so that all four drive belts (2 x 84 and 2 x 99) are the same
length. Likewise,
standard toothed pulleys, shafts and bearings used in modern aircraft
construcxion are suitable.
Propcr selection of the diameters of pulkya~ 83, 93, 94, 95, and 96 provide an
overall
3 0 speed reduction ratio that allows the engines (24 and 25) to run a a
relatively feat speed (4400
rpm, for example), for optimuat power production, while the propellers may
turn at a relatively
low speed, i.e., without approaching their maximum design speed (2700 rpm, for
example).
This propeller speed reduaioa eliminates the need for a costly spend reduction
gearbox uscd on
some existing aircraft engines.
CA 02374576 2002-03-14
77316-13D
-32-
Incidentally, the positioning of the engines, cog belts and propellers a
described above
places these majoraeurces of the aircraft's aoix behind the cabin uea. This
will result in an
aircraft that is comparatively quiet from inside the cabin, even though the
engines are inboard.
Figure 35 is a cross-xctional front elevation of the aircraft illustrating the
relative
positions of several components already discussed. The position in the fuxlage
(300) of the
rear engine (24) is shown in solid lines; the position of the forward engine
(25) is seen in dotted
lines. This figure shows how the starboard and port cog belts (99) extend into
the mounting
armatures (6 and 7) to actuatt the pivot transfer drive shags (291), at the
pivot points of the
mounting armatures (6 and 7).
Rotation of the pivot transfer drive shafts (291 ) causes propeller drive
belts (84) to turn
the starboard and port propeller drive pulleys (83), which arc attached to the
starboard and port
propeller drive shafts (81), to which the starboard propeller (8) and port
propeller (9) are
attached. Through these belt and pulley linkages, the power of the engines (24
and 25) mated
inside the fuselage (300) is transferred to the propellers (8 sad 9) mounta3
on the armaturas (6
and 7) (or, alternatively, mounted in the wings). The positions of idler
pulleys (90) is also
shown in this figure.
Figure 36 provides a plan view of the midsection of ao aircraft incorporating
the
compound wing, mounting armatarres sad internal engine mounting features of
the prat
invenaoa. Nearly all of the strucaires pictured is Figure 36 have been
described previously and
have the same item numbers as in previous figurGS (sae, e.g., Figures 1, 13,
16. 26, 34 sad 35).
The engines are represemed in this figure only by the shafts 172 and 173 (see,
Figure 34).
Additional preferred auxiliary spars for the wing (98) and for the mourning
armature (119) are
shown here and were not inchtded is previous figures.
The interlocf~ing relationship of the support structures of the extendable
wing panels (4
and 5) is clearly s6owo in Figure 36. With the extension panels (4 and ~ in
partial extension.
as shwva, the starboard and poet focwud lift spars (30 and 31), the starboard
sad port drag
spars (34 sad 35), sad the starboard and port reu lift spars (32 and 33) are
saes to overlap
within the enclosing structure of the fixed wing section (1). From this figure
it is seen that
whoa the wing exteruion panels (4 and 5) are fully reQacted within the fixed
wing structure ( I ).
each of the wing exteasioo asxmblies extends across nearly the entire (fixed)
wing span, i.e..
from wing tip to wing tip.
Figure 36 also shows the plan of the drive belts (84 sad 99) that cansfer the
power
provided by the engines (represented here by shafts 173 and 172) to the
propellers (8 sad 9).
Assuming clockwise rotation of the opposed engine shafts ( 172 sad 173), the
arrows in Figure
3 5 36 show the direction of the belts (84 sad 99), which produces inwardly
counter-rotating
CA 02374576 2002-03-14
77316-13D
-33-
propellers. Inward counter-rotation of the propellers is preferred. As an
added safeguard, the
single drive belts X84. a~ 99) shown in Figure 36 and other drawings (e.g.. 99
in Figs. 37, 38.
41) may be replaced with two, or more preferably three (or more) parallel
drive belts, arranged
side-by-side and separated by sheet metal dividers. 'The plural drive belts
would provide
continued power aaasfer to the propeller in the event of the failure of one
belt. The dividers
would prevent a failed belt from interfering with an operating beh.
Referring to Figure 37, a diagram of the simple gearbox (110 in Figure 34) is
shown.
T6e gearbox permits power from one engine (24 or 25) to be automatically
transmitud to both
propellers, in the event of the other engine failing or being shut down.
Diaeagagiag the gears,
by means of a gearing control um (111), makes the rotation of the propellers
completely
independent.
T'he gearbox (110) pretierably houses five gears (184. 185, 186, 187 and 315).
Gear
184 is driven by the rear engine (24); gear 187 is driven by the forward
engine (25). T1x two
gears 185 and 186 are idler gears, and gear 315 is an idler gear thu can be
moved along its
shaft (see double-headed arrow) by means of the gearing comrol um (111) while
in motion.
T'he moveable idler gear (315) can be positioned so that it is disengaged from
idler gear 185
(pictured), or it can be poaitiooed so as to mesh via dogfaa sprockets
(unnumbered) with gear
. . 185. The. idler gears 185 and 315 in Figure 37 may alternatively be
replacxd by a single
moveable idler gear that can be mound to engage both gears 184 and 186.
2 0 In the fully eagagod position. the gears ( 184, 185. 186, 187 and 315) in
the gearbox
( 110) cause the pulieya, belts, and propellers in this design to operate as
o~ system (i.e., both
propellers run at the same speed). With the gearbox disengaged, the front
engine (25) and the
port propeller (9 in Figure 36) and associatred pulleys and heirs run as a
separate system from
ttk rear engine (24) and the starboard propeller (8 in Figure 36) and
associated pulleys and
belts. In the disengaged eoofiguruioa the aircraft operates much like a
comeationa! cwin-
engine aircraft, at last in terms of the independence of the two propulsion
systems. A grew
safety advantage is realized when tl~ gars are engaged: The two propeller
drive systems are
conned by mans of the garbox to each other, so that if power from one engine
should be
compromised the other engine would automatically provide power to both
propellors evenly
3 0 without requiring the pilot to take corrective action. Thus, with the gars
engagtd, a single
engine shutdown does not lead, as in conventional multi-engine aircraft, to
the aircraft being
suddenly asymmetrically powered, and consequently the aircraft atxordittg to
the im~ention
acquire the performance advantages of multi-engine aircraft while achieving
the operating
simplicity of singktngine aircraft, and they realize the best of the ssfay
charaaaristics inherent
3 5 in each type of aircraft.
CA 02374576 2002-03-14
7?316-13D
-34-
The capability of unifying the power trains of all propellers through a simple
gearbox as
just described-v~'till~ive several carry-through advantages in subservient
systems t6u may also
be unified correspondingly. For example, in conventional enginelpropeller
systems, a separate
propeller governor geared to the engine provides a means of adjusting the
pitch of the propeller
blades to maintain a speed set by the pilot. In accordance with this
invention, both propellers
may be driven at the same speed through a common gearbox, thus individual
propeller
governors to set the speeds of the propellers is not necessary. Instead, ~atu
such as as
automatic hydraulic selector valve may be provided so that engaging the gears,
e.g., via gearing
codarol arm 111 (Figure 3'n, will automatically select o~ propeller governor
to conaol ail the
props, leaving the remaining propeller governors) as safety backups.
A particularly innovative feature of preferred aircraft according to this
invention is the
incorporation of pivotal mounting armatures, already discussed with refrcence,
e.g., to Figures
1, 4, 6, 7, 34, 36 (and many of the other drawings). Further appreciation of
composition and
function of the pivotal mounting armatures will be gained by reference to
Figures 38, 39, 41,
and 42, which show starboard and port mounting armatures isolated from the
body of the
aircraft but in proper spatial relationship to each other. as if they were
installed on an aircraft in
aaordaoce with the teachings herein.
Referring to Figure 38, opposingly positioned starboard (6) and pmt (7)
mounting
2 0 armaaires are shown in perspective, in thr oriemation they would have ia.
e.g.. an aircraft as
pictured in Figure 5 (landing gear retracted, propeller centers level with the
wings). Flotadonal
pontoon landing gear (22 and 23) are incorporated in or mounted at one end of
each mounting
armature (6. ~). and a starboard caster-type stabilizing wheel ( 18) is shown
retracted into a
rece.~aa in the starboard pontoon (22) (the like port caster-type stabilizing
wheel is not visible
2 5 in this view). The piva points of each armature are indicated at P im
Figure 38, and it is
through the piva poims that the mourning armatures (6 and 7) are pivotally
fixed to the main
wing sttvcaue (1 in Figure 36) by a pivot shaft (91 in Figure 36). The
Propellers (8 atd 9,
indicated by cinvlar arcs in Figure 38) are mounted at the opposite end of
either armtawre (6. 7)
from the landing gear. in nacelles (314) formed in the surface of the
armatures. The beh-and-
3 0 pulley drive system for the propellers. discussed previously with
refetrncx to Figures 34. 35
and 36, is recalled in this figure by the partial cog belt (99) and the pivot
transfer drive shaft
(291 ). The propeller drive belt (84 in Figure 36), and the propeller drive
pulley and shaft are
uxlosed within the mounting armature and thus are mot visible in this drawing.
The pivotal mounting armatura of the present imverttion provide a means of
35 coordinating the placement of the propellers and the exposure of different
types of IandinR gear.
CA 02374576 2002-03-14
77316-13D
-35-
It will be appreciated by reference to drawings such as Figure 38 that the
campourtd ia~ing
gear mounted at t~_lower ends of the armatures are rcpt at substantially the
same distance from
the propellers mmtnted on the upper ends of the armatures. But while the
separation of landing
gear and propellers remains constant, their orientation with respetx to the
rest of the aircxaft
(and the ground) may be changed, baaux of the pivotal attachment of the
armatures to the
fixed wing swcture ( I in. Figure 1 ) of the aircraft.
Referring to Figure 39, the armatures (6 and 7) may be considered as having an
upper
end (or propeller cad) and a lower end (or landing gear end) with respect to
the pivot points (P).
For example, the upper end of armature 7 in Figure 39 is indicated by the
screwed line U-U,
and the lower end of the armature 7 is indicated by the screwed line L-L.
While not wishing to
be limited to one particular shape or any particular set of cenerete
dimensions. the preferred
mounting armatures depicted in the drawings may be broadly described as
incorporating four
segments, at differing angles to one another, indicated as W, X, Y, and Z in
Figure 39. A
dashed line represents a centerline through all four xgments of mounting
armuure 7, It will be
appreciated chat segments W and Y are substantially perpendicular to exh
other. since. in the
orientation illustrated hers, xgment W is coextensive with the wing sttucarre
and Segmem Y is
coextensive with the fuselage. The relative angle of xgment X, which connects
segments W
and Y, may vary widely according to design choitxs but ideally is sufficient
to accommodate the
angle of a single drive belt (e.g., 99 in Figure 35) extending from the
inboard engine shaft (172
2 0 or 173 in Figure 34) to the transfer pulleys on the pivot shafts (e.g.,
291 is Figure 35). The
angle of xgment Z, which extends inboard from segmem Y, also tray vary widely
in
accordance with design choice but ideally is sufficient to conform the angle
of tlu segment Z to
the angle of ttu keel of the hull-type fuxlage (300 in Figure 35). The barrier
dimensions of the
armaatres will geoaally follow the centerline but may taper and curve in order
to provide
2 5 fairing, to improve the fit of the armature into recesses, or to mare the
outer surfaces of the
armantrea aerodynamically smooch or capable of merging with an xrodyttamic
surface (i.e..
wing or ft~elag~e).
Referring again to Figure 39, the praise dimeaiioos of the xgmeots W, X. Y and
Z
may vary, so long as at least one object of the invention is accomplished.
Segment W must be
3 0 long enough to prevent the propeller blades (8 and 9) from striking the
fuselage a all points of
rotation of the armatures and must not be so long that a the atmanttes'
fartheu rotation away
from the fuselage (see, e.~.. Figure 9) the propellors (8 and 9) mounted in
the upper end (U-U)
physically interfere with each other. (Slight overlap of tlu propeller arcs
may be
accommodated, however, by fore-and-aft staggering of the propellers.) The
dimensions of
35 segments X. Y and Z together cannot be so long that the lower end (L-L) of
the armature ~s.r .
CA 02374576 2002-03-14
77316-13D
-36-
the pontoons 22 and 23) fait to clear the waur during a water landing. That
is, at maximum
rotation of the ~rmat8res away from the fuselage (see, e.g., Figure 9), tlu
pontoons (22 and 23)
must be above the waur line of the fuselage. It will be additionally
appreciated, referring
briefly to Figures 6-10, that the mounting armatures (6 and 7) are shaped such
that deployment
of the stabilizing landing gear to any of the landing positions places the
tower end of the
armatures outboard of the pivot point, and therefore the forces encounured on
landing and to
open rather thaw to collapse the armaaues and landing gear. In accordance with
these factors,
in an aircraft according to this invention having the dimeosioos rexited ~ for
a most
preferred embodiment having the general configuration illustrated in Figure 1
(see page 13), by
way of illustration and not of (imitation, the dimeosioos of the mourning
armaaires would be as
follows: Segment W, 44-48 in. (1.12-1.22 m); segmtat X. 19-24 in. (0.48-0.61
m): segment
Y, 34-38 in. (0.86-0.965 m): segment Z. 28-32 in. (0.71-0.81 m); angle a
(between W and X),
145 ° to 155 °; angle ~ (between X and Y), 115 ° to 125
°; and angle y (between Y and Z). .110 °
to 130°. The most preferable dimensions for this particular embodiment:
W, 46 in. (1.17 m);
X, 21.5 in. (0.546 m); Y, 36 in. (0.91 m); Z, 30-31 in. (0.77 m); a,
150°; ~. 120°: y, 120°.
Referring to Figure 40, a cross-section of the starboard wing (ref. Figure 3)
is shown,
where the mounting armature (~ is rotated fully inboard. so that the upper end
of the mounting
armature has merged with the fixed wing strucarre (1). Figure 40 shows a
smooth aerodynamic
surface provided by the now juxtaposed wing strucaue (1) and mounting armature
(6). Within
the armature housing, tix propeller shaft (81) is seen to extend from the
starboard propeller (8)
through a bearing (82) in the rear upper armature spar (71 ) to a bearing (82)
in the forwud
upper armature spar (70). The split flap (72) of the fixed wing saxion (1) is
shown in raised
position. and the leading edge slat of the main wing section (1) is shown
fully retracted.
Referring to Figure 41, the two pivotal mounting armatures (6 and 7) are shown
as in
2 5 Figure 38, except thu body armawres have been rotated around the pivot
points (P) to be in the
appropriate orieatadon for landing on a hard surface or rumvay. Rotation of
the armawres to
the position illustrated brings the stabilizing wheels ( 18) into position for
landing. The wheels
are swung out from the recesses in the pontoons (22 and 23, ref. Fig. 38),
e.g., by mans of an
actuating lever linked to one segment of a multilink actuating strut (not
shown, discussed j~).
3 0 The propellers (8 and 9), in this orientation, are raised far enough above
the wing so that
substantially all of the arc of each propeller is above the wing. 'Ibis is
advantageous for takeoff
and landing attempts, because the propeller blades in raised position are less
likely to encounter
debris from the ground ark the propeller wash is directed over the control
surfaces of the tail
secuon.
CA 02374576 2002-03-14
77316-13D
.37_
Referring to Figure 42, the two pivotal mounting armatures (6 and 7) are shown
as in
Figure 38, exctptttrat both armatures have been rotated uound the pivot poima
(P) to be in the
appropriate oriernadon for landing on water, i.e., the pontoons (22 and 23)
have been rotated
into the appropriate position, the stabilizing whetis ( 18) have been
retiracted, and the propellers
(8 and 9) have bean raised to their maximum distance above the wing. In this
orietuation, the
propellers are shielded by,the wing from water spray, and the pmp wash is
conducoed more
directly over the control surfaces of the tail section. The increased downward
lift caused by the
prop wash over the tail sxdon partially counteracts the undairabk forward
(nose-down) pitch
that results from raising the thrust line. It should be recalled, however,
that even though the
thrust line is raised by rotation of the armatures, the cxrna of gravity does
not change
appreciably, since the mass of the engines remains below the wings, in the
fuxlage.
Referring to Figure 43, a cross-secd~ of the starboard wing (ref. Figure 1) is
shown.
where the mounting armature (6) is rotated partially outboard, so that the
upper end of the
mourning armature is raised above the fixed wing strucutre ( 1 ). W itlun the
umature housing,
the propeller shaft (81) is seen to extend from the starboard propeller (8),
through a bearing (8Z)
in the propeller nacelle bulkhead ( 112), through another beuing (82) in the
rear upper armature
spa (71 ), to a bearing (82) in the forwud upper umaatre spar (70). A
propeller drive pulley
. . (83) is aaached to the propeller shag (81) and is turned by a propellor
drive beh (84). which
extends down to a pivot transfer drive pulley (unnumbered) aaached to a pivot
transfer drive
2o shaft (291). A transfer pulley (94) also aaacbed to the piva aa~fer drive
shaft (291) is turned
by a drive belt (99). The split flap (72) of the fixed wing section ( 1 ) is
shown in a lawut~ed
position, and the leading edge slat (14) of the main wing section (1) is shown
fully extended.
The mounting armatures of the presern invention may be acwatrad by any
conventional
means that serve to rotate the armatures about their pivot . Prcssuro-driven
(e.g.,
2 5 hydraulic, air) or screw~riven rods, for instance, that are set
transversely in the fuselage and
zee exaaded 6aizoncally to push the lower ends of the armsotutes away from the
fuselage may
by utilized, or gar~drivea pivots (P in Fig. 42) may also be employed. These
mechanisms,
however. have diaadvat>uges relating to the pt~ecision with which the a:mantte
extension can, be
controlled sod relating to the abaoc~ion of landing stresses.
3 0 The preferred actuator mechanism for extending and raracxing the pivaally
mounted
armatures according to this invention is a multilinic xtuator strut such as is
depicted in several
of the frontal elevation drawings discussed previously. (See, for example,
items 280 and 281 in
Figures 6. 7. 8. 9 sad 10.) Reftrring fast to Figure 9, in which the multiiidt
xtuator struts
1280 and 281) are at their fullest extension, the struts zee seen to form
(with the fuselage and thr
35 armatures) an amngemetu of two bxlc-to-bxlc 4-bar lidtages.
CA 02374576 2002-03-14
77316-13D
-38-
For each multilink actuator strut, a series of four rectangular links,
connected end-to-
end and togeth~t measuring the proper length to achieve the maximum desired
outboard rotation
of the mounting armatures, is attached at one end to the fuselage and at the
other end to the
lower end of the mounting armature. These connections leave three joitus in
the series of four
links between the fuselage and the mounting armature. A fifth link is auached
at one end to the
center joint in the 4-link series and is attachod at the other end high on the
fuselage, so that the
fifth link, the fuselage and the inboard two links of the 4-lint series form a
4-bar linkage. Two
hydraulic (pictured) or screw-driven actuators are conned to the 4-link series
so as to permit
collapse (independently) of the outboard two links and the inboard two licks
at the unbraced
joints. Hy collapsing the inboard two links, an intermediate positioning of
the armatures is
achieved (see, Figures 6, 7 and 8); and by collapsing both the inboard two
links then the
outboard two links, the entire 4.-link series is folded imo the fuselage (sae,
e.g., 280 and 281 in
Figure 35), and the armatures are fully retracted.
The links of the multilink actuator struts will be sized to provide the exact
positioning of
the armatures necessary to deploy the desired configuruion of landing gear or
propeller
position. Collapse of o~ or both of the 4-bar linkages of the multilink
actuator struts will
provide automatic "stops" to the mounting armature rotation, eliminating the
need to calibrate
the pressure or screw-driven components of the actuator system.
2 0 A further innovative feature of preferred aircraft according to the
invention is the
incorporation of compound landing gear that enable the aircraft to be modified
in flight for
landings on a variety of surfaces (waur, hard surface, snow). Prior to this
invention, them
were no aircraft capable of safe landings and takeoffs from all of water,
tarmac and snow, and
certainly no aircraft that could be modified to land on any of those surfaces,
at the option of the
2 5 pilot, while still in flight.
Aircraft incorporating the compound landing gear described herein will not
only have
the capability of landing on many surfaces, they will realize additional
advan<ag~s from the
particular design of the compound landing gear. For example, the compound
landing gear of
the present invention is expected to provide more efficient transmission of
the inertial load to
3 0 the ground on hard landings. In addition. the utilization of slti-type
gear thu may be retracted
to be substantially flush with the fuselage is expected to provide a sboclc-
absorbing effax in the
event of a "wheels-up" landing (belly landing). Also, having the primary
landing gear descend
from the fuselage requires shorter landing gear mounts (compued with wing-
mounted landing
gear) which have a lower bending moment and are thus less apt to collapse from
incidenul
CA 02374576 2002-03-14
77316-13D
-39-
!octal loads, such as from tight radius turns a coo high a speed, la~inga with
incorrxt drift
correction, .or even collisions with ground vehicles.
'The compound aircraft landing gear of the present invention include three
eomponems:
A) a forward landing gear component positioned forward of the ~r of gravity of
the aircraft, substantially completely rea~actable into the fuselage,
including
integrated steerable siti and sceerable wheel subcomponet~;
H) a main central landing gear componeat, substantially completely retractable
into
the fuselage, including integrated skis and stxrable wheel subcomponetm. exh
of which may be deployed to a point 8-13° (preferably 10-11 °)
aft of the center
of gravity of the level aircraft sad which, wtua retracted, assist in
foctnuion of
(or retract to form) a step in the fuselage at a point 8-13°
(preferably 10-11 °) aft
of the center of gravity of the kvtl aircraft; and
C~ a latrral stabilizing gear component comprising two bilaterally situated
stabilizing members, each of which may be deployed on either sib of the
aircraft t0 a point 8-13° (preferably 10-11°) aft of the comet
of gravity of the
level aircraft and substantially aligned with the main ceaaral landing gear.
and
each member including integrated pontoon and wheel subcomQoneats.
The subcomponcnts of each component of the compound landing gear will be
mwated
in such a way that each of all the w6ee1 subcon>ponents, or all the ski
subcompooems, or all the
pontoon subcomponezns will be separately deployable to act as the primary
laadiag gear for the
aircraft, thu is, deployable to a position where the wheels, or the skis. or
the pontoons becoate
the lowest points of the level aircraft with respect to the ground (i.e., the
points of cotuatx with
the ground during s landing operation). Preferably. the forward and rosin
cemral landing gear
will be mounted in such a way thu whoa fully reaacued the shi-type gear will
nestle into the
fuselage opatiag through which the gear are deployed, and the bottoms of the
atria will be
substantially Hush with the outer surfacx of the fuselage. thereby eliminating
the need for
enclosing nose and gear bay doors. (Ses. Figure 44, position of skis 29;
Figure 50, position of
skis 147.) Most preferably the subcomponents of each landing gear component
will be
integrated in such s way that, wherever possible, full depfoyu~ of one
aubcompooenc will
3 0 automuically prevent full deployment of another subcomponent, so that no
two sets of landing
gear may be inadvertently deployed to their fullest extent and become,
collectively, the primary
(lowest deployed) landing gear for tl>e aircraft. The moat preferred
embodiments will, howevrr.
permit coordinated xtion of the subcomponems where it is sdvaarageoua, for
example, in
providing ski-type landing gear thu can be raised to a level just slightly
above the lowest point
CA 02374576 2002-03-14
77316-13D
-40-
of the tires of the wheel gear, which is the best configuration for landings
on intermittent snow-
covered and cleu hard surfaces. (See, Figures 46 and 57.)
As described below and with reference to the drawings, aircraft incorporating
the
compound landing gee of this invention ue uniquely serviceable anti safe.
Figures 44, 45, 46, 47, 48 and 49 illustrate the deployment and operation of a
preferred
forward lording gee component of a compound landing gee according to the
invention. The
same structural members are shown in each of these figures at different stages
of deployment.
The reference numbers for each of the members ue the same from figure to
figure.
Referring to Figure 44, a forward loading gear asxmbly is shown having the
esxntial
forward landing gear component functionalities, namely, full retractability
within the fuselage
(300) of the aircraft, sepuate deployability of either wheel or ski
subcompoaents, and
steerabiliry of the skis and wheels once deployed. As illustrated, the forward
landing gear
component is comprised of members for positioning (i.e., deploying of
retracting) the wheel
gee and ski gear, members for acntating tht positioning of the gee relative to
the aircraft,
members for pasicioaing the ski gear subcomponem relative to the wheel
subcomponera, and
(preferably) numbers for absorbing landing forces (i.e.. one ~ more shock
absorbeca or
springs). The neural steering mechanism has been omitted for the sake of
clarity. Also, a
braking mechanism will typically be included but is not illustrated here for
the sake of clarity.
Referring again to Figure 44, the subcomponeats of the forward landing gee are
embodied in a sceerabk wheel (21) (or, alcernuively, two stxrabk whoela),
preferably having a
pneumatic tire, and two skis (29, port ski only is shown), connaxed to the
front wheel ask
(208) by a front ski actuacoc link (204). which connats to each ski a a
pivotal mount (209).
The whxi (21 ) of courx turns freely on its ask (208). but the ski pivotal
mavnta (209) have
stops (na shown) that win limit the arc that can be described by the skis, to
prevent the skis
2 5 from ranting so far forward or backward that the aircraft can nose into
the scow ~ bosom out.
during s ano~w land'rog.
The ask (208) of the fmnc w6x1 (21) is connected by a tubule stewing column
(316)
(or shaft) to a steering conaol plate ( 193). A swing-out mounting cylinder
(230) nets as a
housing fot the stewing colunm (316), within which the column is freely
rotatabk by accuuion
3 0 of the steering control plate ( 193). The acatal staring mechanism,
through which the stewing
control plate ( 193) is auo<d. is not shown here. but prefwably the stewing
mechanism (e.g..
steering cables or simile trn;chanism (ref. Fig. 60)) is attached to the
stewing control plate
( 193) in such a way that the control plate ( 193), and ttrerefore the frotu
wheel (21) and skis
(29), become steerable only when they ue lowered for Landing: That is, the
steering column
3 5 1316) can be rotated within the swing-out mounting cylinder (230) only
whey the mounting
CA 02374576 2002-03-14
77316-13D
-41-
cylinder (230) is swung-out to as approximately vertical orientation with
respax to the aircraft.
When the swing-~uii mounting cylinder (230) is rotated to a substantially
horizontal position
with respect to the aircraft, as shown in Figure 44, the steering mechanism,
preferably, will not
be able to actuate the steering control plate ( 193) or otherwise cause the
forward landing gear
(28, 29) to swivel.
A ski deployment actuator (205) is pivotally attxhed at one end (206) to the
staring
control plate (193), and pivotally attached at its other end (207 in Figure
45) to the front sri
actuator link (204). With these attachments and links, the front sici acatacor
(205) will turn with
the steering control plate ( 193), whxl (21 ) and skis (29); furthermore, the
actuator (205) at this
position allows the differential deployment of either the whxl gear (21) or
the ski gear (29), as
shown in Figures 48 and 49. The front slti actuator (205), as well as the
other actuators in the
landing gear assemblies, may be povve:~ by any suitable means, dtpending on
taanufxauer's
preference. Hydraulic cylinders, air cylinders. eia~ screw jxirs and eves hand
craahs are all
known for this sort of mahanical task, It will also be appreciated that
although the foregoing
description discusses single lilts and actuating arms, certain of the members
described may
advantageously be iattalkd in pairs. For instancx, it is mentioned that two
sltia (29) are
typically (and preferably) employed in the forward landing gear component; and
accordingly
two accuuor links (204) may be employed (iasttad of a single. U-shaped
acutator link
connxting both skis and pivotally mounted around the from wheel axle (208)),
which, in turn,
2 0 would necessitate dual front ski actuators (205).
The forward landing gear (21, 29) and associated links and steering asxmblies
described previously and as mounted in the swing-out mouaring cylinder (230)
are coa~cted to
the fuselage (300) via a front gear suspension lids ( 190) and a front gear
connecting link ( 197)
thu is further pivotally conax~ed to a front gear actuator link ( 198). The
suspension link is
2 5 pivotally attached to the fuselage 1300) at one end ( 191 ) and pivotally
attxhed at its other end
( 194) to the upper end of the swing-out mounting cylinder (230). The mounting
cylinder (230)
has a fm-like mounting appendage (317) projcaiag generally perpendiatlarly
from the
cylindrical dousing for the tubular staring column (316), extending diraxly
aft when the
mounting cylinder is in an upright (vertical) orientation. The front gear
correcting link ( 19'x) is
3 0 pivotally attached at one end ( 195) to the swing-out mounting cyiinda
(230) at a pivot on this
mounting appendage (317) and pivotally attached at its other end (200) to the
front gear actuator
link ( 198), which, is rata, is pivotally attached to the fuselage at a pivot
( 199). The front gear
acwator link ( 198) also provides a pivot attxhmcnt (203) for a front gear
xtuator (201 ), which
is pivotally attached to tla: fuselage as icy ocher end (202). The mounting
appendage (317) also
CA 02374576 2002-03-14
77316-13D
-42-
prw~a a pivotal m~in~g point (196) for a shock absorber or spring (189), which
is pivaally
aaached at its otheE end (192) to the fuselage (300).
Hy reference to the foregoing description and the drawings (Figure 44-49), it
will be
appreciated that actuation of the aforementioned series of linkages causes the
swing-out
mounting cylinder (230) to rotate generally in the sagittal plane of the
aircraft (i.e.. the plane
including the centerline and dividing the aircraft into symmetric halves),
thus deploying or
retracting the forward landing gear (wheel (21) and skis (29)). Furthermore,
shortening of tlu
front ski actuators) (205) deploys the skin (29) over the front wheel (ZI)
(see. Figure 49).
During extension at retraction, the shock absorbetlspring ( 189) remains at
its full length, since
it does not support say of the weight of the aircraft. (See. Figures 44, 45
and 46.) In couching
down for a Landing (Figure 47) and while operating on the ground (Figures 48
and 49), the front
gear actuator (201) remains at its fully extended length, and the front gear
acata~tor link (198)
does not rotate, so that the connecting link (197) holds its position. and the
shock
absorber/spring ( 189) compresses and dxompresses as the landing or taxiing
load varies.
To position the skis (29) for operation on a snow-covered surface, the front
ski actuator
(203 is extended. which rotates the front ski actuator link (204) about the
from wheel axle
(208). (See, Figures 48 sad 49.) On surfaces completely covered with snow it
is desirable to
position the skis (29) below the wheel (21) to climiaate drag from snow
accumulating in front of
the wheels, however during operation on surfaces where snow only partially
covers the grout
it is desirable to position the skis so that the tires of the wheel (21)
exceed slightly below the
skis (29), so that the aircraft rides up oa the tires where there is no snow
but rides on the skis
(with the wheels providing minimum drag) where the snow covers the ground. In
order to raise
or lower the skis (29) this small amwnt relative to the wheel (21), the front
ski actuator (205) is
raraaed slightly from its full extenai~. which rotates the support (204) and
lowers the skis
2 5 (29) aliglttly.
Figures 30, 51. 52, 53. 54. 55. 56. 58, 37 and 59 illustrate the deployment
sad
opaadon of a prefecrod main oeaaal landing gear compost of a compound loading
gear
according to the invention. The same swcauat n>embers are shown in each of
these figures at
different stages of deployment. The reference number for each member is the
same from figure
3 0 to figure.
Referring to Figure 51, a main cxotral leading dear assembly is shown having
the
essential main central landing geu componem futrctionalities, namely. full
retracxability within
the fuselage (300) of the aircraft sad recractability to form a step in the
hull (necessary to permit
takeoff from water). separate deployability of either wheel or ski
subcomponents, sad
35 steaability of the wheels once deployed. Ac illustrated. the main cxnaal
landing gear
CA 02374576 2002-03-14
??316-13D
r43-
component is comprised of members for positioning (i.e., deploying or
retracting) the wheel
gear and ski= gear. ~mbera for acwuing the positioning of the gear relative to
the aircraft,
members for positioning the ski gear subcomponent relative to the wheel
subcomponent, and
(preferably) members for absorbing landing forces (i.e., one or more shock
absorbers or
springs). The actual staring mechanism has been omitted for the sake of
clarity. Also, a
braking mxhanism will typically be included but is not illustrated here for
the sake of clarity.
Referring to Figure 50, a saxional side elevation of the midsection of an
aircraft
according to the invention is shown, illustrating the general positioning,
within the fuselage
(300) and fated wing section (1), of the major systems std structures, e.g., a
wing extension
panel (4) sad associated structures (unnumbered), the engines (in silhouette,
25 and 24
(partial)), the lower end of a port pivotal mounting armature ('n including a
pontoon sxdon
(23). The approximate position of the aft-most passenger within the aircraft
is repraeated by
the seated human figure (unnumbered). Figure 50 shows the position that the
main skis (147)
occupy in the fuselage (300), and shows the position that the arasature (?)
and pontoon (23)
occupy in the fuselage, when the aircraft is configured for cruising flight.
(Cf. Figures 3 and
9.) Full recaction of the main cxawal landing gear and of the mounting
armacura brings the
main skis ( 147), a main wheel hatch ( 148) and the poatoot~ (23) of the
mwnring armatures into
. . alignment. flush with the fuselage (300). creating a smooth outer surface.
In the preferred
embodiment illustrated, it will be noted thu complete retraction of the skis
(147) brings the nose
2 0 of the skis up into the fuselage (300), forming a slight notch ~ mini-step
(arrow) in the
fuselage, below the water line. Advantageously. this hatch helps to ventilate
the hull when the
aircraft is on the water, and it helps reduce the suction of the water that
moat be overcome in
order to take off from the water.
Referring to Figure 51, the same view of the aireraft'a midaectian as in
Figure 50 is
2 5 shown, except that the outermost sections of the fuselage (300), as well
as the main skis ( 147).
the main wheel bath (148), and the fully revacted mounting srmaarrc ('n and
pontoon (23).
have been rezd~ transparent, and except for the fuselage (300) these
components are
repr~emed by broken lines ~ . - . ~. The lower line of the fuaeiage (300) is
shown by
a dotted line (....) where it is covered by the pontoon (?.3).
3 0 The main cenQal landing gear component as illusuued in Figure 51 is
comprised of one
or two (preferably two, as picwred, e.g.. in Figure 52) whaels (20) with
(preferably) poaunuic
tires, two skis ( 147), one or more shock absorbers or spring suspension
members ( 129), one or
more powered actuuors (hydraulic or air cylinders, or eletxric screw jacks, or
similar
apparatus) ( 141 ), and various connoting and supporting meaoba~a.
CA 02374576 2002-03-14
77316-13D
-44-
The main wheels (20) are rotatably mounted on a central ule assembly (Z10 in
Figure
54), to which is attached.a brake system (not shown). The ule assembly (210)
is connaxed via
a steering column (not shown) to a main gear steering control plate (220)
pivotally housed in a
swing-out main gear mounting cylinder (133), in a similar manner to the frotu
landing gear
assembly (see, Figures 44-49). The main gear mounting cylinder (133) is also
equipped with a
rearward~atending fin-likc mounting appendage (318) fuel to the main gear
mounting cylinder
( 133), to which a main gear connecting link ( 13'x, a main gear suspension
link ( 130) and
(preferably dual) shack absorbers/springs (129) can be pivotally attacZxd,
i.e., at pivm
connexions 135, 134, and 136 (Fig. 51), respectively. As in the forward
landing gear
component illustrated in Figures 44-49, the steering mechanism (not shown) for
the main central
landing gear wheels (20) will be conna~d to the steering condrol plate (220)
so that the
mahanism is engaged oNy when the swing-out main gear mounting cylinder (133)
approaches a
vertical (deployed) orientation with respect to the c~erline of the aircraft.
The main gear suspension link (130) is pivotally attxhed to the fuselage (300)
at a pivot
connection (t31). The shock absorbers/springs (129) are pivotally aaachcd to
the fuselage (300)
at a pivot connxcion ( 132). The main gear connecting link ( 137) as
illusuated is Figure 51 is a
tuning fork-shaped member which extends forward from its pivot connaxioo ( 135
on the
mounting appendage (318) to a main gear actuating link (138), where it is
pivotally atmch~ed at a
pivot comaxion ( 140). The main gear actuating link ( 138) is pivotally
aaac6ed to the fuselage
(300) at a pivot connexion (139). A main gear aexuator (141) is also aaached
tn the main gear
actuating link (138) at a pivot coonaxion (143) and is pivotally atrached at
its opposite end to
the fuselage (300) at a pivot connection (142).
It will be appreciated that acxuadon of the aforementioned series of linkages
causes the
swing-out main gear mounting cylinder (133) to rotate generally in the sagiaal
place of the
airaaR (similarly to the mounting cylinder (230) of the forward leading gear
component.
described syp~, thus deploying or retracting the main wheels (20). See. e.g.,
Figure 54,
which sbvwa the main wheels (20) and the associated main cemsal gear strucnuea
fully
deployed.
During extension sad retraction, the shock absorbers/springa (129) remain at
full length.
3 0 since they do na support any of the weight of the ainxaft. In touching
down foc a landing and
while operating on the ground (Figurts 54 and 5~, tlx main gear acatator (141)
remains at a
feed euea~ion, and the main gear acntating link ( 138) does not rotate, so
that the main gear
connecting link (137) holds its position, and the shock absorberslsprings
(129) compress and
decompress as the landing or tuiing load varies. The shock abaorbetslaprings
(129) operate in
3 5 the same manner to absorb landingltuiing toads during snow landings,
because the main skis
CA 02374576 2002-03-14
77316-13D
-45-
(147), as more fully described j~, are connated to the same main gear
connecting link (137).
This latter ~fa~t leads to,a further safety advantage of aircraft employing
the compound landing
gear disclosed herein: As can be seen with reference to Figures 50 and 51, the
main skier (147)
are the lowest part of the fuselage when in the fully retracted position:
however, even in the
reu~acced position, the arrangement of the landing gear connecting and
axuatang strucauet
described above permits forces applied to the sltis to be transmitted to the
shock
absorbers/springs (129). Therefore, for water landings but more importantly
for "wheeler-up"
landings on a hard surface (i.e., where the pilot either cannot or forger to
deploy landing gear),
the portion of the fuselage to come in first with the ground is advantageously
constructed to take more punishment than the rigid fuselage of conventional
aircraft. This
feature, accordingly, not only improves the safety of the aircraft from tIx
passengers' standpoint
but improves the likelihood that the aircraft will suffer minimal struxural
damage and will na
be totally lost after this type of landing.
The skis ( 147) of the main central landing gear component are mounted on the
main
gear conaating link ( 137) via forward and rear ski support arms ( 144 and
145) and main sld
connxting arms ( 149). Referring to Figures 52 and 53, where these eare more
ckuly
seen, the forward and rear ski support arms ( 144 and 145, respectively) are
pivotally attxhed to
the' main gear connaxing tinlc ( 137) in stepped recesses of the forward end
of the member.
These stepped recesses permit the ski support arena ( 144 and 145) to fold
flat against the base of
2 0 the train gear connxaag link ( 137), when the skier ( 147) are in a fully
retraxed paaiti~ as
shown in Figure 52. The forward ski support arms (144) are generally
triangular in shape. with
two pivotal connaxiont4 (213 and 214 in Figure 53) along the base to the main
gear connecting
link (137), and a biaxial pivot connexion (150) at the apex to the main slci
connecting arnti
( 149). As beu illustrated in Figure 53, each rear sti support arm ( 14~ is
generally rectangular
in shape (ref. Figure 5'~ and hat pivot connaxio~ to the main gear conneaiug
link (13'n at one
end and a pivotal connexion at the opposite end to a V.shaped double axle
member (238).
through which esch rear slci support arm ( 145) is coaneaed to a main sill
coooexing arm ( 149).
One arm of the V-shaped double axle member (238) is pivotally aaached to the
rear sri support
arm ( 145); the other arm of the V-shaped double axle member (238) extend:
through the main
3 0 slci connxting arm ( 149) and forms a pivot connection ( 150) about which
the main shi .
connecting arm ( 149) pivots. The relative angle of the arntt of the V-shaped
double axle
member (238) is such that the lower surfact of the sitis ( 147) are cauaod to
be horizontal to the
ground when the assembly is fully deployed and are caused to subataarially
match the angle of
the fuselage when the assembly is fully retraaed. The base of each main ski
connecting arm
3 5 ( 149) is pivotally attached to a sri ( 147) by pivot connexioat ( 152) to
flanges on the upper
CA 02374576 2002-03-14
77316-13D
-4b-
surface of the ski ( 147), as shown in Figure 53. Also shown in Figure 53 are
screw-driven ski
positioning ~ato'rs (215 and 216) for extending the skis (147) from their
fully retraced
position (see, Figure 52). The rear ski support arm actuator (215), which is
pivotally aaachCd
to the support arm as shown (239), pushes the rear ski.support arm (145) away
from the main
gear connecting link (137), which forces the skis (147) down and away from the
fuselage.
Extension of the forward, ski support arm acarator (216), pushes the upper
corner of the forward
ski support arm (144) away from the main gear connecting link (137), thereby
lowering the
biaxial pivot connatioa (150) and causing the position of the main ski
connoting arm (149).
and thus the main skis ( 147), to change by rotati~ about the pivot conna.Ki~
( 151 ) to the V-
shaped double axle member (238). It will be appreciated by reference to the
foregoing
description and the drawings (esp. Figures 51. 52, 53, 55, 57 and 58) that by
coordina~oed
extension and retraction of the ski positioning actuators (215 and 216), the
main skis (147) can
be raised and lowered through a wide range of positions relative to the
fuselage.
Although na critical to the invention, the various members comprising the maid
central
landing gear componem may be shaped and constructed to provide additi~al
flotati~ elemaus,
lending an additional feature to the multifunctional landing gear component.
As picwred in
Figure 52, for instance, the main ski comating arm ( 149), rather than being
fabricated as a
solid shaft ~ bar, has been shaped to fill the space bavveen the fully
ren~cxed skin (147) and the
flu-folded forward and rear ski support arms ( 144 and 145). Thus shaped, the
main ski
2 0 connecting arm ( 149) may be fabricated (without compromising its
stru~rral strength) to be
hollow, with the hollow compartment being watertight or filled with a buoyant
foam. The main
ski connecting .link ( 137) pictured in Figure 52 may likewise be fabricated
with hollow
compartments for buoyancy. The bay in the fuselage which houses the main
central landing
gear component prtfenbly will na be designed to be watertight, since this
would significantly
complicate the design and sharply raise construction costs. Accordingly, wbea
the aircraft is on
the water, the bay will be exposed to water. and any additional flotation
elements such as the
buoyant c~aectiag arm (149) will improve the seaworthiaesa of the aircraft.
Refatiag briefly to Figure 55, a cross-sectional aide elevation of the
midsection of an
aitcraft equipped with the prefaced main central landing gear component of
this invention is
3 0 shown. and the landing gear arc deployed for a snow landing.
To position the skis for operations on snow~overed surfaces, the car ski
suppocc arm
positioning actuuor (215,in Figure 53) is extended, which rotates the farvvard
cad rear ski
support arms ( 144 and 145) out from the main gear connecting link ( 137). The
ski support arms
( 144 and 145) position the main ski connecting arnos ( 149) so that the pivot
line ( 152) of the skis
3 5 ( 147) is near that of the main wheels (20). Adjustment of the level of
the skis using the forward
CA 02374576 2002-03-14
77316-13D
-47-
ski support arm positioning actuator (216 is Figure 53) permits configuration
of the main
central landing geu for proper balance of the aircraft on all types of snow-
covered surfs, in
particular during lift-off and touch-down. On totally snow covered surfaces it
is desirable to
position the slcia (147) below the wheels (20) to eliminate drag from snow
accumulating in front
of the wheels. (See, e.g., Figure 58.) During operation on surfaces of
intermittent snaw and
clear surface, the skis are advantageously positioned so that the bosoms of
the wheels (20)
extend slightly below the skis ( 147) and the aircraft consequently rides up
on the tires whore
there is no snow but rides on the skis (with the wheels providing minimum
drag) where the
snow covers the ground. (See, e.g., Figure 57.)
Referring again to Figures 54 and S5, it is importam to note that the main
txatral
landing gear component is positioned almost directly underneath the engines
(24 and 25). In a
twin~eagine aircraft, about half of the total weight of the aircraft is
acxounted for by the
engines. In conventional propeller aircraft, that load (i.e., the mans of the
engines) is out on the
wing strucaues; is aircraft as illustrated in Figures 54 and 55. the load is
mounted inboard.
diratly over tlx larding gear. In a hard landing, the energy of the mass of
the engines coming
into contact with the ground is dissipated through the landing gear: and in
conventional
propeller aircraft that energy is translated through the wings to the fuselage
and to the landing
. _ . g~~ pi,~g a Ivt of stress on the wing strucwre. W ith an arrangement of
engines and landing
gear as illustrated in Figures 54 and 55, the energy of the mass of the
engines at the velocity of
2 0 a hard (as opposed to a soft) landing is dissipated directly to the main
cenaal landing gear
component through the bosom of the fuselage, without putting those stresses on
the wings or
ocher strucnues of the fuselage. This is anocber feature which makes aircraft
according to this
invention more forgiving of commas pilot errors.
Figures 56. 58, 57, and 59 further illustrate the deployment sad operation of
a lateral
stabilizing gear compooea< of compound landing gear acacording to the present
invention,
comprising bilaterally situated stabilizing members, including integrated
wheel and pontoon
subcompooeaa. The drawings show a particularly preferred embodiment, wherein
the
stabilizing gear are integrated in pivotal mounting armatures also according
to the invention. It
will be recognized that less preferred embodiments of the stabilizing gear
component may
3 0 alternatively be mounted under the wings ~ extended from the fuselage on
separate supporting
members. Employing the mounting armatures gives the stabilizing gear the added
advantage of
being fully retractable. as well as being coordinated with the paaition of the
propellers.
Figures 56'59 present similar frontal elevations of an aircraft according to
the invention.
showing the relative orientuion of the main central landing gear component and
the lateral
3 5 stabilizing gear component, in each of four funding configurations.
Previously discussed
CA 02374576 2002-03-14
77316-13D
.4g_
elements such as the propellers (8, 9), engines (24), belts, flaps (72),
ailerons (10, 11). main
skis (14'n, nnain wtiecls (20), etc. are provided for reference, however many
previously
discussed structures have been omitted from these views for the sake of
clarity.
As illustrated in the embodiment of Figure 56, the pontoons (22 and 23) are
integrally
mounted on, and form the lower segment of, the pivotal mounting armatures (6
and 7,
respectively). Thus, rotation of the armatures away from or into the fuselage
(300) by means of
the multilink actuating struts (280 and 281) deploys or retracts the pontoons
(22 and 23).
Stabilizing wheels (18 and 19) are aaacbed to the pontoons (22 and 23) by
wheel
mounts of course permitting free rotation of the stabilizing wheels. The wheel
mounts may be
fixed or (preferably) retractable. In the embodiment illustrated, the pontoons
are fabricated with
recesses into which the stabilizing wheels ( 18 and 19) can be t~evxxed.
Exunsion or ret~ction
of the stabilizing wheels (18 and 19) may be performed by nay suitable means
(e.g., separate
powered actuators); however, preferably the stabilizing wheels (18 and 19) are
mounted, as
shown here, so as to automatically extend or retract according to the rotation
of the pivoting
mounting atmacures (6 and 7), which is effected by means of statboard and port
stabilizer
actuating links ( 168 and 169, respectively) fixedly attached not one end to
the respative
stuboud and port muldlink actuating struts (280, 281), std pivotally attached
at the other end
to pivotal wheel mounts to which the stabilizing wheels ( 18 sad 19) are
rotatably mourned. The
stabilizer actuaaag links (168 and 169) are fixedly attached to the final
(outboard-most) lilt of
the 4-link series of each multilink actuating strut (280 and 281; ref.
description, ~, so that
at intermediate extension of the multilink actuating struts (280 and 281),
reaaaabie wheel
mounts are forced down, swinging the stabilizer wheels (18 and 19) irno a
deployed position.
(See. Figures 56, 58, 57.) When the 4-link series of the tmiltilink acwating
struts are at full
extension (Figure 59) or when the oucboud 4-bar linkage is collapsed (i.e.,
when the mounting
armadua ue retracxod to the fuselage), the angle of the final link of the
multilink acritatiag
struts (280 sad 281) c6aoga, and the stabilizer acaracing lidca (168 and 169)
are pulled
upwards, causing the stabilizing wheels ( 18 and 19) to swing back iron their
respoaive recesses
in the pontoons (22 and 23).
The stabilizer wheels are preferably non-steerabk sad are on caster mounts, so
that they
3 0 swivel to roll in any diradoa thu the aircraft takes, as soon as they are
in c~tacx with the
ground.
Each of the subcomponerns of the main central landing geu sad the lateral
stabilizing
geu (i.e., main wheels, stabilizer wheel, main skis, pontoons) moat be mounted
in the aircraft
so that when fully deployed, the center or pivot axis of the subcoatponern
(e.g., hub of the
wheel or pivot mourn of the ski) is positioned at a point 8-13°,
preferably 10-11°. aft of the
CA 02374576 2002-03-14
77316-13D
~9-
center of gravity of the level aircraft. Furthermore, when the lateral pontoon
members are
deployed (22-and 23 in Figure 59). the exposed underside of the fuselage (see.
dotted line in
Figure 51) must form a step 8-13°, preferably 10-11 °, aft of
the center of gravity of the level
aircraft. 8y "level aircraft" is meant an aircraft where the fuselage is level
fore-and-aft with
respect to level ground, i.e., the longitudinal axis of the aircraft is pualkl
to the ground. A
plumb line from the center of gravity of a level aircraft will be perpeadiculu
to the centerline:
and the center of exh aft landing geu subcomponent, when fully deployed, must
be fu enough
aft of the center of gravity so that a first line, extending from the of the
deployed landing
geu subcomponent (e.g., the hub of the main or stabilizing wheel), parallel to
the longitudinal
axis of the aircraft that includes the center of gravity, to interact the
transverse axis of the
aircraft that includes the center of gravity, and a second line that is a
plumb line from that point
of iaterseccion of the first line and the transverse axis will form as angle
of &13° and
preferably 10-11 °. If the landing geu design caused ctx landing gear
to be deployed focwud of
the first line, the aircraft would be prone to rotating bah on its tail and
never allowing the noac
geu to touch down. If the landing geu design caused the landing gear to be
deployed too far
aft of the first line, the rotational force coming down on the nose gear
during landing wouk be
too great for the forwud landing geu (and possibly the nose section of the
fuselage) to handle
. . without damage. If a step in the fuselage is placed too far back, the drag
of the water on the
fuxlage will be too great to overcome, and the aircraft will not be able to
take off from water.
Figures 60 and 6I diagram two passibk stewing mechanisms for the statable
forward
landing geu and the steerabk main central landing gear. In the mechanism of
Figure 60, the
main central landing gear and the forward (nose) landing gear ate stared by
the same
mechanism, with the nox gear additionally independently sseerabk by the ruddy
pedals (229; R
- right, L ~ left). In Figure 61, the steering mechanisms for the nose gear
and the main central
gear are indThe coordinated mechanism of Figure 60 is preferred.
Referring to Figure 60, cable-and-pulley conneaiom are made betwan a steering
xtuator plain (223) and the forwud geu steering contml pf~e (193: see, also.
193 in Fig. 49)
and the main cxntral geu steering control plate (220; see. also. 220 in Fg.
54). The steering
actuator plate (223) is driven by the steering control motor (224), which is
connected to the
3 0 acatacot plate (223) through a geu box (225). An override hard crank
steering control (226) is
preferably provided in the event that the stewing control motor (224) biomes
inoperative. The
positioning of the steering actuator plate (223) is translated to the main
cxntral landing gear via
cables (221 ) connecting to the main geu steering conaol plate (223). Pulleys
(222) ue
provided to guide these cables (221 ). The positioning of the steering
acxuator place (223) is
3 5 translated to the forwud landing geu via cables (227) connecting to the
forwud gear steering
CA 02374576 2002-03-14
77316-13D
-50-
control plate (193). Pulleys (222 and 235) are provided to guide the cable
(227) appropriately.
The forward-gear steering cables (227) also coop around pulleys (237)
rotatably feed to the
rudder pedal connecting bu (240) in a slack-giving/slack-taking arrangen0ent,
so that
movements of the rudder pedal connecting bu (240) are also translated to the
forward gear
staring control plate ( 193).
Referring to Figure 61, a similu arrangement of cables and pulleys to the
xheme of
Figure 60 is shown, except the forwud gear steering cables (227) do not
connect with the
steering actuator plate (223), and therefore the forward (nose) landing geu
and main central
landing geu steering controls ue independent.
With the steering mechanism design shown in Figure 61, the pilot adjusts the
main
central landing geu steering angle by operating the steering control motor
(224) (or the override
handwixel (22b)) to compensate for or cancel the "crab" angle to which the
aircraft is turned at
takeoff or landing to compensate for cross-wind conditions, thus matching the
angle of the
landing geu to the direction of the rummy. The pilot also sets the same angle
into the hose
geu using the rudder pedals (229). Witb the steering mechanism design s6awm in
Figure 60,
however. the pilot sets both the main central landing geu and nose geu angle
with the steering
control motor (224) (or haadwhxl (226)). The rudder pedals (229) are used oNy
to make fine
. . ~j~~a~ to the nose wheel with respect to the angle already set by
positioning of the main
central landing geu. Pilots will recognize that the incorporation of steerabk
forwud and main
2 0 central landing geu virtually eliminates the erects-wind limitation
inherent is aircraft with
conventional landing geu designs, espxialiy where this fore and aft steersble
landing gear
feature is combiru~d in an aircraft having the compound wing structure,
dexribod previously,
which can be acxivated to dramatically Iower the stall speed of the aircraft.
A 1/5 scale model of an aircraft according to the invention was coattrucced
out of balsa
wood with a styrofoam-filled core and a fiberglass shell. The model had the
fuselage and wing
configuracioo of an ai~'t as illustrated in Figure 1. and it was powered by
two 2.2-
horsepower. single-cylinder model airplane engines and props, mauated ~ the
coda of
armatwes (see, e.g., items 6 and 7 of Fig. 1) raised above the wings. The
nu~del was suitable
3 0 for studying general flight chuacceristics on takeoff, landing and low
speed cruising flight.
Remae-coruroiled flight of the model indicated acxxeptabk fiigtu petfonmsace
(including rudder
effeaivetuss at low speed) and good correlad~ to predicted paformana.
Two computer modeling programs were written, one to predict performatrce std
une to
predict stability of an aircraft based on input of data describing the size,
weight, power and
3 5 configuruion of componetus. The programs were tested and verified using
published data from
CA 02374576 2002-03-14
77316-13D
-51-
extensive wind tunnel studies conduced by the U. S. Air Force. A computes
model of an
aircraft accordia~to the invention was then compared against a computer model
of a
"conventional" aircraft pauerned after several known production twin~agine or
amphibious
aircraft. The computer comparisons predicxed that the configuration of
aircraft according to the
invention having inboard-mounted engines reduced the power requirements by as
much as 20~
over those of a conventional twin-engine aircraft. Additionally, aircraft
according to the
invention having the engine and drive system and the extendable wing system
described herein
had a single engine climb rate 120% higher than that of a conventional twin-
engine aircraft
model. In comparison to a conventional amphibious aircraft, presuming a single
engirx
mounted on a pylon above the fuselage, the computer model aircraft according
to this invention
had a maximum level cruise speed of 160 that of the conventional model.
Wind tunnel tests of small models of aircraft as described herein in various
configurations (e.g., wings retracted, wings extended, cetmal landing gear
deployed) were
conducted and showed favorable aerodynamic characteristics in all
configurations. In patticulu,
desirable non-turbulent airtlaw was observed across the vertical and
horizontal conQOl surfaces
of the tail section when the main wing section was placed in and tear the
stalled attitude.
Multi-purpose aircraft having a range of performance capabilities may be
produced
according to tl~ foregoing description using conventional materials and well
known aircraft
construction techniques. The major savca>tal components of prefaced aircraft
according to this
2 0 invention are shown in Figure 62, which is an exploded perspative view of
as aircraft similar
to the embodiment illustrated in Figure 1. Moat of the structural members
picatred in Figure 62
may be readily and preferably fabricated out of aluminum stock. e.g., by high-
pt~essure water jet
cutting. Most of the strucaues illustrated in Figure 62 have already been
described and will not
be further described beet. The reference numerals employed here correspond to
the descriptions
2 5 ~yp~. With rapes to the primary structure of the fuselage, Figure 62
illustrates the modular
design of the aircraft: The primary fuselage strvcntrr is formed by bolting a
main fuselage
saxion (300) including a tail section (310) etd-to-end with a forward cabin
module (233) and.
optionally, with an intermediate cabin extension module (234). An upper
cockpit assembly (3)
and an upper cabin extension assembly (2) are attxhed to the forward sations
of the fuselage
3 0 primary structure to provide a continuous cabin enclosure. As illustrated
in Figure 4, the
intermediate cabin extension module (234) and associated upper cabin assembly
(2) tray be
omitted during cocutruction of the aircraft to produce a shorter, lighter
aircraft. Alternatively.
for a larger enclosed cabin space, wide-body upper cockpit and upper cabin
extension
assemblies (231 and 232, respectively) may be substituted during construction
for the standard
3 5 upper cockpit std cabin extension assemblies (3 and 2, respectively). A
wide-body version of
CA 02374576 2002-03-14
77316-13D
-52-
the aircraft, illustrated in plan in Figure 63, results. Thus, several
different types of aircraft
may be asseZnbled.in the sane; plant, without redesign of the primary
strucaual components.
From the foregoing description, many different embodiments of aircraft
i~orporating
innovative feature uxording to this invention will be possible. All such
embodies,
including obvious variuioas of the particularly preferred designs disclosed
herein. are intended
to be within the scope of tlus invention, as defined by the claims thu follow.
