U.S. patent application number 15/205162 was filed with the patent office on 2017-04-06 for modular and morphable air vehicle.
This patent application is currently assigned to Piasecki Aircraft Corporation. The applicant listed for this patent is Piasecki Aircraft Corporation. Invention is credited to Brian Geiger, Douglas Johnson, Frederick W. Piasecki, John W. Piasecki, David Pitcairn.
Application Number | 20170096221 15/205162 |
Document ID | / |
Family ID | 50425309 |
Filed Date | 2017-04-06 |
United States Patent
Application |
20170096221 |
Kind Code |
A1 |
Piasecki; John W. ; et
al. |
April 6, 2017 |
Modular and Morphable Air Vehicle
Abstract
An unmanned air module includes one or more rotors, engines, a
transmission and avionics. Any of several different ground modules
may be attached to the air module. The air module may fly with and
without the ground module attached. The ground module may be
manned. The air module may have two rotors, which may be ducted
fans. The air module may include a parachute, an airbag and landing
gear.
Inventors: |
Piasecki; John W.; (Bryn
Mawr, PA) ; Piasecki; Frederick W.; (Haverford,
PA) ; Geiger; Brian; (Glen Mills, PA) ;
Johnson; Douglas; (Prospect Park, US) ; Pitcairn;
David; (Essington, PA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Piasecki Aircraft Corporation |
Essington |
PA |
US |
|
|
Assignee: |
Piasecki Aircraft
Corporation
Essington
PA
|
Family ID: |
50425309 |
Appl. No.: |
15/205162 |
Filed: |
July 8, 2016 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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14684995 |
Apr 13, 2015 |
9393847 |
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15205162 |
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13068601 |
May 16, 2011 |
9045226 |
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14684995 |
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61416965 |
Nov 24, 2010 |
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61345535 |
May 17, 2010 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B64C 27/20 20130101;
B64C 3/56 20130101; B64C 27/22 20130101; B64C 29/0033 20130101;
B64C 39/00 20130101; B64D 25/00 20130101; B64C 27/08 20130101; B64D
2201/00 20130101; B64C 27/52 20130101; B64C 25/58 20130101; B64C
3/385 20130101; B64C 11/001 20130101; B64C 27/57 20130101; B64C
27/32 20130101; B64C 37/00 20130101; B64C 39/02 20130101; B60F 5/02
20130101; B64D 17/80 20130101; B64C 29/00 20130101; G05D 1/102
20130101 |
International
Class: |
B64C 37/00 20060101
B64C037/00; B64D 17/80 20060101 B64D017/80; B64C 29/00 20060101
B64C029/00; B64C 25/58 20060101 B64C025/58; B64C 3/56 20060101
B64C003/56; B64C 27/22 20060101 B64C027/22; B60F 5/02 20060101
B60F005/02; B64D 25/00 20060101 B64D025/00 |
Claims
1. A personal air vehicle apparatus, the apparatus comprising: a.
an air module, said air module being unmanned; b. a first rotor and
a second rotor operably attached to said air module, said first
rotor having a first rotor axis of rotation, said second rotor
having a second rotor axis of rotation, said first and second rotor
axes of rotation being selectably tiltable about an axis of rotor
tilt between a horizontal position and a vertical position; c. a
ground module, said ground module and said air module being
configured to be selectably attached one to the other, said first
and second rotors in combination being configured to support said
ground module and said air module in a flight when said ground
module and said air module are attached, said first and second
rotors in combination being configured to support said air module
in said flight when said ground module and said air module are not
attached; d. a first circular duct surrounding a periphery of said
first rotor; e. a second circular duct surrounding said periphery
of said second rotor, said first rotor in combination with said
first circular duct defining a first ducted fan, said second rotor
in combination with said second circular duct defining a second
ducted fan, said first circular duct and said second circular duct
defining a first and a second circular wing, said first and said
second circular wings providing a lift to said air module when said
air module is flying and said first and second rotor axes of
rotation are in said horizontal position; f. a control system, said
control system being configured to detect an aircraft condition of
said air module during flight; g. a ballistic parachute configured
to lower said air module or said ground module to a ground, said
control system being configured to trigger said ballistic parachute
if said control system detects said aircraft condition.
2. The personal air vehicle of claim 1, said ballistic parachute
comprising: a parachute mortar attached to said air module or said
ground module and configured to launch said ballistic parachute
upon command by said control system, said parachute mortar being
capable of pointing said ballistic parachute in a direction
selected by said control system.
3. The personal air vehicle of claim 2 wherein said control system
selects said direction for projection of said ballistic parachute
to accommodate a motion of said air module or said ground
module.
4. The personal air vehicle of claim 3 wherein said control system
selects said direction to accommodate an attitude of said air
module or said ground module.
5. The personal air vehicle of claim 3 wherein said control system
is configured to continuously monitor said motion and said attitude
and to continuously select said direction and to point said
parachute mortar based on said motion and said attitude.
6. The personal air vehicle of claim 1, said ballistic parachute
comprising: a steerable rocket attached to said air module or said
ground module and configured to launch said ballistic parachute
upon command by said control system.
7. The personal air vehicle of claim 6 wherein said control system
is configured to select a direction for launch of said ballistic
parachute to accommodate a motion and an attitude of said air
module or said ground module.
8. The personal air vehicle of claim 7 wherein said control system
is configured to steer said rocket in said selected direction.
9. The personal air vehicle of claim 1, the personal air vehicle
further comprising: an air bag, said air bag being attached to a
bottom side of said ground module, said air bag being configured to
inflate and to slow an impact between said ground module and a
ground.
10. The personal air vehicle of claim 9, further comprising: a
landing gear, said landing gear being attached to said ground
module, said landing gear being configured to absorb said impact
remaining after inflation of said air bag to protect an occupant of
said ground module.
11. A personal air vehicle apparatus, the apparatus comprising: a.
an air module; b. at least one rotary wing operably attached to
said air module, said at least one rotary wing comprises a first
rotor and a second rotor, said first rotor having a first rotor
axis of rotation, said second rotor having a second rotor axis of
rotation, said first and second rotor axes of rotation being
selectably tiltable about an axis of rotor tilt between a
horizontal position and a vertical position; c. a ground module,
said ground module and said air module being configured to be
selectably attached one to the other, said at least one rotary wing
being configured to support said ground module and said air module
in a flight when said ground module and said air module are
attached, said rotary wing being configured to support said air
module in said flight when said ground module and said air module
are not attached; d. a first circular duct surrounding a periphery
of said first rotor; e. a second circular duct surrounding said
periphery of said second rotor, said first rotor in combination
with said first circular duct defining a first ducted fan, said
second rotor in combination with said second circular duct defining
a second ducted fan, said first circular duct and said second
circular duct defining a first and a second circular wing, said
first and said second circular wings providing a lift to said air
module when said air module is flying and said first and second
rotor axes of rotation are in said horizontal position; f. a first
wing extension and a second wing extension, said first wing
extension being attached to said first circular duct, said second
wing extension being attached to said second circular duct, said
first and second wing extensions providing said lift to said air
module when said air module is flying with said first and second
rotor axes of rotation are in said horizontal position; g. a
control system, said control system being configured to detect an
aircraft condition of said air module during flight; h. a ballistic
parachute configured to lower said air module or said ground module
to a ground, said control system being configured to trigger said
ballistic parachute if said control system detects said aircraft
condition.
12. The personal air vehicle of claim 11, said ballistic parachute
comprising: a parachute mortar attached to said air module or said
ground module and configured to launch said ballistic parachute
upon command by said control system, said parachute mortar being
capable of pointing said ballistic parachute in a direction
selected by said control system.
13. The personal air vehicle of claim 12 wherein said control
system selects a direction for projection of said ballistic
parachute to accommodate a motion of said air module or said ground
module.
14. The personal air vehicle of claim 13 wherein said control
selects said direction based on an attitude of said air module or
said ground module.
15. The personal air vehicle of claim 14 wherein said control
system is configured to continuously monitor said motion and said
attitude of said air module and to point said parachute mortar
based on said motion and said attitude.
16. The personal air vehicle of claim 11, said ballistic parachute
comprising: a steerable rocket attached to said air module or said
ground module and configured to launch said ballistic parachute
upon command by said control system.
17. The personal air vehicle of claim 16 wherein said control
system is configured to steer said steerable rocket to accommodate
a motion and an attitude of said air module or said ground
module.
18. The personal air vehicle of claim 11, the personal air vehicle
further comprising: an air bag, said air bag being attached to a
bottom side of said ground module, said air bag being configured to
inflate and to slow an impact between said ground module and a
ground.
19. The personal air vehicle of claim 18, further comprising: a
landing gear, said landing gear being attached to said ground
module, said landing gear being configured to absorb said impact
remaining after inflation of said air bag to protect an occupant of
said ground module.
Description
RELATED APPLICATIONS
[0001] This continuation patent application is entitled to priority
from U.S. Provisional Patent Application 61/345,535, filed May 17,
2010 by John W. Piasecki and others and from U.S. Provisional
Patent Application No. 61/416,965 filed Nov. 24, 2010 by John W.
Piasecki and others, which applications are incorporated by
reference in this document as if set forth in full herein. This
application claims priority from U.S. utility patent application
Ser. No. 13/068,601 filed May 16, 2011 by John W. Piasecki and
others and issued as U.S. Pat. No. 9,045,226 on Jun. 2, 2015, which
application and patent are incorporated by reference in this
document as if set forth in full herein. This application claims
priority from U.S. utility application Ser. No. 14/684,995 filed
Apr. 13, 2015 by John W. Piasecki and others, which will issue as
U.S. Pat. No. 9,393,847 on Jul. 19, 2016. All of the above
applications and patents are entitled "Modular and Morphable Air
Vehicle." The following documents attached to and incorporated by
reference into provisional application 61/345,535 are hereby
incorporated by reference as if set forth in full herein: [0002] A.
PiAC Proposal No. 459-X-1, pages 3 through 26 [0003] B. PiAC Report
No. 459-X-2, pages 1 through 35 [0004] C. PiAC Proposal No.
159-X-50, pages 3 through 47.
BACKGROUND OF THE INVENTION
[0005] A. Field of the Invention
[0006] The Invention is a personal air vehicle (`PAV`) that is
modular. The PAV includes an unmanned air module and a ground
module that may be releasably attached to the air module. The
ground module may be a wheeled passenger vehicle and may be driven
on the ground under its own power either with or without the air
module attached. Alternatively, the ground module may be a medical
module, a cargo module, a weapons module, a passenger module or a
communications module. The air module can fly either with or
without the ground module engaged and can support the ground module
in flight in any of three different configurations. The air module
and ground module combination may fly as a rotary wing aircraft and
also may fly as a tilted-rotor, fixed wing aircraft. Alternatively,
the air module may fly as an open rotor rotary wing aircraft with
or without tilted-rotor capability or may fly as an autogyro with
or without jump capability.
[0007] B. Description of the Related Art
[0008] The prior art does not teach the modular, optionally manned,
morphing, autonomous PAV of the invention.
BRIEF DESCRIPTION OF THE INVENTION
[0009] The invention is a personal air vehicle. The personal air
vehicle includes an unmanned air module and any of several
different ground modules, which may be manned or unmanned. The air
module may fly independently of the ground module. The air module
and ground module may be selectably engaged to morph the air module
into an air and ground module combination. The air module may
support the ground module in flight. The ground module may support
the air module when the air module and attached ground module are
on the ground. The ground module may be a vehicle ground module and
may support the attached air module on the ground, both when the
vehicle ground module is stationary and when the vehicle ground
module is moving on the surface of the ground.
[0010] A. Ground Module
[0011] The ground module may be a vehicle ground module that is
capable of transporting adult human beings over the ground under
its own power, either with or without the air module attached.
Alternatively, the ground module may be a cargo/payload module, a
medical transport module, a weapons system platform, a passenger
module, a communications module or may be configured to contain any
other load that a user may wish to transport through the air.
[0012] The ground module and air module combination may be
configured to accommodate human beings and to transport those human
beings through the air. For example, the medical module is
configured to accommodate human patients and a human attendant. The
ground vehicle module is configured to accommodate one or more
soldiers and their equipment.
[0013] B. Air Module
[0014] The air module includes at least one rotary wing. The, at
least one rotary wing is configured to support the air module in
flight. The at least one rotary wing also is configured to support
the ground module and any cargo and human passengers that are
inside the ground module in flight when the ground module is
attached to the air module. The air module includes the engine(s),
rotors, drive system, avionics, sensors, communications relays and
autopilot control system to allow the air module to fly.
[0015] The air module is autonomous and unmanned. As used in this
document, the term "autonomous" means that the air module may
take-off, fly and land under the control of an autopilot control
system. As used in this document, the term "unmanned" means that
the air module does not accommodate a human pilot on board the air
module, although a human operator may program the autopilot control
system prior to flight, including selection of a mission plans,
waypoints and a landing zone. During flight, a human operator also
may select or change the mission plan, waypoints and landing point
from a remote station or from a ground module or may control the
air module remotely.
[0016] 1. Twin Ducted-Fan Air Module
[0017] The air module may use any configuration of rotary wings
known in the aircraft art to support an aircraft in flight. In one
embodiment, the air module features two ducted fans joined by a
central unit. Each ducted fan comprises a circular duct surrounding
a rotor. The central unit houses the engine(s), drive system for
the two ducted fans, starter batteries, flight avionics, optional
sensors, communications relays and autopilot control system. The
air module landing gear can double as a load-carrying structure for
attachment to the ground module. The two rotors in the two ducted
fans are rigid in that flapping or lead and lag hinges are not
provided. The use of rigid rotors provides flexibility in
accommodating changes to the center of gravity of the aircraft. The
air module featuring ducted fans is referred to herein as the
"ducted fan air module."
[0018] The twin ducted fan air module can transition among three
different configurations in flight (that is, `in stride`) while
supporting the ground module. In the first, or tandem rotor
configuration, the two ducted fans are oriented fore-and-aft along
the longitudinal axis of the ground module with the axes of
rotation of the two rotors in a generally vertical direction. In
the second, or side-by-side rotor configuration, the two ducted
fans are located on either side of the longitudinal axis of the
ground module with the axes of rotation of the two rotors generally
in a vertical direction. In both the tandem and side-by-side rotor
configurations the air module flies as a rotary wing aircraft.
[0019] In the third, or tilted-rotor configuration, the ducted fans
are located on either side of the ground module, as in the
side-by-side rotor configuration, but with the axes of rotation of
the two rotors oriented generally parallel to the longitudinal axis
of the ground module. In the tilted-rotor configuration, the air
module flies as a tilted-rotor, fixed-wing aircraft with the rotors
serving as propellers urging the aircraft forward.
[0020] When in the tilted-rotor configuration, the two ducts for
the ducted fans serve as circular wings. The forward movement of
the air module moves air over the circular wings, providing lift to
the air module. A wing extension may be attached to the outboard
end of each of the ducts for the two ducted fans. The wing
extensions may be hinged to reduce the size of the air module when
the wing extensions are not providing lift. The two wing extensions
provide additional wingspan and wing area and hence provide
additional lift to the air module in the tilted-rotor
configuration. The two wing extensions may be arcuate in shape and
may conform to the shape of the circular ducts for compact storage.
The central unit also may be of an airfoil shape. The circular
wings, the wing extensions and the central unit provide lift to
support the weight of the air module and the ground module in
flight when the air module is in the tilted-rotor configuration and
moving forward through the air.
[0021] Operation in the tandem rotor configuration provides the air
module with a narrow profile and allows the aircraft to operate in
confined urban settings and even allows cargo or passengers to be
loaded or unloaded to and from upper stories of buildings. The
tandem rotor configuration involves penalties in hover performance
because the downwash of the ducted fans is partially obstructed by
the fore and aft portions of the ground module. The side-by-side
rotor configuration avoids the downwash penalty, but the larger
profile presented by the vehicle restricts operation in confined
areas. The tilted-rotor configuration provides for a higher air
speed and longer range of flight than is possible in either the
tandem or side-by-side rotor configurations.
[0022] Each of the rotors is connected to the central unit using a
torsion beam that is flexible in torsion, which allows the rotors
and ducts to tilt with respect to each other when twisting moments
are applied to the torsion beams. The torsion beams supports the
ground module when the PAV is in flight. The torsion beams also
support the rotors on the ground module when the PAV is on the
ground. The rotors have differential and non-differential
monocyclic pitch control in the direction normal to the axis of
rotor tilt of the two rotors. The rotors also have differential and
non-differential collective pitch control. The combination of the
torsion beam and monocyclic pitch control, along with collective
pitch control, allows control of the PAV in all axes in all three
configurations. The ducted fans may be equipped with exit vanes
that swivel about a vane axis parallel to the axis of rotor tilt.
The vanes provide redundant control to the monocyclic pitch control
and may provide additional wing area and hence additional lift when
the air module is in the tilted-rotor configuration.
[0023] Yaw control: When the air module is in the first (tandem) or
second (side-by-side) rotor configuration, applying differential
monocyclic pitch applies a twisting moment to the flexible torsion
beam, tilting the rotors differentially and allowing the rotors to
apply a yawing moment to the aircraft, hence controlling yaw. In
the tandem and side-by-side rotor configurations, differential vane
angle control also controls yaw. When the aircraft is in the third
(tilted-rotor) configuration, applying differential collective
pitch to the two rotors controls yaw.
[0024] Pitch control: When the aircraft is in the first (tandem)
rotor configuration, applying differential collective pitch to the
rotors controls aircraft pitch. When in the side-by-side rotor
configuration or the tilted-rotor configuration, applying
non-differential monocyclic pitch to the rotors applies a pitching
moment to the aircraft, controlling aircraft pitch. In the
tilted-rotor configuration, vane angle control also controls
aircraft pitch. Exhaust gas from the engine(s) may be vectored to
provide additional pitching moments in the tilted-rotor or tilt
duct configuration.
[0025] Roll control: When the aircraft is in the first (tandem)
rotor configuration, applying non-differential monocyclic pitch to
the rotors applies a rolling moment to the aircraft, controlling
roll. When the aircraft is in the second (side-by-side) rotor
configuration, applying differential collective pitch to the rotors
controls roll. When the aircraft is in the third (tilted-rotor)
configuration, applying differential monocyclic pitch to the rotors
applies a rolling moment to the aircraft, controlling roll.
Differential vane control also will control roll in the
tilted-rotor configuration.
[0026] During transition from the side-by-side rotor configuration
to tilted-rotor configuration, non-differential monocyclic pitch
assists the rotors in tilting to the tilted-rotor configuration,
allowing use of smaller and lighter effectors to accomplish the
transition.
[0027] 2. Open Rotor Air Module
[0028] The air module may dispense with circular ducts surrounding
the one or more rotors. Such an air module is hereinafter referred
to as an "open rotor air module." The open rotor air module also
features a central unit that houses the engine(s), drive system,
starter batteries, flight avionics, optional sensors,
communications relays and autopilot control system. The central
unit also can provide landing gear to support the open rotor air
module when the open rotor air module is not flying and is not in
engagement with the ground module. The central unit provides an
attachment location between the open rotor air module and ground
module, allowing the air module to morph to a combination of an air
module and a ground module. If the air module utilizes a single
rotor, either an open rotor or a ducted fan, a reaction thruster is
provided to counteract the moment of the turning rotor, as in a
conventional single rotor helicopter. The reaction thruster can be
a propeller, ducted fan, turbojet or any of the reaction thrusters
known in the rotary wing aircraft art. If two rotors are utilized,
either ducted fans or open rotors, the rotors will be
counter-rotating, avoiding the need for the reaction thruster. The
two counter-rotating open rotors may be coaxial, may be
intermeshing, may be located in tandem and may be located
side-by-side.
[0029] The open rotor air module may feature two open rotors
connected to and powered by the central unit. The twin open rotor
air module may be capable of transitioning among the tandem rotor
configuration, the side-by-side rotor configuration and the
tilted-rotor configuration, as described above for the twin
ducted-fan air module. The twin open rotor air module does not
feature ducts and hence does not feature circular wings; however,
the open rotor air module may feature a tilt wing and may feature
deployable wing extensions. In all other respects, the descriptions
and figures of this application applicable to the twin ducted fan
air module apply equally to a twin open rotor air module.
[0030] The air module also may be configured with three or more
rotors all connected to and powered by the central unit. The three
or more rotors may be open rotors or ducted fans.
[0031] Unless the context otherwise requires, as used in this
application the term "air module" refers to both a ducted fan fair
module and an open rotor air module.
[0032] 3. Autogyro Air Module
[0033] The air module may be an autogyro, which may be a `jump`
autogyro. In the jump autogyro air module, an open rotor is
connected to an engine located in the central unit. The engine will
turn the rotor to prepare the air module for takeoff. Turning the
rotor temporarily stores kinetic energy in the rotor. To take off,
the spinning rotor is disengaged from the engine and the collective
pitch of the autogyro rotor blades is increased. The kinetic energy
of the spinning rotor blades is converted to lift and the jump
autogyro air module rises vertically from the ground.
[0034] Either before takeoff or during the ascent, the engine is
connected to a propeller or other vectored thruster that urges the
jump autogyro air module forward. As the airborne jump autogyro air
module accelerates forward, air passes through the rotor disc from
the lower side of the disc to the upper side. Once the jump
autogyro air module reaches an adequate forward speed, the air
moving through the rotor disc due to the forward motion of the air
module maintains the rotational speed of the rotor and the air
module remains airborne. The jump autogyro therefore may take off
vertically and continue to fly after takeoff. The jump autogyro air
module has a single configuration in flight.
[0035] The autogyro air module is modular and may support a ground
module in flight, just as a ducted fan air module or an open rotor
air module may support a ground module. The control and other
systems of the jump autogyro air module operate as do the
equivalent systems of the ducted fan and open rotor air modules.
The autogyro, ducted fan and open rotor air modules may be used
interchangeably with a ground module.
[0036] 4. Multiple Air Modules Carrying a Single Load
[0037] The ability of an air module to support a load in flight is
limited by the capabilities of the air module; however, two or more
air modules may cooperate to transport a single load that is too
large or too heavy to be transported by a single air module. The
number of air modules that may be attached to a load is limited
only by the space physically available on the load for attachment
of the air modules. For large or heavy loads, the air modules may
be attached to a interconnecting structure and the load supported
by the interconnecting structure. The twin ducted fan or twin open
rotor air modules described above may fly in any of the tandem,
side-by-side or tilted-rotor configurations when two or more of
those air modules are cooperating to transporting a large or heavy
load.
[0038] The autopilot control systems of the two or more air modules
cooperate to coordinate control among all of the air modules
supporting the large or heavy load.
[0039] 5. Control System
[0040] The autopilot control system of the air module is housed in
the central unit of the unmanned air module. The autopilot control
system includes a microprocessor, computer memory, data links,
sensors and control effectors. The autopilot control system allows
a mission plan to be pre-programmed into the computer memory,
including waypoints and landing zone location. A human operator at
a remote location or in the ground module may change the mission
plan, waypoints or landing zone location during flight. The
autopilot control system allows the air module to operate
autonomously and independently of a ground module.
[0041] The air module control system allows the air module or the
air module and ground module combination to transition among the
first, second and third configurations `in stride.` As used in this
document, the term `in stride` means that the air module may
transition among the tandem rotor configuration, the side-by-side
rotor configuration and the tilted-rotor configuration starting
during hover or low speed flight or during on-road travel by the
air module and ground module combination. While traveling on the
ground, the air module and ground module combination may transition
to the third (tilted-rotor) configuration, take off, fly and land
as a short takeoff and landing (STOL) aircraft.
[0042] The air module can be configured to fly autonomously,
including flying autonomously to a safe location after disengaging
with the ground module, flying to and re-engaging with the ground
module when needed, autonomously engaging with and transporting
cargo containers, and autonomously engaging and transporting
medical transportation units, such as to evacuate a wounded soldier
from a battlefield. The air module also may operate under manual
human control, in a fly-by-wire configuration or by remote
control.
[0043] 6. Active Center-of-Gravity Control
[0044] The air module or ground module may be equipped with active
center of gravity (CG) control. The CG control detects changes in
the center of gravity of the airborne aircraft, such as by soldiers
and equipment embarking and disembarking from the ground module
while the aircraft is in hover, and adjusts the CG accordingly to
maintain the commanded attitude of the aircraft. Attitude sensors
detect the attitude of the aircraft and supply the attitude
information to the microprocessor. The microprocessor compares the
detected attitude to the commanded attitude of the aircraft. If
there is a discrepancy, the microprocessor activates actuators and
adjusts the relative position of the center of lift and the center
of gravity to restore the commanded attitude.
[0045] Center of gravity adjustment may involve moving the center
of gravity with respect to the center of lift by moving the ground
module with respect to the air module so that the center of gravity
of the aircraft, its load and it occupants is directly below the
center of lift of the rotor(s) and wing when the aircraft is flying
at the commanded attitude.
[0046] Alternatively, active CG control may take the form of moving
the center of lift of the air module with respect to the ground
module. For example, differential collective pitch applied to the
rotors of the two rotor embodiment having three configurations will
adjust the center of lift along the rotor axis of tilt. For the
open rotor air module and gyrocopter air module, active CG control
may involve moving the rotor with respect to the air module, as by
tilting the rotor pylon or traversing the rotor attach point.
Lateral CG errors are as well managed by the use of a mechanical
motion to displace the center of lift to meet the line of action
imparted by the lift system directly thru the center of
gravity.
[0047] Active CG control also can raise or lower the ground module
with respect to the air module, allowing CG control in three
dimensions.
[0048] Active CG control may include both moving the center of
gravity and moving the center of lift.
[0049] 7. Rotor Configuration
[0050] The air module may be equipped to change the configuration
of the rotor, particularly of open rotor or autogyro air modules
for takeoff and landing. The rotor mast of an open rotor or
autogyro air module may be extended to provide additional ground
clearance to avoid injury to persons near the air module and damage
to the rotors during takeoff or landing.
[0051] The rotor blades of the open rotor or autogyro air module
may be telescoping or otherwise extendable to allow changes in
diameter of the rotor disc. The use of extendable rotor blades
allows the air module to be transportable over the road, as when
the air module is supported by the operating ground vehicle module,
with the rotor blades in the contracted or non-extended position.
When the rotor disc is in the contracted or non-extended position,
the rotor presents a smaller cross section and allows the air
module to avoid obstacles on the ground. By extending the blades,
the area of the rotor disc is increased, allowing better vertical
flight performance than could otherwise be achieved with the
smaller radius of the retracted system.
[0052] The rotor blades of the open rotor air module or the
autogyro air module may be foldable, as is known in the art, so
that the air module presents a smaller cross section while
traveling on the ground and to avoid obstacles on the ground.
[0053] In an example application of the invention, a twin ducted
fan air module is attached to vehicle ground module. The air module
is unmanned and is programmed to transports soldiers occupying the
ground vehicle module on a mission. The air module takes off in the
side-by-side configuration and the air module autopilot follows a
pre-determined mission plan to a pre-selected location along
pre-selected way points. For higher speed and longer range, the air
module transitions to the tilted-rotor configuration during flight.
The soldiers alter the mission plan in flight by selecting an
alternative landing point in an urban area. The air module
transitions to the tandem rotor configuration during flight and the
air module and ground module combination lands at the selected
urban landing zone. The air module and ground module disengage and
the air module takes off. The soldiers in the ground module drive
the ground vehicle module over the ground to the objective. The air
module may fly overhead and communicate with the soldiers in the
ground vehicle module to provide surveillance or airborne weapons
support or may fly to a predetermined safe landing zone and await
instructions. Upon command, the air module flies to the location of
the ground module, reattaches to the ground module and transports
the vehicle ground module and the soldiers back to base.
BRIEF DESCRIPTION OF THE DRAWINGS
[0054] FIG. 1 is a perspective schematic drawing of the twin rotor,
three configuration embodiment in the tandem rotor
configuration.
[0055] FIG. 2 is a perspective schematic drawing of the twin rotor,
three configuration embodiment in the side-by-side rotor
configuration.
[0056] FIG. 3 is a perspective schematic drawing of the twin rotor,
three configuration embodiment in the tilted-rotor
configuration.
[0057] FIG. 4 is a perspective view of the twin rotor ducted air
module in rotary wing flight without a ground module attached.
[0058] FIG. 5 is a perspective view of the twin rotor ducted fan
air module in the tilted-rotor configuration.
[0059] FIG. 6 is a perspective view of the twin rotor, three
configuration air module in the tilted-rotor configuration with a
vehicle ground module attached.
[0060] FIG. 7 is a front view of the twin rotor, three
configuration air module with a vehicle ground module attached and
on the ground.
[0061] FIG. 8 is a perspective view of the twin rotor, three
configuration air module in the tilted-rotor configuration with a
different ground module attached.
[0062] FIG. 9 is a perspective view of the open rotor twin rotor
air module in the tandem rotor configuration with a vehicle ground
module attached.
[0063] FIG. 10 is a perspective view of the open rotor twin rotor
air module in the side-by-side rotor configuration with the vehicle
ground module attached.
[0064] FIG. 11 is a perspective view of the open rotor twin rotor
air module in the tilted-rotor configuration with the vehicle
ground module attached.
[0065] FIG. 12 is a detail cross section view of a ducted fan.
[0066] FIG. 13 is a perspective schematic view of the twin rotor
air module and ground module combination having a torsion beam and
monocyclic pitch in the side-by-side rotor configuration.
[0067] FIG. 14 is a perspective schematic view of the twin rotor
air module and ground module combination having a torsion beam and
monocyclic pitch in the tilted-rotor configuration.
[0068] FIG. 15 is a plan view of a two air module embodiment in the
side-by-side rotor configuration.
[0069] FIG. 16 is a side view of a two air module embodiment in the
tandem rotor configuration.
[0070] FIG. 17 is a plan view of the two air module embodiment in
the tandem rotor configuration.
[0071] FIG. 18 is a perspective view of the two air module
embodiment and ground module combination in the tilted-rotor
configuration.
[0072] FIG. 19 is a perspective view of the two air module
embodiment and scaffold combination in the tilted-rotor
configuration.
[0073] FIG. 20 is a schematic diagram of active CG control.
[0074] FIG. 21 is a detail view of a passive center of gravity (CG)
control.
[0075] FIG. 22 is a detail view of an active CG control in one
dimension.
[0076] FIG. 23 is a detail view of a combination of active and
passive CG control.
[0077] FIG. 24 is a detail view of active CG control in three
dimensions.
[0078] FIG. 25 is a plan view of the active CG control of FIG.
25.
[0079] FIG. 26 is a detail view of active CG control in three
dimensions.
[0080] FIG. 27 is a perspective view of the aircraft with a
parachute.
[0081] FIG. 28 is a schematic of an inflatable bag.
[0082] FIG. 29 is a schematic diagram of the control system.
[0083] FIG. 30 is a schematic diagram of the control system.
[0084] FIG. 31 is a schematic diagram of the control system.
[0085] FIG. 32 is a perspective view of a single open rotor
embodiment.
[0086] FIG. 33 is a perspective view of a coaxial open rotor
embodiment.
[0087] FIG. 34 is a perspective view of an autogyro air module and
ground module combination.
[0088] FIG. 35 is a partial cutaway view of a tilting, extendable
mast for an autogryo air module.
[0089] FIG. 36 is a detail of a tilting mast for an open rotor air
module.
[0090] FIG. 37 is a detail cross section of an extendable mast for
a open rotor air module, with the mast in the retracted
position.
[0091] FIG. 38 is a detail cross section of an extendable mast for
an open rotor air module with the mast in the extended
position.
[0092] FIG. 39 is a perspective view of an extendable rotor in the
retracted position.
[0093] FIG. 40 is a perspective view of an extendable rotor in the
extended position.
[0094] FIG. 41 is a cutaway view of the extendable rotor in the
retracted position.
[0095] FIG. 42 is a cutaway view of the extendable rotor in the
extended position.
DESCRIPTION OF AN EMBODIMENT
[0096] The invention is an air vehicle having at least one rotary
wing 4. The air vehicle may be modular and may transition between
different configurations while still providing transportation
function.
[0097] A. Two Rotor Embodiment Having Three Configurations
[0098] FIGS. 1, 2 and 3 illustrate the elements for a twin rotor
air vehicle that can transition between three different
configurations. The twin rotor embodiment includes a fuselage 3 and
a first rotor 14 and a second rotor 16. The first rotor 14 and the
second rotor 16 are configured to support the fuselage 3 in flight.
The twin rotor air vehicle may be modular, in which case the first
and second rotors 14, 16 along with the drive and control system
for the rotors 14, 16 define an air module 2 and the fuselage 3
defines a ground module 6, as shown by FIGS. 4 through 8 and
discussed below. The air module 2 and the ground module 6 may be
selectably detached.
[0099] The fuselage 3 defines a longitudinal axis 8 in a fore and
aft direction 10, 12 and generally oriented along a preferred
direction of flight for the fuselage 3.
[0100] The first rotor 14 has a first rotor axis of rotation 24 and
the second rotor 16 has a second rotor axis of rotation 26, about
which the first and second rotors 14, 16 are configured to rotate.
The first and second rotor axes of rotation 24, 26 are in a
spaced-apart relation along an axis of rotor tilt 20. The first and
second rotor axes of rotation 24, 26 generally are parallel and
together generally define a plane.
[0101] The axis of rotor tilt 20 may rotate selectably about a
translation axis 28 between the tandem position 22 shown by FIG. 1,
in which the axis of rotor tilt 20 is parallel to the longitudinal
axis 8, and the side-by-side position 30 shown by FIG. 2 in which
the axis of rotor tilt 20 is generally normal to the longitudinal
axis 8. When the first and second rotor axes of rotation 14, 16 are
in the side-by-side position 30, the plane generally defined by the
first and second rotor axes of rotation 14, 16 is generally normal
to the longitudinal axis 8. The first and second rotor axes of
rotation 14, 16 are configured to move selectably between a
vertical position 34, shown by FIGS. 1 and 2, and a horizontal
position 36, shown by FIG. 3.
[0102] The first and second rotors 14, 16 are configured to move
between three different flight configurations. The first flight
configuration is the tandem rotor configuration 18 shown by
FIG.
[0103] 1. When the axis of rotor tilt 20 is in the tandem position
22 and the rotor axes of rotation are in the vertical position 34,
the first and second rotors 14, 16 are in the tandem rotor
configuration 18. In the tandem rotor configuration 18, the first
and second axes of rotation 24, 26 are generally normal to and
generally intersect the longitudinal axis 8 and the longitudinal
axis 8 generally falls on the plane defined by the first and second
rotor axes of rotation 8. The air vehicle can fly in the tandem
rotor configuration 18 as a rotary wing aircraft.
[0104] The second flight configuration is the side-by-side rotor
configuration 32 shown by FIG. 2. From FIG. 2, the air module 2 is
in a side-by-side rotor configuration 32 when the axis of rotor
tilt 20 is in the side-by-side position 30 and the first and second
axes of rotation 24, 26 of the first and second rotors 14, 16 are
oriented in a vertical position 34. When the air vehicle is in the
side-by-side rotor configuration 32, the plane defined by the first
and second axes of rotation 24, 26 of the first and second rotors
14, 16 is generally normal to the longitudinal axis 8. The air
vehicle can fly as a rotary wing aircraft when the air module 2 is
in the side-by-side rotor configuration 32 and when the air module
2 is translating between the tandem rotor configuration 18 and the
side-by-side rotor configuration 32.
[0105] The third flight configuration is the tilted-rotor
configuration 38 shown by FIG. 3. The air vehicle is in the
tilted-rotor configuration 38 when the axis of rotor tilt 20 is in
the side-by-side position 30 and the first and second rotor axes of
rotation 24, 16 are in the horizontal position 36, all as shown by
FIG. 3. When the first and second rotors 14, 16 are in the
tilted-rotor configuration 38, the plane defined by the first and
second axes of rotation 24, 26 is generally parallel to the
longitudinal axis 8.
[0106] In the tilted-rotor configuration 38, the air module 2 flies
as a fixed-wing aircraft with the rotors 14, 16 acting as
propellers urging the air module 2 through the air. To fly as a
fixed-wing aircraft, the air module 2 must have a wing 40, as
described below relating to FIGS. 5, 6, 8, and 9 through 11.
[0107] B. Modular two Rotor Ducted Fan Embodiment
[0108] FIGS. 4 through 8 illustrate a twin rotor ducted fan
embodiment of the air module 2. As shown by FIGS. 4 through 8,
first rotor 14 may be surrounded by a first circular duct 42 and
second rotor 16 may be surrounded by a second circular duct 44 to
form a first ducted fan 46 and a second ducted fan 48. The use of
ducted fans 46, 48 allows the first rotor 14 and second rotor 16 to
generate more thrust for a given rotor 14, 16 diameter than
otherwise would be possible. The first and second circular ducts
42, 44 also serve to protect rotors 14, 16 from damage.
[0109] In each embodiment and all configurations, a central unit 50
houses the engine(s) to power the rotors 14, 16. The central unit
50 houses the engine(s), drive system for the two ducted fans 46,
48, starter batteries, flight avionics, optional sensors,
communications relays and autopilot control system.
[0110] In the tilted-rotor configuration 38 illustrated by FIGS. 5,
6 and 8, the first circular duct 46 acts as a first circular wing
52 and the second circular duct 48 acts as a second circular wing
54. Circular wings 52 and 54 provide lift to the air module 2 to
support the air module 2 in the air when the air module 2 is in the
tilted-rotor configuration 38 and is moving in the direction of the
longitudinal axis 8.
[0111] As shown by FIGS. 5, 6, and 8, a first wing extension 56 may
be attached to an outside 58 of the first circular duct 42 and a
second wing extension 60 may be attached to an outside 62 of the
second circular duct 44. The first and second wing extensions 56,
60 provide additional lift to support the air module 2 in the air
when the air module 2 is in the tilted-rotor configuration 38. The
first and second wing extensions 56, 60 may fold about a hinge 64
between a deployed position (shown by FIGS. 5, 6 and 8) and a
retracted position (shown by FIG. 7) to reduce the size of the air
module 2 when the first and second wing extensions 56, 60 are not
in use. The first and second wing extensions 56, 60 may be arcuate
in shape and may conform to the periphery 66 of the circular ducts
42, 44 for compact size in the retracted position.
[0112] FIGS. 4 through 8 also illustrate the modular nature of the
air vehicle. FIGS. 4 and 5 illustrate an air module 2 in flight
without a ground module 6 attached. In FIG. 4, the air module 2 is
flying as a rotary wing aircraft. The air module 2 is supported by
lift generated by the first and second rotors 14, 16 acting as
rotary wings 4.
[0113] FIG. 5 illustrates the air module 2 flying in the
tilted-rotor configuration 38 without a ground module 6 attached,
with wings 40 providing lift to support the air module 2. First and
second rotors 14, 16 act as propellers to urge the air module 2
through the air.
[0114] FIGS. 6 and 8 illustrate the air module 2 flying in the
tilted-rotor configuration 38 with a ground module 6 attached, with
the circular wings 52,54 and wing extensions 56, 60 providing lift
to support the air module 2 and ground module 6. The air module 2
also may support the ground module 6 in flight in the tandem rotor
configuration 18 and the side-by-side rotor configuration 32, with
the first and second rotors 14, 16 acting as rotary wings 4 to
provide the required lift.
[0115] FIG. 7 illustrates the air module 2 attached to a ground
module 6 in the tandem rotor configuration 18 while on the ground
74, with the ground module 6 supporting the air module 2 above the
ground 74.
[0116] C. Two Open Rotor Embodiment
[0117] An open rotor 66 embodiment of the air module 2 having two
rotors 14, 16 and three rotor configurations is illustrated by
FIGS. 9 through 11. The open rotor 66 embodiment dispenses with the
circular ducts 42, 44 of the ducted fan 46, 48 embodiment. The
first and second rotors 14, 16 may move through the same three
rotor configurations 18, 32, 38 as the ducted fan 46, 48 embodiment
of FIGS. 4 through 8. FIG. 9 illustrates the open rotor 66 air
module 2 in the tandem rotor configuration 18. FIG. 10 illustrates
the open rotor air module 2 in the side-by-side rotor configuration
32. FIG. 11 illustrates the open rotor air module 2 in the
tilted-rotor configuration 38. The open rotor 66 embodiment
operates in the same manner as the twin ducted fan embodiment
discussed above, except as follows.
[0118] The open rotor 66 embodiment does not feature circular ducts
44, 46 and hence does not have circular wings 52, 54. Instead, the
open rotor 66 embodiment has a tilt wing 68 with a chord oriented
generally parallel to the first and second rotor axes of rotation
24, 26. When the air module 2 is flying in the tandem rotor
configuration 18 shown by FIG. 9 or the side-by-side rotor
configuration 42 shown by FIG. 10, the vertical orientation of the
chord of the tilt wing 68 reduces downwash effects from the rotors
14, 16 against tilt wing 68. When the air module 2 is transitioning
to the tilted-rotor configuration 38 illustrated by FIG. 11, the
tilt wing 68 tilts about the axis of rotor tilt 20 so that the
chord of the tilt wing 68 is parallel to the longitudinal axis 8.
In the tilted-rotor configuration 38, the tilt wing 68 provides
lift to support the air module 2 and the ground module 6 in the
air.
[0119] The tilt wing 68 may be provided with a first wing extension
56 and a second wing extension 60. The first and second wing
extension 56, 60 may fold about hinge 64 to the retracted position
to reduce the size of the air module 2 when the wing extensions 56,
60 are not in use, as illustrated by FIGS. 9 and 10. The wing
extensions 56, 60 may be extended to the deployed position,
illustrated by FIG. 11, extending the span and wing area of tilt
wing 68 to provide additional lift to the air module 2 when the air
module 2 is in the tilted-rotor configuration 38.
[0120] Rotors 14, 16 for both the twin open rotor 66 embodiment and
the twin ducted fan embodiment may be tilted to either side of
vertical when the rotors 14, 16 are in the tandem rotor position 18
and the side-by-side rotor configuration 32 to provide active
center of gravity (CG) control. In this configuration, the tilt of
the rotors is the CG actuator illustrated by FIG. 21.
[0121] The open rotor air module 2 may dispense with the tilt wing
68, and hence with the tilted-rotor configuration 18, in which case
the air module 2 may fly as a rotary wing aircraft in only the
tandem rotor configuration 18 or the side-by-side rotor
configuration 32. The air module 2 having two open rotors 68 also
may operate in positions intermediate to the tandem rotor and
side-by-side rotor configurations 18, 32.
[0122] D. Ground Module
[0123] The air module 2, whether ducted fan or open rotor, may
support an attached ground module 6 in flight. When the ground and
air modules 6, 2 are attached and on the ground 74, the ground
module 6 may support the air module 2, as shown by FIG. 8. A ground
module 6 may include a crew cabin 76 and be configured to
accommodate one or more human beings. For ground modules 6 that are
so configured, the unmanned air module 2 will support the attached
ground module 6 and its human occupants in flight.
[0124] The ground module 6 may be a vehicle ground module 70, as
illustrated by FIGS. 6, 7 and 8 through 11. The vehicle ground
module 70 is configured to move under its own power across the
surface of the ground 74 either with the air module 2 attached or
separately from the air module 2. The vehicle ground module 70 is
configured to contain one or more human beings, such as one or more
soldiers, and their equipment in a crew cabin 76 while it moves
across the ground 74. The vehicle ground module 70 includes wheels
72 that support the vehicle ground module 70 on the surface of the
ground 74. The vehicle ground module 70 include one or more motors,
such as one or more electric motors, to turn one or more of the
wheels 72 and also includes batteries to power the motors. The
vehicle ground module 70 may move across the ground under battery
power alone. The vehicle ground module 70 may include an internal
combustion engine and associated electrical generating system to
extend the range of the vehicle ground module 70. Alternatively, a
conventional internal combustion engine may drive one or more
wheels 72 directly through a conventional transmission or
transaxle. Any conventional system known in the automotive art to
drive one or more wheels 72 of the vehicle ground module 70 is
contemplated by the invention.
[0125] The vehicle ground module 6 shares a separable fuel system
with the air module 2 and the fuel stored on either the air module
2 or the vehicle ground module 70 may be used to supply the other.
The vehicle ground module 70 also shares a separable electrical
system with the air module 2 and the air module turbine engine(s)
90 can supply supplemental electrical power to the vehicle ground
module wheels 74. The air module 2 electrical power can be used to
provide directional control to the ground module 6 by applying
differential power to the ground module 6 wheels, resulting in skid
steering.
[0126] When the vehicle ground module 70 and air module 2 are
engaged, the electrical power systems of the two modules 70, 2 are
joined. Electrical power generated by the engines 90 of the air
module 2 may be used to charge batteries of the vehicle ground
module 70, drive the wheels 74 of the vehicle ground module or
start the engine of the vehicle ground module 70. Conversely, the
batteries or engine of the vehicle ground module 70 may power the
starting of the engines 90 of the air module 2.
[0127] From FIG. 8, the ground module 6 may be a medical module 20
and may be configured to contain one or more human patients, such
as wounded soldiers on a battlefield, and one or more human
attendants. The medical module 20 may be equipped with systems to
treat and sustain the one or more patients until the air module 2
delivers the medical module 20 and the patients to a care
facility.
[0128] Also from FIG. 8, the ground module 6 may be a cargo module
22 configured to transport any desired cargo through the air. The
ground module 22 may be a weapons module 24 configured so that the
air module 2 and weapons module 24 in combination provide a
remotely operated aerial weapon. The weapons module 24 may include
conventional communications and targeting systems to allow a remote
operator, such as a soldier in a vehicle ground module 20, to
select a target on the ground 74 and to destroy the target using
the air module 2 and weapons module 24 combination. The weapons
module 24 may include a supplemental fuel supply to allow the air
module 2 and weapons module 24 combination an extended loiter time
over a target area. The ground module may be a passenger module
configured to carry human passengers or may be a communications
module equipped to accommodate communications systems.
[0129] E. Two Rotor Embodiment Having Monocyclic Pitch and Torsion
Beams
[0130] The two rotor embodiments capable of transition among the
tandem rotor configuration 18, the side-by-side rotor configuration
32 and the tilted-rotor configuration 38 must provide control in
the yaw, pitch and roll axes for all three configurations 18, 32,
38. Control in all three axes in all three configurations is
achieved by providing the first and second rotor 14, 16 with
monocyclic pitch in a direction normal to the axis or rotor tilt 20
and by mounting the rotors 14, 16 on flexible torsion beams 86, 88,
all as shown by FIGS. 12 through 14.
[0131] FIG. 12 illustrates how pitch control is applied to a blade
94 of a rotor 14, 16. FIG. 12 shows a ducted fan embodiment, but
the explanation applies equally to open rotor embodiments. First
rotor 14 features a first circular duct 42 and a rotor blade 94.
Rotor blade 94 is attached to a hub 96 with a pivoting blade mount
and rotates about the first rotor axis of rotation 24. The pitch of
blade 94 can vary as the blade rotates about the hub 96. Blade 94
pitch is determined by a first swashplate 98 that rotates with the
blade 94. The swashplate 98 is capable of being tilted at a
swashplate angle 104 as it rotates. A pitch link 100 between the
swash plate 98 and the blade 94 translates the changing angle 104
of the swashplate 98 as it rotates into a changing pitch of the
rotating blade 94. For monocyclic pitch control, two control input
pushrods 102 determine the swashplate angle 104 so that the change
in blade 94 pitch caused by the swashplate angle 104 is greatest
when the blade 94 is farthest away from the axis of rotor tilt 20
during the rotation of the blade 94 and the change in blade 94
pitch caused by the swashplate angle 104 is substantially zero when
the blade 94 is parallel to the axis of rotor tilt 20. For
monocyclic pitch control, the change in blade 94 pitch caused by
the swashplate 98 tilt applies a torque to the hub 96 and hence to
the rotor 14, 16 parallel to the axis of rotor tilt 20.
[0132] The hub 96 is attached to the central unit 50 of the air
module 2 by the first flexible torsion beam 86. The torque applied
to the hub 96 applies a pre-determined torsion load to the first
flexible torsion beam 86, which has a pre-determined resilience in
torsion, causing a pre-determined angular deformation of the first
flexible torsion beam 86. The angular deformation of the first
flexible torsion beam 86 causes a pre-determined change in the
angle of tilt of the rotor axis of rotation 24, 26 about the rotor
tilt axis 20. The change in the tilt of the rotor axis of rotation
24, 26 changes the direction of thrust of the rotor 14, applying a
pre-determined yaw or roll moment to the aircraft.
[0133] The second rotor 16 has a second swashplate 110 that
determines a second monocyclic pitch of the second rotor 16. The
second rotor 16 operates in the same manner as the first rotor 14.
The monocyclic pitch of the second rotor 16 applies a predetermined
second torsion load to the second flexible torsion beam 88, causing
a predetermined angular deformation of the second flexible torsion
beam 88 and a pre-determined change in the direction of thrust of
the rotor 16. The first and second rotors 14, 16 cooperate to apply
a predetermined yaw or rolling moment to the aircraft.
[0134] FIGS. 13 and 14 illustrate the application of the effects
described above relating to FIG. 12. As described above, rotors 14,
16 are rigid, meaning that the rotor blades do not flap, lead or
lag. FIG. 13 shows the ground module 6 and air module 2 in the
side-by-side rotor configuration 32. Ground module 6 is attached to
air module 2. Engines 90 generate power that is transmitted to
rotors 14, 16. Rotors 14, 16 and ground module 6 are supported with
respect to each other by flexible torsion beams 86, 88, which are
resiliently flexible in torsion. When differential monocyclic pitch
is applied to rotors 14, 16, the rotors 14, 16 apply torsion to the
torsion beams 88. Torsion of the torsion beams 86, 88 allows the
rotors 14, 16 and circular ducts 42, 44 to deflect differentially,
so that the first and second rotor axes of rotation 24, 26 move
within a degree of freedom shown by arrows 106. The deflection of
the torsion beams 86, 88 tilts the rotors 14, 16 in opposite
directions, applying a yawing moment to the air module 2 and ground
module 6 combination, controlling yaw.
[0135] When non-differential cyclic pitch is applied to both rotors
14, 16, the torque applied to the torsion beams 86, 88 assists in
moving the rotors 14, 16 from the side-by-side configuration 32 to
the tilted-rotor configuration 38, allowing smaller and lighter
control effectors to be used for that task
[0136] FIG. 14 shows the ground module 6 and air module 2 in the
tilted-rotor configuration 38. Differential monocyclic pitch
applied to rotors 2 applies torsion to flexible torsion beams 86,
88, which allow the rotors 14, 16 to tilt in the direction
indicated by arrows 108. The differential tilt of the rotors 2
applies a rolling moment to the ground module 6 and air module 2
combination, controlling roll.
[0137] F. Two or More Air Modules Acting in Cooperation
[0138] Two or more air modules 2 may be joined together to lift and
transport loads, that are too heavy or too large for a single air
module 2, as illustrated by FIGS. 15 through 19.
[0139] Two or more air modules 2 may be attached to a single ground
module 6 so that the ground module 6 becomes the physical
connection between the air modules 2. The air modules 2 may fly
independently to the ground module 6, join to the ground module 6,
and lift the ground module 6 as a single aircraft comprising the
two air modules 2 and the ground module 6. In two or more air
module 2 configurations, the control systems of the air modules 2
are operably joined so that the two or more air modules 2 operate
as a single aircraft when supporting the ground module 6.
[0140] FIGS. 15 through 18 illustrate a two-air module 2 embodiment
in which two air modules 2 are attached to a single ground module 6
and the ground module 6 provides the physical connection between
the air modules 2. FIGS. 15 and 17 are plan views of a two-air
modules 2 embodiment. FIG. 16 is a side view of the two-air modules
2 embodiment and FIG. 18 is a perspective view. In FIG. 15, the air
modules 2 are in the second, or side-by-side configuration.
[0141] In FIGS. 16 and 17, the air modules 2 are in the tandem
rotor configuration 18. In FIG. 18, the air modules 2 are in the
tilted-rotor configuration 38. Air modules 2 may move between the
tandem rotor configuration 18, the side-by-side rotor configuration
32 and the tilted-rotor configuration 38 for the two or more air
modules 2 configuration, just as a single air module 2 aircraft may
move between configurations. FIGS. 15-19 illustrate the ducted
rotors 14, 16, engines 90, wing 40, wing extensions 56, 60, and
flexible torsion beams 86, 88, and central units 50.
[0142] As shown by FIG. 19, two or more air modules 2 may be joined
by a scaffold 108, such as a spar or frame, and the load to be
lifted may be rigged to the scaffold 108. When joined by a scaffold
108, the air modules 2 may fly to the load to be lifted as a single
aircraft. As shown by FIG. 19, the two air modules 2 joined by the
scaffold 108 flies autonomously as a single aircraft, with the two
air modules 2 acting in cooperation.
[0143] The embodiments illustrated by FIGS. 18 and 19 provide that
the two or more air modules 2 are in close proximity and that the
first (tandem) rotor configuration 18 is not possible due to
interference between the rotors 14, 16. In such an embodiment, the
air modules 2 may be configured so that the air modules 2
transition only between the side-by-side rotor configuration 32 and
the tilted-rotor configuration 38. The air modules 2 may be
configured so that the two or more air modules 2 operate only in
the side by side rotor configuration 32 when lifting of a very
heavy load is desired. In such a configuration, the lifting
capacity is modular. If two air module 2 will not be adequate to
support the load, then a third can be added. The number of air
modules 2 that can be applied to a load is limited only by the
dimensions of the scaffold 108 or the ground module 6.
[0144] G. Dynamic Center of Gravity Control.
[0145] FIGS. 20 through 26 address dynamic center of gravity
control. The pilot of a conventional aircraft must be aware of the
center of gravity ('CG') of the aircraft to preserve the flight
characteristics of the aircraft. If the CG of an aircraft moves,
such as by loading or distribution of passengers, fuel or cargo
within the aircraft, then changes in the aircraft attitude will
occur that must be corrected by the pilot or control system. The
air module 2 and ground module 6 combination may be equipped with
dynamic CG control in one, two or three dimensions to allow the
aircraft to automatically respond to changes in CG during
flight.
[0146] The control system for active dynamic CG control is
illustrated by FIG. 20. The active dynamic CG control comprises one
or more sensors 112 to detect a change or rate of change of
attitude of the aircraft and to detect a deviation from the
commanded attitude. The CG sensors 112 are configured to determine
the deviation of the CG from an optimum CG location or envelope,
which may be defined in one, two or three dimensions. The automatic
control system generates a CG correction signal 114 to command
corrections in the CG, and actuators 116 to adjust the relative
locations of the CG and the center of lift of the aircraft when the
aircraft is in flight.
[0147] To align the center of gravity with the center of lift, the
dynamic CG control system 114 may move the center of gravity of the
ground module 6 and air module 2 combination, may move the center
of lift of the air module, or may move both.
[0148] FIGS. 21 through 26 illustrate different embodiments that
move the center of gravity of the ground module 6 with respect to
the center of lift of the air module 2 to achieve dynamic CG
control.
[0149] The CG control may be active or passive. FIG. 21 illustrates
passive CG control. Passive CG control may be as simple as hanging
the ground module 6 from the air module 2 by a link 116 that is
free to move in one or two dimensions. Damping may be provided to a
passive dynamic CG control system to prevent unwanted oscillations.
Two ball joints 118 connect the link to the air module 2 and the
ground module 6 for passive CG control in two dimensions. As the
center of gravity of the ground module 6 changes, the link 116
moves within sockets 120, automatically compensating for the change
in CG without intervention from the control system.
[0150] Because of the two spaced-apart rotors, the air module and
the air module/ground module combination has a great deal of
control power along the rotor axes of rotation 24, 26; that is, in
roll when the aircraft is in the side-by- side rotor configuration
32 and in pitch when the aircraft is in the tandem rotor
configuration 18. The air module 2 and ground module 6 combination
has relatively low control power in the direction normal to the
rotor axes of rotation 24, 26; that is, in pitch when the aircraft
is in the side-by-side rotor configuration 38 and in roll when the
aircraft is in the tandem rotor configuration 18. Dynamic CG
control therefore is most important in the dimension normal to the
rotor axes of rotation 24, 26.
[0151] FIG. 22 illustrates an active dynamic CG control one
dimension. A pinned link 122 connects the air module 2 and the
ground module 6. The pinned link 122 is capable of movement in one
dimension only. A screw jack or hydraulic jack 124 receives a CG
correction signal from the CG control system 114 and moves the
pinned link 122 to a location determined by the CG control system
114, controlling CG in one dimension.
[0152] FIG. 23 illustrates a combination active and passive dynamic
CG control in three dimensions. A flexible fabric strap 126, such
as Kevlar.RTM., is attached to the ground module 6. The other end
of strap 126 is supported by actuator 128. Actuator 128 is a screw
or hydraulic jack and is movable in the vertical direction; that
is, in the direction parallel to the axes of rotation of rotors 14,
16 when the rotors are in the vertical position 34. Actuator 128
therefore can move strap 126 in the vertical direction. Strap 126
swings freely below air module 2 and therefore automatically
adjusts CG of the aircraft in two dimensions. CG control is active
in the third dimension.
[0153] FIGS. 24 and 25 illustrate an active dynamic CG control in
three dimensions. FIG. 24 is a detail side view. FIG. 25 is a
detail cutaway top view. First crank 130 is rotatably attached to
ground module 6 and is movable in the direction indicated by arrow
131. The location of first crank 130 is adjusted by first actuator
133. A second crank 132 is rotatably attached to first crank 130
and is movable in the direction indicated by arrow 134. Second
crank 132 also is rotatably attached to vertical shaft 136. The
location of second crank 132 is adjusted with respect to first
crank 130 by second actuator 135. CG therefore is adjustable in two
dimensions by the operation of first and second actuators 130, 132.
Vertical shaft 136 is adjustable in the vertical dimension,
indicated by arrow 138, by the operation of third actuator 140,
thereby adjusting CG in the third dimension. First, second and
third actuators 130, 132, 140 may be screw jacks or hydraulic
cylinders.
[0154] Active dynamic CG in three dimensions also is illustrated by
FIG. 26. First cross slide 142 engages ground module 6 when the air
and ground modules 2, 6 are in engagement. First cross slide 142
engages second cross slide 144 so that first cross slide 142 is
constrained to move in the direction indicated by arrow 143 of FIG.
27 with respect to second cross slide 144. First actuator 145 moves
first cross slide 142 with respect to second cross slide 144.
Second cross slide 144 also engages cross slide base 146 so that
second cross slide 144 is constrained to move in the direction
indicated by arrow 147 with respect to cross slide base 146. Second
actuator 148 moves second cross slide 144 with respect to cross
slide base 146. Cross slide base 146 is attached to column 150.
Column 150 constrains the motion of cross slide base 146, and hence
ground module 6, with respect to air module 2. Third actuator 151
moves cross slide base 146 in the vertical direction indicated by
arrow 152 with respect to air module 2. Ground module 6 therefore
is movable in three dimensions with respect to air module 2.
[0155] The active dynamic CG control can used to assist in the
directional control of the aircraft, such as for lateral
translation. The rotors 14, 16 do not have full cyclic pitch and
have limited control power normal to the axis of rotor tilt 20 of
the air module 2. The active dynamic CG control may be used to tilt
the aircraft and hence to move the aircraft in the direction normal
to the axis of rotor tilt 20. Dynamic CG control also may be used
to assist in dynamic flight operations, such as attitude control to
assist the aircraft in turning or in slowing the forward motion of
the aircraft. In this mode, active CG control functions in a manner
similar to weight-shift control systems employed by hang gliders,
but without operator awareness or intervention as is required by
hang gliders.
[0156] Changes to the center of gravity of the aircraft may be
coupled with changes to the center of lift. Active CG control
provides redundant control to collective pitch control, cyclic
pitch control, rotor tilt and exit vane 154 control to control the
attitude and flight of the aircraft.
[0157] H. Ducted Fan Embodiment Equipped with Exit Vanes
[0158] As shown by FIG. 7, the air module 2 may be equipped with
one or more movable exit vanes 154 oriented parallel to the axis of
rotor tilt 20. First exit vane 154 is located on the downstream
side of the first ducted fan 46 in the exhaust of first ducted fan
46. The second exit vane 154 is located on the downstream side of
the second ducted fan 48 and is located in the exhaust of the
second ducted fan 48. First and second exit vanes 154 each may tilt
about a longitudinal axis, which is oriented parallel to the axis
of rotor tilt 20, to define an exit vane angle. The exhaust air
from the ducted fans 46, 48 blows across the exit vanes 154,
creating a reaction force on each vane 154 that is adjustable by
adjusting the exit vane angle with respect to the flow of exhaust
air.
[0159] The first and second exit vanes 154 provide control that is
redundant to the monocyclic pitch control, providing the control
system with additional control solutions to achieve a desired
flight condition and providing additional control power in the
direction normal to the axes of rotation 24, 26 of the first and
second rotors 14, 16.
[0160] I. Ballistic Parachute and Airbag
[0161] Battle damage, human error or component failure may cause
the air module 2 to cease operating within design parameters. The
air module 2 or the ground module 6 may include a ballistic
parachute and airbag to protect the ground module 6 and its
occupants in the event of battle damage, human error or component
failure.
[0162] The conventional ballistic parachute 156 is shown by FIG.
27. The ballistic parachute 156 includes a pneumatic parachute
mortar 158 mounted to the air module 2 or ground module 6. When the
control system detects an aircraft condition outside of
predetermine parameters, the control system automatically fires the
mortar 158, deploying the ballistic parachute 156, lowering the
ground module 6 and its occupants and cargo to the ground 74.
[0163] The control system may constantly monitor motion and
attitude of the air module 2, and directs a mortar pointing system
to aim the mortar 158 in a direction that provides optimum
deployment and inflation of the parachute 156. An example is
directing the mortar 158 ahead of the air module 2 to provide a
vector for the parachute 156 that will accommodate aircraft forward
motion and prevent the parachute 156 from opening behind the
aircraft. The parachute 156 may be deployed by a steerable rocket
to achieve the same end.
[0164] It is anticipated that the ballistic parachute 156 will
reduce the velocity of the air module 2 and ground module 6
combination to 12 feet per second. It is further anticipated that
the speed of descent is further reduced to 6 feet per second by air
bag 160. The long-travel, energy-absorbing landing gear 162 of the
ground module 6 can absorb the remaining impact, protecting the
occupants of the ground module 6.
[0165] As shown by FIG. 26, the airbag 160 is located on the bottom
side 164 of ground module 6. Operation of the airbag 160 is
conventional and the airbag 160 is deployed either before or during
impact between the ground module 6 and the ground 74, as detected
by accelerometers.
[0166] J. Air Module Control System
[0167] The control system 166 of the unmanned air module 2 is
illustrated by FIGS. 29 through 31. From FIG. 29, the control
system 166 includes a microprocessor 168 operably connected to a
computer memory 170. A power supply 172 powers the control system
166. A control interface, which may be a port 174, a radio
transceiver 176, or both, allows communication with and programming
of the control system 166.
[0168] The control system 166 includes a variety of sensors 178
that are operably connected to the microprocessor. The sensors 178
include flight condition sensors 180, such as attitude, airspeed,
temperature, altitude, and rate sensors measuring changes to the
measured flight conditions. Control surface position sensors 180
detect the position of the various flight controls, such as
collective and cyclic pitch of each rotor 14, 16, rotor tilt axis
20 location, rotor tilt for each rotor, wing extension deployment,
active CG control position, vectored thrust orientation, and any
other control information that is determined to be useful. The
engine parameter sensors 182 inform the microprocessor of matters
relating to power, such as fuel reserves and consumption, engine
power, temperature of key components, throttle position, vibration
and additional engine power available. Navigation sensors 184
inform the microprocessor of the location of the air module 2 in
space and include sensors such as global positioning system
receivers and terrain and obstacle detecting sensors such as RADAR
and LIDAR transmitters and receivers.
[0169] The microprocessor 168 is configured to actuate several
effectors 186 to operate the flight controls of the air module 2,
including cyclic and collective pitch effectors for each rotor 14,
16, engine throttle control, effectors to change the location of
the axis of rotor tilt 20, effectors to tilt the rotors 14, 16,
active CG control effectors, effectors to deploy and retract wing
extensions 56, 60, effectors to deploy a ballistic parachute 156,
and engine 90 exhaust vectoring effectors.
[0170] The microprocessor 168 is programmed to receive commands
through the control interfaces 174, 176. The commands may include
specification of a mission plan, a specified landing zone and
waypoints between a starting location of the air module 2 and the
specified landing zone. The microprocessor 168 is configured to
operate as a conventional autopilot to fly the air module 2 on the
route specified by the mission plan, to pass through the specified
waypoints and to land at the specified landing zone, all without
human intervention.
[0171] The control system 166 may receive command while in flight
through the radio transceiver 176 to change the mission plan,
waypoints or landing zone. The radio transceiver may receive the
commands from a human operator at a remote location or from the
ground module 6 when the air module 2 and ground module 6 are
detached. When the air module 2 and ground module 6 are attached,
the ground module 6 may communicate with the control system 166
through port 174. A human occupant of the ground module 6 may
command changes to the mission plan, waypoints or landing zone.
[0172] FIGS. 30 and 31 illustrate operation of the autopilot air
module control system 166. The control mixer is an open-loop system
that determines the actuator commands for all control effectors 186
on the aircraft as a static function of the primary flight control
inputs and the control mode is determined by airspeed and the
current duct tilt. The four primary control inputs to the mixer are
the lateral, longitudinal, thrust and yaw controls. The control
effectors 186 include symmetric and differential duct tilt,
symmetric and differential cyclic pitch, symmetric and differential
collective pitch, engine throttle, and cruise flight pitch
stabilization using thrust vectoring of engine exhaust. Control
mixing can sometimes be achieved using a mechanical system, but for
a fly-by-wire configuration the mixing can be programmed for
implementation by the microprocessor 168. The latter approach
provides greater flexibility and more readily accommodates
modifications and upgrades. Control mixing achieves the control
modes to control roll, pitch, yaw and thrust in all flight
configuration 18, 32, 38 and during transition between
configurations. In transition between the low speed tandem rotor
configuration 18, the low speed side-by-side configuration 32, and
the high speed tilted-rotor configuration 38, the controls will be
blended smoothly between the modes.
[0173] The inner loop flight controls use a dynamic inversion
scheme since the stability and control characteristics vary
significantly in the various configurations 18, 32, 38. The
inversion model can be scheduled as a function of the duct tilt,
airspeed, and configuration parameters to provide consistent and
predictable response characteristics across the flight envelope and
configuration space.
[0174] In hover, tandem rotor configuration 18, and side-by-side
rotor configuration 32, the controller will achieve attitude
command/attitude hold (ACAH) response type in roll and pitch, and
rate command/heading hold (RCHH) response in yaw. In tilted-rotor
configuration 38 the pitch and yaw axes will include turn
compensation modes, and the roll mode can either be a rate command
or attitude command system. The thrust control will be open loop in
the core inner loop flight controls.
[0175] The RPM governing systems on tilted-rotor aircraft are
particularly challenging since the RPM must be regulated in both
helicopter and cruise flight modes. Typically blade-pitch governing
systems are used on tilted-rotor aircraft as they are more
effective in airplane mode where the rotor torque is sensitive to
changes in airspeed. The control system 166 included blade-pitch
governing. The pilot's thrust or collective control is directly
tied to the engine throttle. The control mixing determines
collective pitch as a sum of the feed forward collective input and
a trimming signal from the RPM governor. The feed forward input
comes from the pilots' thrust input and the differential collective
input (tied to roll and yaw axes). The RPM governor trim signal is
based on proportional plus integral compensation on the rotor speed
error from the nominal.
[0176] When the air module 2 is piloted, either by a human occupant
of the ground module 6 or by a human operator at a remote location,
the outer loop control laws will achieve a translation rate command
response type in rotary wing flight, where the vehicle lateral and
longitudinal speed are proportional to pilot stick input. In the
thrust axis, the control will achieve vertical speed command/height
hold. Such a control law can allow operation in degraded visual
environments or high confined environments with reasonably low
pilot workload. Upon the pilot releasing the controls, the system
will revert to full autonomous control. In piloted tilted-rotor
configuration 38, the outer loop controls will feature airspeed and
altitude hold modes that can also be programmed through the
displays. The outer loop control laws can be tied to a basic way
point navigation system.
[0177] Unlike a conventional tilted-rotor aircraft, symmetric and
differential duct tilt of the air module 2 will be part of the
inner loop primary flight control for the pitch, roll and yaw axes.
The use of cyclic pitch on the rotors will be used to twist the
ducts differentially through a flexible torsion beam 86, 88 and
will reduce the actuation requirements for duct tilt during
conversion to tilted-rotor configuration 38. A stiff rotor system
14, 16 will be used, so significant hub 96 moments can be achieved
by cyclic pitch. If engines 90 are selected having high exhaust gas
flow rates, the exhaust gas can be vectors to provide additional
control in pitch when the air module 2 is in the tilted-rotor
configuration 38.
[0178] K. Alternate Rotor Configurations
[0179] FIGS. 32 through 34 illustrate alternate configurations that
rotary wing 4 may take. FIG. 32 illustrates a single ducted fan or
single open rotor 188 embodiment of the air module 2. A single
rotor 14 is powered by the central unit 50. A propeller 190 mounted
on a boom 192 reacts the torque of the single rotor 188 to control
yaw. The single rotor 188 embodiment is modular and the air module
2 and ground modules 6 may be operated independently; however, the
air module 2 and the air module 2 and ground module 6 combination
may fly in only one configuration as a rotary wing aircraft.
[0180] FIG. 33 illustrates a coaxial open rotor 194 embodiment of
the air module 2. Two counter-rotating coaxial rotors 14, 16 are
powered by the central unit 50. Because of the counter-rotating
rotors 14, 16, the torque reaction of each rotor cancels that of
the other and no boom 192 or propeller 190 is required. The coaxial
open rotor 194 embodiment otherwise is similar to the single open
rotor 188 embodiment of FIG. 32 and may fly in only one
configuration as a rotary wing aircraft.
[0181] In each of FIGS. 32 through 34, the air module 2 and ground
module 6 are modular and may be detached and each may operate
independently of the other. The air module 2 may take off, fly and
land independently from the ground module 6. Where the ground
module 6 is a vehicle ground module 70, the vehicle ground module
70 may operate on the ground 74 under its own power independent of
the air module 2. The air module 2 and ground module 6 may be
joined selectably so that the air module 2 supports the ground
module 6 in flight and the ground module 6 supports the air module
2 when on the ground.
[0182] FIG. 34 illustrates an autogyro air module 196 embodiment.
The engine 90 in central unit 50 powers a vectored thruster 198,
such as a propeller or ducted fan. The vectored thruster 198 is
shown by FIG. 35 as a pusher propeller on boom 200, but the
vectored thruster 198 may be a tractor propeller and may be mounted
to ground module 6. The vectored thruster 198 provides forward
thrust to the air module 2 and ground module 6 combination. Air
moving from the underside of the spinning rotor disc to the top
side of the rotor disc causes the rotor 14 to keep rotating,
generating lift and maintaining the air module land ground module 6
combination airborne.
[0183] Any of the embodiments may be equipped with a propeller or
other vectored thruster 198 to provide forward thrust in addition
to thrust from the open rotor 188 or the ducted fan 46, 48.
[0184] The autogyro air module 196 may be a `jump` autogyro. For
takeoff, the rotor 14 is connected to the engine 90 and rotor 14 is
turned by the engine, storing kinetic energy in the rotor 14. The
rotor 14 is disconnected from the engine 90, the collective pitch
of the rotor blades 94 is increased, causing the rotor 14 to
generate lift, and the engine 90 is connected to the vectored
thruster 198. The air module 2 rises vertically and is driven
forward by the vectored thruster 198. When the aircraft reaches an
adequate forward speed, the air moving through the rotor 14 is
adequate to maintain the rotation of the rotor blade 94 and to
maintain flight. The autogyro air module 196 and ground module 6
are modular and operate in the same fashion as the ducted fan air
46, 48 module and the open rotor air module 188.
[0185] Air module 2 may be in any other configuration known in the
rotary wing 4 aircraft art, including a twin rotor aircraft having
intermeshing rotors and a tandem rotor aircraft that is not capable
of transitioning to the side-by-side rotor configuration 32 or the
tilted-rotor configuration 38. The air module 2 may have two rotors
in the side-by-side rotor configuration 32 that are not capable of
moving to the tandem rotor configuration 18 or the tilted-rotor
configuration 38. The air module 2 may be an aircraft that is
capable of flying in the side-by-side rotor configuration 32 and
the tilted-rotor configuration 38, but that is not capable of
flying in the tandem rotor configuration 32.
[0186] FIG. 35 illustrates a rotor mast 202 of the autogyro air
module 196. The rotor mast 202 incorporates both an extendable mast
204 for ground obstacle avoidance and a tiltable rotor mast for
active center of gravity (CG) control. Rotor 14 is attached to
autogyro rotor hub 206. Rotor 14 spins about center of rotation 24
of autogyro rotor hub 206. Mast 202 transmits lifting forces from
the rotor hub 206 to the central unit 50 of air module 2. Mast 202
comprises a first mast portion 208 and a second mast portion 210.
First and second mast portions 208, 210 are in a telescoping
relationship and may be keyed or splined to avoid rotation of the
first and second mast portions 208, 210 with respect to each other.
Alternatively, the first mast portion 208 may turn with the rotor
14 with respect to second mast portion 210 and may define the rotor
bearing allowing the rotor 14 to turn. Rotor extension screw jack
212 operates on rotor extension screw 214, which is attached to
first mast portion 208. The position of the rotor extension screw
determines the extended length of rotor mast 202.
[0187] Alternatively, rotor extension screw jack 212 and rotor
extension screw 214 may be dispensed with and the extension of the
autogyro rotor mast determined by the lift generated by the rotor
14. When the rotor 14 is spun by the engine 90 for takeoff, the
lift generated by the spinning rotor 14 extends the rotor mast 202.
When the aircraft lands and the rotor 14 slows, the rotor 14 loses
lift and the mast 202 moves from the extended to the retracted
position.
[0188] FIG. 35 also shows active CG control for the autogyro air
module 2 through tilting of rotor mast 202. Rotor mast 202 is
attached to central unit 50 through hinge 216. The nature of hinge
216 depends on the axes of active CG control. For one axis of CG
control, hinge 216 can be an axle and bearings supporting the axle.
For two axis CG control, hinge 216 can be a ball joint. For two
axis CG control, a second rotor tilt screw jack 218 is utilized for
control in the second axis. Rotor tilt screw jack 218 tilts rotor
mast 202 about hinge 216, and hence determines the location and
orientation of rotor lift with respect to the CG of the aircraft.
The rotor tilt screw jack 218 is the CG actuator attached to the CG
control system of FIG. 20.
[0189] FIG. 36 illustrates a rotor tilt active CG system for a open
rotor air module 2 that files as a helicopter and as illustrated by
FIGS. 9 through 11, 32 and 33. Screw jack 220 determines the tilt
of rotor mast 202. The rotor drive shaft 222, contained within
rotor mast 202, transfers power to rotor 14 through a flexible
coupling 224. The screw jack 220 is the CG actuator shown by FIG.
21 to move the center of lift of the air module 2 with respect to
the center of gravity.
[0190] FIGS. 37 and 38 illustrate an extendable rotor mast 202 for
an open rotor 188 air module 2 that flies as a helicopter and as
illustrated by FIGS. 9 through 11, 32 and 33. The extendable rotor
mast 202 allows the rotor 14 to have a lower profile for ground
transportation of the air module 2, but allows the rotor 14 to have
a higher configuration for safe ground operations when the rotor 14
is turning.
[0191] FIG. 37 illustrates the extendable rotor mast 202 in the
contracted (lower) position. Drive shaft 222 is turned by engine.
Drive shaft 222 is splined to rotor shaft 226, so that rotor shaft
226 may slidably move in a longitudinal direction with respect to
drive shaft 222 and so that drive shaft 222 transmits rotational
power to rotor shaft 226. Rotor shaft 226 turns rotor 14. Rotor
mast 202 includes a first rotor mast portion 228 and a second rotor
mast portion 230. First rotor mast portion 228 is attached to hub
96 and second rotor mast portion 230 is attached to central unit
50. First and second rotor mast portions 228, 230 are splined or
keyed one to the other and do not rotate with rotor 14. First and
second rotor mast portions 228, 230 maintain the stationary portion
of swashplate 98 within hub 96 in a stable position. First and
second rotor mast portions 228, 230 are movable with respect to
each other by rotor extension screw jack 232 and screw 234.
[0192] FIG. 38 shows the extended position of the extendable rotor
mast 202 of FIG. 38. Splined driveshaft 222 and rotor shaft 226
transmit power to turn rotor 14 while first and second mast
portions 228, 230 do not rotate and maintain swashplate in hub 96
in a stable, stationary condition.
[0193] Rotor extension screw jack 232 and screw 234 may be
dispensed with and lift generated by the rotor 14 may be used to
extend extendable rotor mast 202. Loss of lift from the slowing
rotor 14 after landing may automatically retract extended rotor
mast 202.
[0194] In this document, the term "screw jack" refers to screw
jacks and to any other conventional apparatus to transmit linear
motion, including a hydraulic cylinder and a rack and pinion.
[0195] The open rotor air modules of FIGS. 9 through 11, 32 and 33
may be configured to have a rotor 14 with extendable blades 236,
illustrated by FIGS. 39 through 42. FIG. 39 shows the extendable
blade 236 in the retracted position for ease of ground travel. FIG.
40 shows the extendable blade 236 in the extended position. The
extendable blades 236 are telescoping, as illustrated by FIGS. 40,
41 and 42.
[0196] FIGS. 41 and 42 are a cutaway plan views showing the
telescoped blades 236 in the retracted and the extended positions.
The telescoping blades 236 are illustrated have three sections,
236a, b and c, though extendable blades 236 with two sections or
with more than three sections are contemplated by the invention.
Blade extension screw jacks 238 and blade extension screws 240 move
the blades 236 between the extended and retracted positions.
* * * * *