Note: Descriptions are shown in the official language in which they were submitted.
A HELICOPTER WEIGHT AND TORQUE ADVISORY SYSTEM
BACKGRO ND OF THE INVENTION
This invention relates to a helicopter advisory system and
more particularly, but not by way of limitation, to a system for
5 providing real time engine torque margin (the difference between
available torque and required torque), gross weight, gross weight
center of gravity and weight supported by the helicopter's cargo
hooks to helicopter personnel for external load carriage missions.
Heretofore, helicopter pilots did not have modern auto-
10 mated means of knowing required engine torque relative to availabletorque as a function of actual external cargo load. The present
process is to manually refer to performance look-up tables and
charts to determine torque margin for an actual external load which
is time consuming, cumberso~le and always subject to error. This
15 manual system may cause helicopter structural damage, inability to
complete missions and unfortunate accidents.
Prior attempts to determine the helicopters conditlon after
lifting external cargo'did not incorporate the real time input of al-
titude, temperature and fuel weight data necessary to determine
20 engine torque margins.
The subject helicopter weight and torque advisory system
ellminates the above mentioned problems and provides unique features
and advantages heretofore not available during helicopter flight.
SUMMARY OF THE INVENTION
According to one aspect of the invention there is provided
a helicopter wei0ht and torque advisory system connected to a
helicopter's i'uel gauge, outside air temperature and altitude indi-
cating system and hook load sensor and operated by one of the heli-
\~
copter's personnel, the system comprising: a control panel and
processor unit connected to the aircraft's power source, hook load
sensor, fuel gauges, outside air temperature and altitude system,
the control panel processor unit including a compu-ter and necessary
5 memory for storing and calculating the helicopter's engine torque
margin, gross weight, gross weight center of gravity and indivi-
dual weight suppcrted by a cargo hook as an external load is raised
by the helicopter; and a remote display unit connected to the pro
cessor unit, the display unit displaying the helicopter's fuel weight,
10 outside air temperature and altitude.
~ ccording to another aspect of the invention there is pro-
vided a helicopter weight and torque advisory system connected to a
helicopter's fuel gauge, outside air temperature and altitude indi-
cating system and hook load sensors and operated by one oE the
15 helicopter's personnel, the system comprising: a control panel and
processor unit connected to the aircraft's power source, hook load
sensor, fuel flow indicating system, outside air temperature gauge,
pressure altitude gauge and anti-ice system, the control panel and
processor unit including a computer and necessary memory for storing
20 and calculating the helicopter's engine torque margin, gross weight,
gross weight center of gravity and individual weight supported by
each of the helicopter's cargo hooks as an external load is raised
by each of the hooks of the helicopter; and a remote display unit
connected to the processor unit, the display unit displaying ~he
25 helicopter's fuel weight, outside air temperature and altitude.
The subject helicopter weight and torque advisory system
displays in real time the helicopter's engine torqua margin, gross
weight, gross weight center of gravity and wei5h-t supported by
each cargo hook as an external load is raised and carried by the
30 helicop ter .
~,.
The system display also alerts the flight crew when re-
quired torque approaches available torque. Also, it displays the
helicopter gross weiyht and gross weight center of gravity (CG)
which flash when a (CG) limit is exceeded. Also, it displays the
5 weight lifted by a cargo hook and flashes when the hook weigh t load
limit is reached.
The system may also be used to compute engine torque
margins at a destination location based on actual external load and
processor unit. The display unll and control panel may be mounted
10 in the cockpit of the helicopter and may be read in direct sunlight
and with or without nlght vision goggles. The control panel por-
tion of the control panel and processor unit consists of an ON/OFF
switch, three mode switches, i . e ., internal cargo load switch
INTERNAL LOAD, sling load switch SLING LOAD and engine torque
15 margin at destination switch DEST. ~lso, it contains a recall key
RCL, a test key TEST and a calibration key CALB. Further, it
includes three data keys, CHANGE, SGROLL and ENTER~ and a
display brightness control knob. The remote display unit consists
of three lines with each line capable of displaying four alpha-numeric
20 characters.
The remote display untt and control panel and processor
unlt are small Eor potential installation ln existing space without dis-
turbing existing equiprnent in the helicopter's cocl~pit.
BRIEF DESCRIPTION OF THE DRAWINGS
-
Fig. 1 illustrates the rernote display unit.
Fig. 2 illustrate.s the control panel of the control panel and
processor unit .
Fig. 3 illustrates a cockpit of a heltcopter for receiving
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the remote display unit and control panel and processor unit.
Figs. 4A and 4B illustrate a system diagram of the advisory
system and processor unit components.
Figs. 5A, 5B, 5C and 5D illustrate the display formats when
5 the on/off switch is engaged.
Figs. 6A, 6B, 6C and 6D illustrate example displays when
the on/off switch is engaged~
Figs. 7A and 7B illustrate the display formats when the
internal load switch is engaged.
Figs. 8A, 8B and 8C illustrate example displays when the
internal load switch is engaged.
Figs. 9A and 9B illustrate the display formats when the
sling load switch is engaged.
Figs. lOA, lOB and lOC illustrate example displays when the
1~ sling load s~itch is engaged.
Flgs. llA and llB illustrate display formats when the
Destlnation (DEST ) switch is engaged .
Figs. 12A and 12B illustrate example displays w~len the
Destination (DEST) switch is engaged.
Fig. 13 illustrates the location of the cargo compartments
in an example CH-~7D helicopter.
Fig. 14 illustrates the location of the external cargo hooks
on the example CH-47D helicopter.
DETAILED DESCRIPTION OF THE DRAWINGS
In Fig. 1 the remote display unit is designated by general
reference numeral 10. The unit 10 includes three lines 12, 14 and 16
each capable of displaying four alpha-numeric characters.
In Fig. 2, the control panel and proce~sor unit is shown
and designated by general reference 18. The unit 18 includes an
on/off switch 20 and three display mode keys, internal load 22, sling
load 24 and destination (DEST) 26.
A second line includes a recall (RCL) key 28, test key 30
and calibration (CALB) key 32. Further a -third line includes three
àata entry keys, change 34, scroll 36 and enter 38. On the unit 18
a display brightness control knob 40 is included for regulating the
brightness of the light to the remote display unit 10.
Shown in Fig. 3 is a cockpit for a CH-47D helicopter showlng
15 where typically, the remote display unit 10 and control panel and
processor unit 18 can be mounted~ The remote display unit 10 and
control panel processor unit 1~ are small enough for potential instal-
lation in e~cisting space without disturbing the equip~nent used with:
various types of helicopters.
In Fig. 4A a system diagram is shown whlch illustrates the
interface between the helicopter weight and torque advisory system
designated by general reference numeral 42 and other helicopter sys-
tems. In this diagram, the remote display unit 10: shown is connected
to the control panel and processor unit 18 via lead 43. The unit l8
25 iS connected via lead 44 to lead 45 which is connected to the fuel
gauging system oi the helicopter. Lead 44 is also connected to lead
46 cbnnected to the outside air temperature sensor system of the heli-
copter and to lead 48 connected to the altitude indicating system of
the helicopter.
In Fig. 4B the computer and necessary memory of the pro-
cessor unit 18 is shown for storing and calculating the helicopter
engine torque margin, gross weight, gross weight center of gravity
and individual weight supported by each individual external cargo
5 hook. The load sensors, fuel gauge and outside air temperature
system are connected to analog to digital converter with multiplexer
56 via leads 45, 46 and 50. The converter 56 is connected to a
single chip processor 58 which in turn is connected to drivers 60.
A keyboard 62 of the unit 18 is connected to an encoder 64 which
10 in turn is connected to the processor 58. The drivers 60 interface
with receivers 66 which are connected to a digit multiplexing control
68 and serial parallel connector 70. The control 68 is connected to
digit drivers 72 and the connector 70 is connected to segment drivers
74. The drivers 72 and 74 are connected to the remote display unit
15 10.
Referring now to Fig. 5A and prior to the start of a mis-
sion, the operator turns the system on using the onloff switch 20.
The display 10 will indicate the total fuel weight on the first line 12,
pressure altitude on the second line 14, and outside air temperature
20 on the third line 16. The values should be the same as those shown
on the helicopters total fuel gauge and the altitude and outside air
temperature indicators. The operator ~ould press the SCROLL key
36 on the control panel 18 to view the helicopters operating weight,
Fig. 5B, operating weight CG, Fig. 5C, and type of engines, Fig. 5D,
25 which are stored in the processor memory. The data entry keys on
the control panel 18, i.e., CHANGE 34, SCROLL 36, and ENTER 38
are used to change the displayed data. The process for entering
or updating data consists of pressing the change key 34 which starts -
the cursor of the display unit 10 blinking at the first data character
30 position. If no change is required at this position, the operator then
presses the enter key 38 and the cursor will shift to the next charac-
ter position. If a character is to be entered or updated, the opera-
tor then presses the SCROLL key 36 to bring up the desired
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character and then the ENTER key 3~ is pressed. The cursor will
then automatically shift to the next character and at the end of the
line, skip to the first data character on the next line. Figs. 6A, 6B,
6C and 6D are examples of the display formats that would appear
5 when the system is turned on and the SCROLL key is used to bring
up displays. The original display format 5A will appear after the
SGROLL key is used when Fi0ure 5D is displayed.
The operator must manually enter the internal cargo load
weight into the system processor prior to the lifting of the external
10 sling load, Thls is accomplished by first engaging the INTERNAL LOAD
switch 22 on the control panel 18 which brings up format Fig. 7P, and
then using the data entry keys CHG 34, SCROLL 36 and ENTER 38.
The system automatically distributes the displayed internal cargo
load weight evenly over the internal cargo compartments C, D and E
15 which are shown in Fig. 13. This weight distribution may be viewed
by pressing the SCROLL key and the display format would be as
shown in 7B. If the internal cargo load weight is not distributed
evenly, the operator would enter the unevenly distributed load into
the processor using the Fig. 7B format and the data entry keys CHG
20 34, SCROLL 36 and ENTER 38. Figs. 8A and 8B illustrate an exam-
ple of a 16,000 pound internal payload evenly distributed and non-
evenly distributed in Fig. 8C.
Prior to lifting an external load, the operator would engage
the SLI~lG LOAD switch 24. The display format that will appear is
25 shown in Fig. 9A. As the external sling load is raised, the helicopter
gross weight shown in the first line 12 of the display 10 would in-
crease, as well as the total sling load weight shown in the second
line 14 of the display 10. Also, as the external sling load is raised,
the torque margin for two engines and single engine operation would
30 decrease and would be displayed in the third line 16 of the display
10. An example of an actual display is shown in Fig. 10A.
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If the helicopter gross weight limit is exceeded as a result
of an adverse balance (center of gravity) condition, a "F" for
forward CG limit condition or an "A" for aft CG limit condition would
appear in the first position of line 12 oi the display 10 and the entire
5 line would start i~ashing. If the weight limit of external cargo hooks,
76, 78 or 80 shown in Fig. 14 is exceeded, the hook that is over-
loaded will appear in the first position of line 14 of the display 10 and
the entire line 14 of the display 10 will i~ash. An "A" in the first
position would indicate forward hook 76, "C" the center hook 78 and
10 "D" the aft hook 80. If a torque margin (available torque minus
required torque) for either a two engine or single engine operation
is exceeded, the torque margin displayed which was exceeded in
line 16 of display 10 would start flashing. This is shown in Fig. 10B~
If the operator wants to view the individual sling load
15 weights, he would press the scroll key 36 and the display format
9B displaying the individual sling loads supported by rack hook would
be displayed. The hook position and the sling weight it is supporting
are displayed and ii any of the hook load limit weights exceeded their
load limit, its weight value and hook identification symbol (F, C, A)
20 would flash. An example is shown in Fig. 10C. The operator
would press either SCROLL 36 or SLING LOAD 2~ to return to the
original sling load format display 9A.
The desitnation (DEST) switch 26 is used to determine the
engine torque margins at the mission destination point based on
25 actual sling load and the internal load and anticipated remaining fuel
weight, altitude and temperature at the mission destination point~
When the destination switch 26 is engaged, the anticipated destination,
altitude and air temperature would be displayed as shown in Fig. llA
and an example in Fig. 12A. These values may be updated by the
30 operator using the data entry keys. Next, the operator would press
the scroll key 36 to display and update the anticipated remaining
~l2~
g
fuel at destination. The destination remaining fuel value is shown
on the second line of Fig. llB and an example in Fig. 12B. The
resulting torqu~ margins at destination are displayed on the third
line of Fig. llB and will flash if they are exceeded.
The recall key RCL 28, on the control panel 18 is used to
display the same data that appears when the system is turned on
(Fig. 5). The test key TEST, 30, is used for built-in-test pur-
poses. The calibration key CALB 32, is used to calibrate the system
processor with the discretes from the external cargo hooks, fuel
10 gauge and altitude and air temperature indicators.
Changes may be made in the construction and arrangement
of the parts or elements of the embodiments as described herein
without departing from the spirit or scope of the invention defined
in the following claims.
