Note: Descriptions are shown in the official language in which they were submitted.
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:~OM ~EEilLEf~ Pfl~)lTT (111~ 04 . ~ g6 I~lu. 1 ~FIEIF ~15
BI~ J 105
WINGED RAM PRF,:~SUF~ WATERCRAF
~KC}~OI~Nl~ F THE I~VE~TIOI~
Th~ present inven~ioll relates to a ram-pressure wing, g~,ound effec~
watercraf~ which floats on water at zero ~peed or ~rery slowl speeds but
~hîch lifts out of the water with increasing speed and glidel above the
surface of th~ wat~r on a dynarnically gsner~ted and mai~tained ai~
10 cushion~ as a ~round effect de~ice al:ld will ~emain, as ~ as lift is
conce~ed~ within thi~ region of g~ound e~fect.
With increasing t;he li~t and concurrent reduction of re~ist~nce and
dra as one win~ approache~ ~ound, it is Icnown to be tLeuretic~lly
5 ~easible to obtain ~ er2 ft in so-called win~-in-~gxound effect c~n~iguration
or "wi~" for shor~, and to use ram pressure under the wi~g as a lift
produci~ ~ut ~round effect de~ic~ a~ ~utlined above. It is a ~equileme~t
~o~ such ~n effec~ to tak~ place that the ~1ide number is in fa~ improved.
This mea~s a hi~hly e~fective ~rans~rmation o~ thP dyna~ic r~ pressu~
20 into a s~atic e~ces~ pre~sure is Iequi~d. For this to o~tain, ohe ~eeds ~n
opeI~in~ at the fro~t a~d hi~hly eff~ctiYe la~eral and ~ar ~nd se~li~ of the
wing ~o pex~nit developmen~ of ram and ~ynan~ic pressllre in a plenum
undern~dth th~ cr~, (i.e. be~we~ h~ ~ra~'~ body taken ~s al wholc; and
the wate~ su~ace). A ~lraft ~onceived irl such a manner shoul~ pe~ , of
25 course~ a~ ~dvanta~ s ~vnfiguratic~n ~.s a ship o~ boat,'.par~i~ularly
owing tO the fa~t ~h~t ~h~ wat~r sur~ac~ is 3~eneral1y a planc s~fa~e. ~ince
the cra~t i~ ~uppo~ed tc~ be airbo~ne, it mu~E b~ ~ery li~ht, ~hil~ on th~
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F R O M B E E H L E R P l~ u l T T ~ 3 4 ~ 0 I ~ ' g l ~ 7 ,~I O . I P ~ q E ~
~ ~3 ~ 9 ~ 8 0 '
other hand, it mu8~ resist high loads through water impact~ ~articularly
~lu~in~ the ~ake~ d landin~ phase~. ~
The ~ater resistance to be overcome du~in~ ~ake-o~f i~ ~bout 2 to
5 3 times as la~ge as th~ air ~sistan~e to be overc~me when ~he Icraft moves
in an airbomo mode clo~e to the ~rouncl This is ~ue to the faft that water
is 800 tirn~s as dense as air~ Con~equently, the propulsion power
requireme~t is ~ominated by the requirements for tal~e-off. The
prop~lsion needed on take-of~, on the other hand hand, is primarily
10 determined by the weight of ~he c~aft at the time o~ take-off, There-fore
wi~h the ~ed~c~ion in weight owin~ to filel consumption or lo~ additional
loads the craft will in fact e~cpe~ience dyllamic f~ee flight, ~i.ei well above
the ~round effect), but still the grvund effect i~ effective a~ jlon~ as the
craft is ~ot higher ~o that at leasl; o~e third of the wing spaI~ and for the
I S entire win~ depth experiences ~round ~ffect. (: onsequently, lhls kind boat,particularly if actu~ controllable about 3 axes, could ju~ti~lably be
termed an aircraft; ~ specti~e of the label attached to such ~ craft, free-
flight oper~ting ~nodes w~uld re~uire, for ex~mple, ~rplane I el; i~ would
require customa~y ~ircra~t p~opulsion ~ s aI~d, not least, ~hould it be
20 tçrmed an "aircra~", îts opçration woul~ xequire ai~ pilot clerti~lcation.
All thi~ is, of course, a decisive cost ~ac~or and not just anybody will be
allowed to op~at~ ~uc~ a cr~
.
Another kind of vessel is ~nown which comes under ~he name of
2 5 tandem air~foil b~at, wh~rcin the~ is a ~round-depeIldent di~t~bu~ion of
li~ o~ account of ~ ta~deln win~ss being a~anged on~ behi~d ~he other~
This a~angement, ~ effe~t~ is supposed to ~ake su~ that ¦~he distance
,
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R O M ~ E E H L E, :I V I T T ( 11 Cl 1~ ) 0 4 . ~ I a g~ E 4 ~
¦1 E5IS J 105
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f~m ground remams slight. However, tbis kind o~ Yesse1 andl cra~t has ~
very limited maneuverability because ~or example, t~ey cannol bank while
flying in a curve ~o~ use elevatiol1al changes under utilizatiol, of kinetic
ener~y, for example, to jump over obstacl~s. Owin~ to the In~ssing
5 elevational corltrolJ it is IlOt pos~iible to guid~ the craft back lowards a
ground near-flight l,evel, in case, for e~ample, the elevation lo~ the craft
happens to increase as a resul~ of, for exa~ple, air flow developments or
oper~tor erro$s. This is so ~ecause once g~und effect is no longer
ef~ective, stability of movement is impaired and the craft is nv longer
10 ~dequately maneuve~able.. ~ ;
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: ~ It is a feature of the prese~ invention to improve r~m pressure
wing-grolmd effec~ wa~e~ crafts towards avoidin~ free-fli~h~ conditions
and its comn~ensurate disadvantages, by employing a rar~-wing boat
co~ guration arld co~struction wherein ~he resistanc~ on ~Ibtaining ~n
0 ele~atioll in exces~ ~f one third 4f the win~ span i~ ~ar~er th~n ~he water
resist~n~ to be ove~o~e durin~ take~o~, so that free ~light ls inherently
avoi~ed without ~he aid of a~ificia1 means such as elevation~dependent
a~tvm~ co~trol o~poYV~r reduction
It i8 therefore an object of the p~esellt ~vention ~o pr~vide a craft
~5 and wing ~on~1~ur~ n, as well as ~ sealin~ ~truetu~e fo~1the plenum
ILndemeath $h~ ~ra~t, which a~oids ae~vdynamic free-llight siTply th~ough
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f R O lt~ E E E H L E R P R ~ T ~ M O ~i ~ 0 4 . ~ 1 0 a ~ , I P ~ E S / 1 ~;
increasin~ the resista~ce over the resistance found on také-o~ when the
cra~ exceeds cer~ain eleva~io~lal values.
The ~biect and feature are obtained in a ver~ small ~p~n width and
great wing depth w~icll are reflected in a sid~ satio ~nd whichlwill in fact
S cause an increase in i~duced re~istance wheneYer the cra~t's al~itude
incr~ases. Th~ particular features involved conccrll the sealing of the ram
pressllr~ developin~ plenum; the t~ailin~ ed~e of the win~g is ~qunded by a
yieldin~ p-like s~cirt configuratioll, and the sides of the ple I um, e 8- at
the wing tips, is ~ounded by hin~edly yielding blad~s that may pivot o~
10 hori~ontal transYerse axes. C)~ the other hand, the same ~eatures actually
red~ee resistance ontake-o~f.
Th~ t is thu~ controllabl& throu~h control of the lat~ral and rear
sealin~ 4f the pressure plen~m beneath the cra~t, particul~rl~ the win~s~
such th~n on th~ o~e hand, hi~h li~t and low r~sistance obtain j~uring takQ-
15 off but the lif~ is reduced a~d resistance as ~he cra~t movels above ~hewater su~ace are such ~hat in fact the cra* will never ~et hi~helr than about
on~ third of ~e spall above ground in a self-cc)lTecting manne~ lf the craf~
were to rise fur~er, the ple~um would just lose ef~ectiYeneSS, t~e rear ski~t
and lateral bla~es no longer containin~ tlne pressuri~ed air3 I d the c~af~
20 wouldo~ceagain descend.
On order the l~a~e rear water speed as ~mall as possibte, ~e wing~
should be as light as possibl~, th~ wing~, of course~ OCCUpyi~ the lar~est
volume in t~e const~ctioIl, all th~ w~ile the co~truction ~aYi~ to be
~lrm ~d resista~ a~inst lo~d from w~ter impacts. Tberefq~, the rear
2 5 stmcture, parti~ula~y when th~ ~ra~t ~s a whole is sma~l? is p¦efe~ably not
of t~e u~ual r~b spar con~1guration no~ covered ~vith as stiff ~ nlaterial as
skin, but is, r~her, re~dered ~lastic throu~gh a flexible skin Icove~ing. In
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R 011 e E E H L E R P fJ U I T T ~ ~1 b ~J ) 0 4, ~ ~ " ~3 1 2~g ~ 3 ~ P ~J r7 E ~
I BIS / 105
order to obt~in hi~h li~t, one clevia~es from p~oposals in ~;erman Patent 25
.: 47 945 which provides a on~-~ided sail; and in the present c Ise a doubLe
coverage is providcd in o~der to obtain optimum p~ofile confi~uration.
O~e-sided skin coverage, of cours~, can~es with it the risk thaf water can
5 enter the win~ ~ecause the WiIlg, prior and dur~n~ take-off naturally rests
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on the water, and the ensuin~ entrance of water m~y inereas~ weight
and could, if not Avoided, cause an uncontrolled and par~;icularly an
unsymmet~cal shift in the center of ~ravity. On the other hand7, in the case
o~ a double coveringJ only dama~e can ~ive rise to ingress of ~ate~. In ~he
10 static displacemen~ state, the rear or ~railin~ ed~se of th~ wing has ~o be
der the watel's su~ace prior to talce-o~ and over the entire 1~n~th o~ ~he
wing, so th~ on lift of~ t~ailin~ edge sealing of the plenuL~ is in fact
gua~anteed.
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DE~I~I~OF ~ R~WI~GS
While the specifieation concludes with claims llparti~ularly
poi~tin~ out and distinctly c1aiming the subject matter whi~ isl ~ga~ded as
the inventio~, it i~ believed that the invention~ the objçcts and features of
20 the invention and f~r~sr objects, ~eatures and ad~Janta~es the'feo~ will b~
better understood f~om th~ followin dese~ipti4n taken in con~ection with
the accompanyin~ ~awin,~s in which: li
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Fi~. 1 is ~ p~rspec~ive ove~view of a cra~t in ~ çc Irdance with
2 5 the pr~ferred embodin~ent of the pre~ent inver~tion;
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FROM EEEHLEI~ P~l~)ITT ~11tllJ>~q.~ tl~. I Pf/ci~ 7/1~
s 1 1~5
Figur~ ~ îllustratcs on an ~nlar ed sc~le and in ~ somewhat
schematic b~sis detail~ of ~he const~uction of a ~in~; ~
~ !
Fi~ure 3 is a cross section through the wirlg illustrating,
5parti~ularly, a rear or trailin~ edge and a skirt in a conditibn of static
displacement;
~ gure 4 is a vi~w si~Pilar to Figure 3 but showing take-off and
I~ndin$ pha~es with displaced trailing ed~e ski~t;
., 10
Figure S illustlates ~he fli~ht col~dition close to ~roul nd;
Pi~u~e 6 illus~rates the ~aft sho~n in Fi,~. 1 withl a particular
confi~ tion of l~te~al sealiIlg;
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Fi~ure 7 illustrates the displacemen~ condition sho~ Fi~g. 6
but in a ~ront view;
!l
Fi~ure 8 illustrates the flight co~dition when the ~rai~t is near
2 0 ~e water surface~ ¦
Fi~ur~ 9 ~llustrates the ~ont view of the operalio~al phase
depicted in Fi~ure 8; and
2 5Fi~ajure :iO show~ a ~ont ~iew of the craf~ ~ a whlo~ showill~
p~rticularly t}~e seali~ ef~ect o~ ~nking flight w~en a cu~ve is negotiated.
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R O 11 B E E H L E R P R V ~ T T ~ M ~ IJ ~ ~i 4 . 0 1 . ~ 3 1 ~18 ~ . I P h ~i E s~ 5
r~ ~ 315 1 1ûS
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Prvceedin~ now to ~ detailed desc~iption of th~ drawil gs, Fig. 1
illust~ates a cra~t wi :h a body 20, a shrouded propelle~ unit 21l on top of
`the fusela~ge 20 as a propulsion urlit, and elevatio~al con~rol 2~ in the rear
or aft poltion of th~ craft. Of cAtical i~portance is a wing 1 ~Ivith a nose
11 bein~ of a profile-definin~ solid structure, for example, wood
synthetic or even rnetal slcin. Ill addition, Fig. 1 shows flot~tion bodies g
and 8aS and outer, upstanding win~lets 10 and 10a, rearwardly pivotable
and defle~table blades 12 and 12~ are pi~otal~y mounted to the flotation
bodies 8 a~d 8a respectively. Suppo~ structures 3 and 6; and la ~kirt 5 o~
flexible con~lguratio~ will be dcse~bed more fully below.
Fi~ure ~ shows in ~re~ter detail the structure for the ~ ing nose 1,
and there is ~ skin cover 4 in the central and rear pare of ~hle wi~.The
trailing ed~e is ~ormed at a ten~ioned cable 2 in ~he case of a ~exible skin
cov~r 4, Y hile i~ case the trailillg win~ ed~e is defined by a si~id or sti~
~e~r edge bar, the skin cover of the win~ is ~Iso stif~. For supporting the
tr~iIing e~e durin~ take-o~ and landing, particularly wherl jthe trailing
ed~e is sub~e~d in water and ther~fore subiected to impac~s by the
~ate~, sti~ support bar~ 3 are provided and extend fro~ the Ibody of ~he
2 0 craft at an angle towards the rear. T~ese bal~s ~r sp~rs havel to a~oid
bulgin~ of the trailing ed~e which is particul~rly possible i~ the traili~g
- edge is con~l~ured a~ a cable. Thi~ buIgin~ ma~ be the resulI of head or
r~m pressure in the plenum undemeath the Willg ~or~ ura$~on; but the
rear ed~,e has to re~ain straight iIl o~der to maintain the prelssure in the
~5 plenum~ i.e, in o~er to prevent cxcessiv~ le~ e f~om underneath tho
c~ft's body.
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'R4M BEEHLEI~ P~IUITT ~.llON ~4, ~ g~ Ji. I F~ 5'i~
~ 105
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A flexible skirt 5 is provided along ~he trailin~ edge 2 w~ch skirt, Ln
t~e cas~ of st~ic condition, simply dips into the water surface as shown in
Figure ~. This sk~ is o:f a one-sided con~lgur~tion so that ~ater cannot
enter into cavities, as ~rould otherwise be possible. The flexiible skirt is
5 supported and held by me~ns of resilient spars ~, thus avoidilhg vibration
during flight, On the o~er hand, th~ skir~ 5, owing to thl par~icular
stiffness and resilience of th~ spars ~, can yield to mo~ing wal er; ~nd this
is not only pe~mitted but desirable. The sprin~ sti~fness of ~ spars 6 is
d~termilled such th~t during fast moveme~t in and on water, ~~r ~xampl~,
10 durin~ take-of~ the skirt will sli~ on th~ water surface 7 wl ile ~ippin~
o~ly s1i~htly in~o the water at take off and this sig~ can~1y r~duces dra~g
and resistance durin~, talce-of~. Th}s is ne~essary in order to keep ~e
power requirement in the take-off phase as low as possib1e, ~nd to ~v~id
the above-me~tioned ~ree~fli~he; the craft is ~hus positively prevented
15 ~om becom~n~ and being te}med ~ ai~af~
Pi~u~ 3 sho~s the ~ki~t 5 ~s well a~ ~he ~lient and sprin~g-like
support bar ~ the static displa~em~nt state while Fi~. 4, ln the othcr
h~d, shvw~ on talce-o~ ~ut al~o during landin~, how the skirt ~i has shi~ed
O into an orientatioll p~r~llel to the w~ter surf~ce 7.
Pi u~e 5 zlow illustrates a fli~ht ~ondi~io~ close to the ~ater sur~ca
7 Yvhere ~e resilient sl~irt ~ seals the plenum $~wards the re~r.l ~n all ~ese
operatin~ conditi~ns, loads on the }oad-bearin~ ture i9 alvoid~d, a~d
particul~rl~ th~ case of contact with water and waves, the fi~ure shows
2 5 ~e r~ady yieldability of cn~ic~1 components which iII additio . to b~in~ a
weight-reducin~ fac~or, e~hances ~a~ty
F R t) ~1 E E E H L ~ R P FI U I T T ~ 1~ 0 ~ l 4 . 1~ 1 2 ,~10 . I p Fl ~ F 1
IS f 105
11l order to ~bt~i~ a low propulsion power input during take-of~ an~
close to ~round flight~ ~i.e. in order to asvOid f~ee-fli~ht in la dyn~mic
sense,) ~?Se pleIlum InsUSt also b~ laterally seal~d, but such that als the craft's
elevation inc~ease~ i~ a~titude above wate~, the resista~ce Idrastically
5 increas~s so that the era~t will return to near-~round conditi Ins. This is
obtained by providin~g for a slowly inc~easin~ indllced resist~nce with a
chose~ extremely low side ratio of span-wing-to-wi~ are~.l This ~tio
exeeeds the air resist~ce of the elltire craft and thus ~imply ~reYents ~he
cra~'s b~in~ able to reach an altitu~e a~o~ abou~ on~ third of the ~rin~-
1 0 span.
The ~levelopment of a dynamic ~ir cushion req~,lires, accordingly~
sealin~ of t'~e plenuln not only in the rear but also la~erally ~sl lon~ ~s the
~raft moves ,^lose to the water's surface up to ~ particular eleYal ional ~evel.15 This lateral seali~ olves, pa~icul~rly, th~ wing-~ips which ar~, fo~
reasons of safety, con~l~ured as sllppo~ g flotation boclies g a~d 8a. In
order ta obtain a ~tatic floating condition e~ireIl when the cFaf~ is ~ully
loaded, a cer~in buoyancy displacemell~ is inevitable, which means tha~ the
- fron~ of the cra~'s bod~ for example, as well as the f~otation ~odi~s 8 and
2 0 8a, ~as to be immersed to somQ exten~ in water. This i~;nmersioln shQuld be
kept as low a5 possible in orde~ to minimi~e the gap betwee~ tr~iling edge
of the wing and the w~ter sur~ac~ when thc cra~t moves close to the
~round. (~ he othcr hand h~wever, the ~e~ista~ee on talce-olf~ has to ~e
kept as small as possible and, o~ coursç, if ~ ra~ a~ a wbl le dips too
2 ~ deeply in~o the water, ~t resistallce i~ ineYit;abl~ hi~h.
-~ Ther~ore, ~he penetra~ion of elements provided alon~g the ~railin~
ed~e is t~ b~ kept as small as possi~le, pa~ ularly dllri~ ake-of~ and
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ROM 13EEHLER PhlJlTT ~Ml3N)el4~0l .912~,~ ;y3~ ~3~ ~ ' Pfll3E 1!/15
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j B1S 1 105
landillg. In o~der to ~neet this requiremen~, the outer flotation blodies 8 and
8a a~ provided with the hinged vertical blades 12 and 12a configured as
follows. During floating, the blades are late~lly deflected and ~est on the
water, i.e. tb~y do not dip into the wat0r and therefore do not Increase the
- S water ~esistance on slow speedx, but as the craft li~ somewhai, the blades
1~ and 12a, p~ticularly in the sliding mode, will piv~t do~n and thus
laterally seal the ~e~r part of the ple~um underneath the planels body and
fuselage. The blades wiil pi~ot more ~r less into a vertical pOSitlO:Il as the
cr~ft inc~e~ses in altitude~ ~ut once th& blade~ h~ng ~traight down, further
increase in th~ c~f~'s al-~itude ope~s a ~ap betweel~ the blades alld the water
surface. On the othe~ hand, ~e yieldin~ I han~in~ suspensio~ of the blades
ass~res th~t as water hits the blade ~ro~ one side~ ~or examp~e owin~ ~o
w~YeS, no acceleration loads a~d ~om~ts occur"
., l
l S The i~ventive arrangement provi~es that in cas~ o~ a ti~ht ban~cing
a~d cuNi~J the air-cushioll, p~r~icularly on Ihe side o~ the li~ted wing, is
~ot imp~ired, I~ order to p~rmlt a bankin~ position, tra~svlr~e ~dder~
a~ provided at the wing as a l~md o~ ~Ipr~gh~ wi~ t. The l¢f~ctiYeness
~ear ~rou~d is limited ~uch ~at, as a wing por~ion comes vl ~y close to
the ~ound or ~ç wat~r s~rface, that wing portio~ will cause a
compression of ~ aix cushion u~derneath, ~nd that comprel sion would
of course a~ ~gai~st ban}ci~, but in th~ ~,se of ~ralnsverse rudde~s whieh
~e too la~7 would have ~o be compensated t~r~u~h low-we;~l;, arti~lciat
resistance, and so ~orth, MoreoYer, aæ the vther win~-end par~ 1if~s,
cushiion support will b~ los~ so that the ~tal lif~ is reduced, and tha~ of
~ou~se csuld lead to ~o~ t with water, which ~ain, couid I vrmally b~
- a~oided thro~h elevational cont~ol. Al1 this again provldes c~?nditio~s for
0
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R011 ~3EEHLER P~IIJITT ~11CIMJ04.~ 13 ,il~, I PFlli 1~/15
2 ~ fi5 ~ ~ !
operating the cra~t which would caus~ it to bs termed ~ a~rcra~, and the
- operator ~ould as a result have to meet pilo~ re4uirements, the cra~t could
o lo~er be;n~ termed a boat. The structure that will be des~ribed next
avoids these problems.
Fi~ure 6 illustratcs ~he cffect of lateral sealing in accoldance with
the invention. ~t includ~s, as stated~ the flotation body 8, a s lep 9~ outer
upstanding winglct 10, trans~erse ~dder 11~ as weJl as blas~le 12 which
can be rearwardly lifted and is itsel~ prwided with a securel~ co~mected
~uoyaIlcy body 13, the blade is ~reely pivotable through a F~in 14 on a
horizontal tr~ns~e~sely e7~tending axis Thes~ parts are in ~act $1ecured in a
~i~id fashion to the ~vin~ 15. The illustr~tion of Fig ~ i~ that ff t~e staiic
displacement wbe~e th~ flatation body 8 is submerg~d in waterjup u~til the
rear or tr~ilin~ ed~e lifts o~. Fi~,ure 7 il1ustrates this dl'splacemen~
condit~on in f~ont view as stated abov~.
. ~
~ ow as ~r as operation is conce~ned, Fi~u~e ~ illustr~te~ the near
- ground nloving where ~h~ blade 12 is pivoted down untill reachin~ a
certain stap3 owin to ~e gravity, so ~hat the pte~um is and remaitls sealed
2 O agaiIlst the outside. In cas~ of conta~ with waterl for example thro~h a
wa~e, t~e fl~atin~ body 13 sisnpl~ provides ~ yieldin$ Qf ~he bfade, it so to
~peal$ ~oes with the waves, thus a~oidtn~ undue loads on ~he s~ructure.
Fi~ure ~ illus~rate~ ~ same situa~ion but in front ~iew.
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P;~. 10 now illuitr~tes th~ oYerall s~alin~ e~fect of t~e i~v~ntive
structure thro~h ~ one sido blade Gonff~u~ation when th 1' cra~t ba~s
and flies in ~ cur~e. A particul~r eoll~agwra~ion h~vin~ ~re~Lt a~Yanta~e
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~OM E~EEHLE~ P1JITT ~Mt~ 8, 14 NO. I PFl1~E 13/I:~
2 ~ IS I 105
~esults frum the comblnation of the two killds of sealing.as shol~vn, namely
the y~elding ~ the trailin~ edge skirt 5 ~nd the pivota~le bla!des 12 and
12a. The cont~ol of ~h~ skirt 5 i~ dependençe upon ~he blade 12~12a can be
Inade p~ssible through mechallical lilllcage or through active control
element becausc the blade which non:n~lly hangs down ~reely lan be used
~s distance or ~levational transducer. Th~ control of the skir~ or the
blades can be carried out manua~ly throu~h the boat operato~.
.,
The pa~icula~ ram-win~ boat illus~rated is indeed a bo1t which can
10 be operated wi~hout ~equi~i~ any sp~cial ce~i~lcation requjrements.
~ree-flight is avoided owin~ to the reduced propulsion limited Ito the take-
off and t~e confi~uration which simp1y prevellts the cIaft j~from being
vperated as an aircr~t and everl in a lifted pha~e remains a b lat ow~n~ to
the interAction betwee;tl the various parts and t~e water whjch remains
15 throu~houtthe fli~ht phases.
The in~ention is ~ot li~ited to the embodimen~s described
above but all changes a~d modific~ion6 thereof, not corlsti~tin~ dep~tures
fx~m the s~?irit and scope o~ the invention~ ~re intended to be in~luded.
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