U.S. patent application number 10/309828 was filed with the patent office on 2004-06-10 for survivable and reusable launch vehicle.
Invention is credited to August, Henry.
Application Number | 20040108410 10/309828 |
Document ID | / |
Family ID | 32392918 |
Filed Date | 2004-06-10 |
United States Patent
Application |
20040108410 |
Kind Code |
A1 |
August, Henry |
June 10, 2004 |
SURVIVABLE AND REUSABLE LAUNCH VEHICLE
Abstract
A reusable, mach-velocity mobile platform delivers a weapons
payload via vertical launch, powerless glide, weapons release, and
landing operation phases. The platform includes a generally tubular
shaped body having an aft and forward end, and a payload section.
An arch wing is supported by the body aft end. The arch wing has an
upper and a lower wing joined at distal ends by two curved end
plates. A nose assembly is connected at the forward end having an
upward directed fixed angle-of-attack to generate forward end lift.
Thermal tiles attached under the body and the lower wing under-side
radiate/dissipate heat generated during a high angle-of-attack
platform reentry. Radar absorptive or radar translucent material is
used. The platform preferably discharges payload from the aft end
for safe separation. A landing gear is extended for the landing
phase of operation.
Inventors: |
August, Henry; (Chatsworth,
CA) |
Correspondence
Address: |
HARNESS, DICKEY & PIERCE, P.L.C.
P.O. BOX 828
BLOOMFIELD HILLS
MI
48303
US
|
Family ID: |
32392918 |
Appl. No.: |
10/309828 |
Filed: |
December 4, 2002 |
Current U.S.
Class: |
244/2 |
Current CPC
Class: |
F42B 10/62 20130101;
B64C 2201/021 20130101; B64C 2201/104 20130101; B64C 39/024
20130101; B64C 2201/046 20130101; B64C 2201/121 20130101; F42B
12/58 20130101; F42B 15/00 20130101; F42B 10/16 20130101; F42B
12/62 20130101 |
Class at
Publication: |
244/002 |
International
Class: |
B64C 037/02; B64D
005/00 |
Claims
What is claimed is:
1. A reusable mobile platform comprising: a generally tubular
shaped body having an aft end, a forward end, and a payload
section; an arch wing supported at said aft end of said body; and a
nose assembly connected at said forward end, said nose assembly
having an upward fixed angle-of-attack to provide lift force at
said forward end; wherein said payload section is configurable to
support a weapons package for release from said aft end of said
package during a non-powered flight phase of said mobile
platform.
2. The mobile platform of claim 1, wherein said arch wing further
comprises: an upper wing having a continuous, generally planar
upper surface and a split, generally planar lower surface, said
split lower surface adapted to centrally support said upper wing
from said body; a lower wing having a modified planar/dihedral
shape including a lower surface and a split upper surface, said
split upper surface adapted to centrally support said lower wing
from said body; and a curved end-plate joining said upper wing to
said lower wing at opposed distal ends of both said upper wing and
said lower wing.
3. The mobile platform of claim 2, further comprising: said upper
wing and said curved end-plate formed of a radar translucent
material; said lower wing formed from one of a metal and a
composite material; and a radar absorbing material applied to
external facing surfaces of said lower wing.
4. The mobile platform of claim 3, wherein said upper wing further
comprises: an upper wing forward point disposed approximately
coincident with a body longitudinal axis extending along said
tubular shaped body; a swept wing angle measured from said upper
wing forward point to a forward facing point of each of said upper
wing distal ends.
5. The mobile platform of claim 4, wherein said lower wing further
comprises: a lower wing forward point disposed approximately
coincident with said body longitudinal axis and said swept wing
angle; and said swept wing angle measured from said lower wing
forward point to aforward facing point of each of said lower wing
distal ends; wherein said lower wing forward point is positioned
forward of said upper wing forward point such that said lower wing
shields said upper wing from elevated temperatures occurring when
said mobile platform operates at a reentry phase high
angle-of-attack.
6. The mobile platform of claim 5, wherein said lower wing, said
upper wing and said curved end plate further comprise: a generally
rounded leading edge; and a generally squared-off trailing
edge.
7. The mobile platform of claim 5, further comprising: said lower
wing having a starboard wing half and a port wing half; a pair of
elevons symmetrically spaced about said body longitudinal
centerline, one of said elevons disposed on each said split upper
surface of said starboard wing half and said port wing half; and a
pair of ailerons each positioned adjacent to one of said
elevons.
8. The mobile platform of claim 1, wherein said upward fixed
angle-of-attack of said nose assembly varies over a range of
approximately 4 degrees to approximately 15 degrees.
9. A reusable, mach-velocity mobile platform comprising: a
generally tubular shaped body having an aft end, a forward end, and
a payload section disposed about a longitudinal axis of said body;
an arch wing supported at said aft end of said body; a nose
assembly connected at said forward end, said nose assembly having
an upward fixed angle-of-attack to provide lift force at said
forward end; and a plurality of landing devices extendable from
said body; wherein said platform is adaptable for operation phases
including at least one of a propelled vertical launch phase, a
powerless glide phase, a weapons release phase, and a landing
phase.
10. The mobile platform of claim 9, further comprising: a payload
including one of an equipment package and a munitions package
stowable in said payload section; and a rear-release discharge face
to discharge said payload from said aft end of said body during
said weapons release phase.
11. The mobile platform of claim 9, wherein said mobile platform
further comprises a mobile platform center of gravity wherein said
arch wing is positioned aft of said mobile platform center of
gravity.
12. The mobile platform of claim 11, further comprising: a forward
steering device having independent starboard and port elements
extendable from said body; and a center of actuation positioned
forward of said mobile platform center of gravity such that
operation of said starboard and port elements induces a steering
force at said forward end of said body.
13. The mobile platform of claim 9, further comprising: said arch
wing including an upper wing and a lower wing; a plurality of heat
shields disposed on both an underside of said body and a lower
surface of said lower wing; said mobile platform operable in said
powerless glide phase at a reentry angle-of-attack having a range
of approximately 30 degrees to approximately 60 degrees measurable
from said body longitudinal axis; wherein said heat shields on said
lower wing during said powerless glide phase at said reentry
angle-of-attack to shield said upper wing.
14. The mobile platform of claim 9, further comprising a radar
absorbing material disposed about selected portions of said mobile
platform to reduce a radar cross section of said mobile
platform.
15. The mobile platform of claim 9, further comprising: said
forward steering device configurable as an arched wing canard; and
said arched wing canard having both a port adjustment mechanism and
a starboard adjustment mechanism to roll said mobile platform about
said mobile platform longitudinal axis; wherein said port
adjustment mechanism and said starboard adjustment mechanism each
additionally provide for independent port and starboard steering
forces for said mobile platform.
16. The mobile platform of claim 9, wherein said forward steering
device includes an expandable air flow opening such that as said
forward steering device extends away from said body, an air flow is
maintained between said forward steering device and said body.
17. The mobile platform of claim 9, further comprising: an
inflatable tail cone extendable from said aft end of said body; and
said inflatable tail cone having a rounded leading face and a
generally cone-shaped tapering body; wherein said inflatable tail
cone is extendable from said aft end of said body after said
powerless glide phase to reduce an aerodynamic drag of said mobile
platform and extend a range of said landing phase.
18. A method to operate a multiple mach velocity mobile platform
comprising the steps of: coating a plurality of body surfaces of a
mobile platform with a radar absorbing material; loading a weapons
package into said mobile platform; launching said mobile platform
to a predetermined altitude at a multiple mach velocity;
controlling a powerless flight phase of said mobile platform using
control surfaces mounted at both a forward end and an aft end of
said mobile platform; and discharging said weapons package through
an aft end of said mobile platform during a weapons release phase
following said powerless flight phase.
19. The method of claim 18, comprising reloading said mobile
platform following said powerless flight phase.
20. The method of claim 18, comprising extending a self contained
landing gear set during a landing phase following said powerless
flight phase and said weapons release phase.
21. The method of claim 18, comprising: coating a lower wing with
said radar absorbing material; forming an upper wing of a radar
translucent material; joining said lower wing to said upper wing
with a radar translucent curved plate pair to form an arched wing;
connecting said arched wing to said aft end; and controlling said
arched wing with both a set of elevons and a set of ailerons.
22. The method of claim 18, wherein said discharging step further
comprises dispensing said weapons package in multiple sub-phases to
each of a plurality of target areas.
23. The method of claim 18, comprising extending an inflatable tail
cone following said discharging step.
24. The method of claim 18, further comprising: forming a steering
device from a radar translucent material; rotatably mounting said
steering device from said forward end of said mobile platform as an
opposed pair of devices; and rotating said steering devices both
individually and in unison to generate a steering force at said
forward end of said mobile platform.
25. The method of claim 18, further comprising: compressively
loading a looped steering device at said forward end of said mobile
platform; releasing said steering device to an un-loaded position
during said powerless flight phase; and rotating at least a portion
of said steering device to generate a steering force at said
forward end of said mobile platform.
26. A reusable mach-velocity mobile platform adaptable for a
weapons release powerless glide phase of operation, comprising: a
generally tubular shaped body having an aft end, a forward end, and
a payload section disposed about a longitudinal axis of said body;
an arch wing supported at said aft end of said body; a nose
assembly connected at said forward end, said nose assembly having
an upward fixed angle-of-attack to provide lift force at said
forward end; and a plurality of landing devices extendable from
said body.
Description
FIELD OF THE INVENTION
[0001] The present invention relates in general to air vehicles and
more specifically to a reusable weapon delivery air vehicle having
an arch wing.
BACKGROUND OF THE INVENTION
[0002] Reusable launch vehicles including the space shuttle are
known. Weapon delivery systems which are self guided following
launch of the system are also known. An example of this type of
system includes the cruise missile. The cruise missile is normally
rocket launched from a stationary or mobile platform and includes
its own internal navigation equipment to enable the cruise missile,
given its originating location coordinates, to identify and fly
under its own power to a specific target. The cruise missile is
very effective at delivering relatively small explosive payloads to
a target. Disadvantages of the cruise missile include: (1) it
travels at subsonic velocities and is susceptible to being detected
and destroyed by enemy fire; (2) it includes its own engine and
fuel, reducing its payload; (3) it can strike against a single
target only; and (4) it is not a reusable platform.
[0003] It is therefore desirable to provide a reusable air vehicle
having improved survivability and a reduced detection signature,
which carries no propulsion system, but is operable at high
altitudes and travels at higher than sonic speed. It is also
desirable to provide a reusable air vehicle to reduce the operating
costs of delivering a weapons payload.
SUMMARY OF THE INVENTION
[0004] According to a preferred embodiment of the present
invention, a Mach-velocity reusable launch vehicle (RLV) is
provided which has an independently propelled launch phase, a
powerless glide phase, a weapons release phase, and a landing
phase. The RLV includes a generally tubular shaped body having an
aft end and a forward end, and a payload section. An arch wing is
supported by the body aft end. The arch wing has an upper and a
lower wing joined at distal ends by two curved end plates. A
forward steering device is provided as a pair of flight control
surfaces mounted on opposed sides of the RLV at about the
horizontal centerline. A nose assembly is connected at the RLV
forward end having an upward-directed, fixed angle-of-attack to
generate forward end lift. Radar absorptive and translucent
materials are used throughout the RLV. A rear-launch system is
preferably provided to discharge a weapons payload.
[0005] The RLV of the present invention is preferably launched as
known in the art by attachment to a rocket propelled vehicle
capable of releasing the RLV at hypersonic velocity (i.e., Mach 3
and higher) and to an altitude of 100,000 ft. or greater. The RLV
achieves maximum elevation and velocity during the launch phase,
disengages from the launch platform, reenters the atmosphere (if
necessary) at a predermined angle-of-attack, and thereafter travels
to a pre-designated location in a powerless glide phase. In a
preferred embodiment, to reduce the chance of detection and to
permit weapons release at more than one location, the RLV maintains
hypersonic velocity during the glide phase and the weapons release
phase by discharging its payload from the aft end. Following the
weapons release phase, and during the landing phase the RLV is
steered toward a landing area remote from the weapons release
location(s). Landing gear extend from the underwing for the landing
phase.
[0006] Thermal insulation attached under the body and the lower
wing under-side absorbs/dissipates heat generated during RLV
atmospheric re-entry. A high angle-of-attack is maintained and the
temperature generated by the hypersonic velocity of air moving
under the RLV is dissipated by the thermal insulation materials
which protects the vehicle's lower surfaces and shields the upper
body and the upper wing of the arch wing from the airstream's
thermal impact.
[0007] Similar features to the arch wing, the forward steering
device, and the landing gear are also described in U.S. patent
application Ser. No. 10/200,692, filed Jul. 22, 2002, which is
incorporated herein by reference.
[0008] Further areas of applicability of the present invention will
become apparent from the detailed description provided hereinafter.
It should be understood that the detailed description and specific
examples are intended for purposes of illustration only and are not
intended to limit the scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] The present, invention will become more fully understood
from the detailed description and the accompanying drawings,
wherein:
[0010] FIG. 1 is a perspective view of a preferred embodiment of a
reusable launch vehicle of the present invention;
[0011] FIG. 2 is a plan view of the reusable launch vehicle shown
in FIG. 1;
[0012] FIG. 3 is an end elevation view taken along directional line
3-3 of FIG. 2 identifying the general shape of the arch wing of the
present invention;
[0013] FIG. 4 is a side elevation view taken along directional line
4-4 of FIG. 2 showing the nose assembly angle-of-attack angle as
well as locations for the payload section and payload release
section;
[0014] FIG. 5 is a side elevation view similar to FIG. 4 showing
the reusable launch vehicle during a re-entry phase following the
vertical launch;
[0015] FIG. 6 is a perspective view of another preferred embodiment
of the present invention which includes a ring canard and a
plurality of ogive nose sections selectable for use on the reusable
launch vehicle;
[0016] FIG. 7 is a side elevation view similar to FIG. 5 showing
the alternate embodiment ring canards of FIG. 6 and their
capability to control pitch of the reusable launch vehicle;
[0017] FIG. 8 is a perspective view showing a preferred rear
release of payload from the reusable launch vehicle aft end;
[0018] FIG. 9 is a perspective view of a preferred embodiment of a
steering device of the present invention identifying a standoff
clearance permitting boundary layer flow to propagate between the
steering device and the external surface of the reusable launch
vehicle;
[0019] FIG. 10 is a section view taken at Section 10-10 of FIG. 2,
showing radar absorbing/translucent materials applied to the RLV of
the present invention;
[0020] FIG. 11 is a perspective view of yet another preferred
embodiment of the present invention having an inflatable tail cone
disposed at an aft end of the reusable launch vehicle; and
[0021] FIG. 12 is a section view taken at Section 12-12 of FIG. 3,
showing exemplary flight control surfaces on the trailing edge
portions of the lower wing.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0022] The following description of the preferred embodiment(s) is
merely exemplary in nature and is in no way intended to limit the
invention, its application, or uses.
[0023] Referring to FIG. 1, in accordance with a preferred
embodiment of the present invention, a reusable launch vehicle
(RLV) 10 includes a body 12, an arch wing 14, and a nose assembly
16. The body 12 has a generally tubular shape which supports the
arch wing 14 at an aft end of the body 12. The body 12 also
supports the nose assembly 16 at a forward end of the body 12. A
forward steering device 18 is mounted on the body 12 and is
rotatably disposed such that the steering device 18 creates side
thrust at the forward end of the body 12 when displaced from its
stowed position shown.
[0024] The arch wing 14 includes an upper wing 20, a lower wing 22,
and a pair of curved end plates 24 joining distal ends of each of
the upper wing 20 to the lower wing 22. Each of the upper wing 20,
the lower wing 22, and the curved end plates 24 include rounded
leading edges 26 and squared trailing edges 28, respectively.
[0025] The upper wing 20 has a swept wing design which will be
discussed further in reference to FIG. 2. An upper wing
point-of-contact 30 is formed between the upper wing 20 and the
body 12. From the upper wing point-of-contact 30, the upper wing
leading edges 26 each taper back to a forward facing point of the
curved end plates 24. The upper wing 20 is supported from an upper
surface of the body 12 and has a generally planar shape. The lower
wing 22 also has a swept wing design which will be discussed
further in reference to FIG. 2. The lower wing 22 has a lower wing
point-of-contact 32 at a forward leading edge of the lower wing 22
at a junction with the body 12. From the lower wing
point-of-contact 32, the lower wing leading edges 26 each taper
back to a forward facing point of the curved end plates 24. Similar
to the upper wing 20, the lower wing 22 is supported from a lower
surface of the body 12.
[0026] Referring now to FIG. 2, a body aft end 34 extends aft of
the upper wing 20 and provides a payload discharge face 36. The
payload carried by the RLV 10 exits in a payload discharge
direction A as shown.
[0027] As noted above, the upper wing 20 is connected to the body
12 at the upper wing point of contact 30. The swept wing shape of
the upper wing 20 includes a swept wing angle .theta. measured from
a body longitudinal centerline 38. The swept wing angle .theta. is
fixed for each arch wing design, and can vary between approximately
20.degree. to approximately 60.degree.. The lower wing point of
contact 32 is formed at the body 12 along the body longitudinal
centerline 38. The lower wing 22 displaces forward of the upper
wing 20 by a lower wing extension length B as shown. The advantage
of providing the lower wing extension length B will be discussed in
reference to FIG. 5. The lower wing 22 is also a swept wing having
an angle within the range of the swept wing angle .theta..
[0028] At a forward end of the body 12 the steering devices 18 are
mounted on opposed sides of the body 12. Each of the steering
devices 18 rotate at a rotation point 40 to permit a steering
device deployment angle .alpha. as shown. The steering device
deployment angle .alpha. forms an angle measured from the body
longitudinal centerline and ranges from approximately 0.degree. to
approximately 30.degree. when the steering device 18 reaches the
steering device deployed position C (shown in phantom).
[0029] Referring to FIG. 3, the design of the arch wing 14 is
provided in greater detail. The upper wing 20 has a generally
planar shape horizontally mounted from an upper surface of the body
12. The curved end plate 24 is provided to join distal ends of both
of the upper wing 20 and the lower wing 22. The curved end plate 24
serves several purposes, including: (1) the curved shape is a
structurally efficient form for joining the upper wing 20 to the
lower wing 22; (2) the curved end plate 24 prevents high pressure
air from the underside of the lower wing 22 from spilling about the
distal end of the lower wing 22 to the upper side of the lower wing
22; and (3) providing curved surfaces to join the upper wing 20 to
the lower wing 22 increases the directional stability of the air
vehicle. The lower wing 22 is provided with a horizontal portion
adjacent to the lower wing attachment point to the body 12.
Outboard of the horizontal portion of the lower wing 22, the lower
wing 22 includes a dihedral angle .phi. commonly employed for
aircraft wings. The dihedral angle .phi. ranges from approximately
0.degree. to approximately 15.degree.. In another preferred
embodiment (not shown), the upper wing 20 can also include the
dihedral angle .phi..
[0030] FIG. 3 also shows each of the steering devices 18 in their
fully deployed position. When deployed, an air flow clearance 42 is
provided between the outer surface of the body 12 and an inner
surface of each of the steering devices 18. The air flow clearance
42 provides for high velocity air flow in this standoff region
which allows boundary layer air to propagate through the entire
length of the steering devices 18, increasing its steering
effectiveness when these devices are deployed. FIG. 3 also shows a
landing gear set 44 in its deployed position. The landing gear set
44 is normally stowed during the launch and the powerless flight
phases of the operation of the RLV 10. The landing gear set 44 can
include skis, struts, or wheels. An exemplary quantity of three
components are shown for the landing gear set 44. Two of the
components are disposed in the lower wing 22 and a third component
is disposed at a lower portion of the forward end of the body 12.
Each component of the landing gear set 44 is provided with a
mechanism (not shown) to deploy and retract the landing gear set
44.
[0031] Referring to FIG. 4, both the steering device 18 and the
nose assembly 16 are shown in greater detail. The nose assembly 16
is provided as an ogive form having a forward tip displaced at an
angle .beta. above the body longitudinal centerline 38. The nose
angle .beta. is fixed when the nose assembly 16 is disposed on the
body 12. A plurality of designs for the nose assembly 16 can be
used, providing the nose angle .beta. ranging from approximately
0.degree. to approximately 12.degree. above the body longitudinal
centerline 38. The purpose for the nose angle .beta. is to provide
upward thrust by creating an angle-of-attack at the forward end of
the body 12. The additional lift provided by the nose angle .beta.
helps to compensate for the aft location of the arch wing 14 which
is provided aft of the RLV 10 center of gravity 45. The steering
device 18 includes two edges 47 formed above and below the body
longitudinal centerline 38. Each of the edges 47 are disposed at an
angle from the body longitudinal centerline 38 of approximately
10.degree. to approximately 20.degree.. A joint at the forward end
of each of the steering devices 18 is attached to the body 12 such
that the steering devices 18 rotate about a rotation axis 46.
[0032] FIG. 4 also shows in phantom a payload discharge section D
and a payload stowage section E. In a preferred embodiment, the
payload stowed in the payload stowage section E is displaceable
through the payload discharge face 36. To provide for an aft
discharge from the RLV 10, a portion of the payload stowage section
E can overlap the payload discharge section D providing clearance
for the payload to pass within and through the payload discharge
section D. Additional components (not shown) are stowed in the RLV
10 including navigation equipment, power sources, and additional
control and operational systems. These components are common to
reusable platforms or weapon delivery vehicles and are thus not
shown for clarity.
[0033] Referring to FIG. 5, the RLV 10 is shown during a re-entry
portion of the powerless flight phase. The RLV 10 is operable at
hypersonic speeds, therefore following launch, the RLV 10 is
designed to dissipate the heat of re-entry at lowered hypersonic
speeds by re-entering at a high angle-of-attack .mu. as shown. The
angle-of-attack .mu. ranges between approximately 30.degree. to
approximately 60.degree.. A thermal insulation layer 48 is disposed
on an underside of the body 12. A similar wing thermal insulation
50 is disposed on an under-surface of the lower wing 22. The
thermal insulation layer 48 and the wing thermal insulation layer
50 are preferably silicon-based materials similar to those used on
reusable platforms known in the art. The wing thermal insulation
layer 50 radiates heat outwardly when passing through a hypersonic
flow field as shown. By displacing the lower wing 22 forward of the
upper wing 20, when the RLV 10 is operated at the angle-of-attack
.mu. for re-entry, the lower wing 22 provides a shielded flow
region F wherein hypersonic flow generated temperatures are avoided
due to shielding of the upper wing 20. Thermal insulation material
is therefore not required on the upper wing 20. The high
angle-of-attack .mu. is used at reentry velocities above
approximately Mach 10. At velocities below approximately Mach 10,
the high angle-of-attack .mu. is not required. A horizontal flight
path is indicated by arrow G.
[0034] Referring to FIG. 6, another preferred embodiment of a
reusable platform 100 includes a body 102 having a ring canard 104
rotatably attached in place of the steering device 18 (shown in
FIG. 1). The ring canard 104 is disposed about a canard
axis-of-rotation 106. Each of the starboard and port sides of the
ring canard 104 can be actuated in unison or independently of each
other. By rotating the ring canard 104 about the canard
axis-of-rotation 106, the ring canard 104 deflects as shown in the
exemplary forward rotation direction H and the aft rotation
direction J. By selectively rotating the ring canard 104, forward
attitude control of the reusable platform 100 is obtained.
[0035] In a preferred embodiment, the ring canard 104 is initially
stowed during the launch phase of operation. The stowed position
(not shown) provides the ring canard 104 wrapped generally about
the perimeter of the body 102. A mechanism (not shown) releases the
ring canard and a spring tension inherent in the design displaces
the ring canard 104 into its operating position shown. Materials
for the ring canard 104 can include spring steel and composite
materials capable of producing the spring force necessary to
position and hold the ring canard 104 in its operating
position.
[0036] FIG. 6 also shows a plurality of exemplary designs for a
nose assembly. A 0.degree. ogive nose 108 is shown installed on the
body 102. A positive 5.degree. ogive nose 110 and a positive
10.degree. ogive nose 112 are also shown. Accordingly, a plurality
of individual nose assemblies can be installed on the body 102 to
affect the lift force generated by the nose assembly.
[0037] Referring to FIG. 7, an elevation view showing the reusable
platform 100 of FIG. 6 is provided. The ring canard 104 is shown in
each of 3 potential operating positions when rotated about the
canard axis of rotation 106 (shown in FIG. 6). In a forward rotated
position a download is applied to the reusable platform 100 via the
ring canard 104. In a neutral or centrally vertical position, the
ring canard 104 will produce additional upload as shown if the
reusable platform 100 is operating at or above an operating
angle-of-attack .delta. as shown. If the reusable platform 100 is
operating at a horizontal flight path indicated by horizontal
flight path direction arrow G, a central or perpendicular position
of the ring canard 104 will generate no load on the reusable
platform 100. In the horizontal flight path G, an aft positioned
ring canard 104 will produce an upload for the reusable platform
100. The advantage of the ring canard 104 is the capability of
producing either an upload or a download depending upon the rotated
position. The upload or download force is applied at the forward
end of the reusable platform 100 and acts to rotate the reusable
platform 100 about the platform center of gravity 114. This
provides pitch control for the reusable platform 100. By rotating
individual sides of the ring canard 104 in the forward rotation
angle H and the aft rotation angle J (shown in FIG. 6), side force
can be generated to turn the reusable platform 100 starboard or
port.
[0038] As best seen in FIG. 8, in a preferred embodiment, the RLV
10 of the present invention discharges payload (e.g.,
sub-munitions) in a rear-release direction. During the weapons
release phase, a payload 52 is released from the aft end of the RLV
10 in the payload discharge direction A. A plurality of known means
can be used to discharge the payload 52. Exemplary means for
discharge include using a drag parachute (not shown) to pull the
payload 52 from its stowed position, or an ejection device (not
shown) to propel the payload 52 in an aft direction, triggered
either by an onboard signal or a remote signal received by the RLV
10. In the exemplary application of sub-munitions shown in FIG. 8,
a sub-munition guidance system 54 as known in the art is employed
for self propulsion of the payload 52 to a target or ground site.
The RLV 10 can carry a plurality of payloads, and can deliver
sub-payloads to multiple locations.
[0039] Referring to FIG. 9, the steering device 18 shown in FIG. 1
is provided in greater detail. The steering device 18, when
deployed in its steering device deployed position C (shown in FIG.
2), produces a lateral force which directs the forward end of the
RLV 10 in the desired direction. At a steering device deployment
angle .alpha., boundary layer air flow propagates through the air
flow clearance 42 to maximize the effectiveness of the steering
device 18. The steering device 18 rotates about a rotation axis 46
to achieve any steering device deployment angle .alpha. between
approximately 0.degree. to approximately 30.degree.. Material for
the steering device is preferably selected from the group of low
dielectric materials able to reduce radar reflection.
[0040] Referring to FIG. 10, a cross section taken through the arch
wing 14 and the body 12 shows exemplary material layers and an
exemplary grouping of submunitions. The wing thermal insulation
layer 50 is preferably a silica-based material to reflect reentry
induced heating at the lower wing 22. The lower wing 22 can be
constructed of metal, including titanium or aluminum, or a
composite material, and preferably includes a radar absorbing
material (RAM) layer 68 preferably coated on both surfaces of the
lower wing 22, but at least those surfaces of the lower wing 22 not
covered by the thermal insulation layer 50. The lower wing 22 is
bonded (e.g., by adhesive) or mechanically joined (e.g., by rivets)
to the curved end plates 24 at lower wing joints 70 and 72,
respectively. The curved plates 24 are in turn bonded or
mechanically joined to the upper wing 20 at upper wing joints 74
and 76, respectively. Because no metal structural members are
required in their cross sections, the material for the curved
plates 24 and the upper wing 20 is preferably a radar translucent
material such as a low dielectric material.
[0041] FIG. 10 also shows that a RAM layer 78 is applied to the
outer surface of the body 12. An exemplary payload cylinder 80 is
shown in its installed position, having a plurality of sub-munition
chambers 82. A stowage cylinder 84 is also shown, for stowing an
inflatable tail cone and extendable shaft (items 404 and 406,
respectively, shown and discussed in reference to FIG. 11).
[0042] As best seen in FIG. 11, another preferred embodiment
includes a reusable platform 400 having a body 402. An arch wing is
not shown in the details of FIG. 10 for clarity. Following the
powerless glide phase, the reusable platform 400 begins the landing
phase of operation. During the landing phase it is important for
the reusable platform 400 to obtain a maximum free glide distance
to maximize the RLV operating range. To minimize aerodynamic drag,
and following the release of the payload, the reusable platform 400
further includes an inflatable tail cone 404. The inflatable tail
cone 404 extends via an extendable shaft 406 from an aft end 408 of
the reusable platform 400. Following extension, the inflatable tail
cone 404 self-inflates to form a general cone shape providing
clearance to the aft end 408. The inflatable tail cone 404 includes
a rounded leading face 410 and a tapering body 412. Following the
landing phase the inflatable tail cone 404 and the extendable shaft
406 are reloaded through the aft end 408 to a stowed position 414
(shown in phantom).
[0043] Referring now to FIG. 12, the plurality of components
installed on the lower wing 22 are shown. A starboard elevon 56, a
port elevon 58, a starboard aileron 60, and a port aileron 62 are
installed adjacent to an aft edge 64 of an upper surface 66 of the
lower wing 22. The starboard elevon 56 and the port elevon 58 are
installed inboard of the starboard aileron 60 and the port aileron
62. The positions of the elevons and the ailerons can be modified
from those shown in FIG. 12 depending upon the geometry of the
lower wing 22 and the flight characteristics of the RLV 10. As
previously noted, the curved end plates 24 prevent higher pressure
air under the lower wing 22 from bypassing the flight surfaces of
the lower wing 22 by escaping to the upper surface 66 of the lower
wing 22. Air flow is therefore maintained over the upper surface 66
in the general direction of flow direction arrows K.
[0044] The RLV of the present invention offers several advantages.
The arch wing design increases the available lift by approximately
50% over a single planar wing. The end plates joining both the
upper wing and the lower wing of the arch wing provide directional
stability to the air vehicle and maintains air flow over the flight
control surfaces of the lower wing in a flow direction generally
perpendicular with the surface of the lower wing. The nose assembly
design provides additional lift through the use of a fixed
angle-of-attack. The forward steering devices are located forward
of the center of gravity of the reusable platform therefore
generating side thrust and enabling additional pitch control for
the RLV. The slender and rounded surfaces of the reusable platform
including the swept arch wing reduce the radar cross section.
[0045] The capability of achieving hypersonic speeds by boost from
a separate launch platform or detachable booster rockets enables
the RLV to reach targets at higher than sonic velocities, reducing
the likelihood of enemy detection and destruction of the RLV. In
the preferred embodiment, by releasing the payload in an aft
direction, payload doors which generate aerodynamic drag and radar
reflective cavities are not required, therefore the RLV is able to
maintain higher than sonic velocities during the powerless flight
and weapons release phases. Radar absorbing or radar translucent
materials are provided at exterior surfaces of the body, the
forward steering device, and for wing portions of the arch wing. A
reusable platform of the present invention can be used at both
atmospheric and low earth orbital elevation, increasing the range
of operation. The arch wing of the present invention in concert
with the forward steering devices provide sufficient vertical
stabilization such that a rudder, winglets, or other vertical
stabilizers known in the art are not required for control of the
RLV.
[0046] The materials selected for use for the RLV can vary
depending upon the application and temperature range of operation.
Composite materials can be used for the arch wing provided that the
thermal insulation protects the lower temperature capability areas
of the arch wing. Higher strength materials including titanium and
steels can also be used for the body, the arch wing, the forward
steering devices, and the nose assembly of the reusable platform.
An RLV of the present invention is capable of velocities up to
approximately Mach 30 when provided with thermal insulation
materials on selected under-surfaces to protect the under-surfaces
during an RLV re-entry phase. The powerless gliding phase is
initiated at above Mach speed velocities providing increased range
of operation with reduced chance of detection.
[0047] The description of the invention is merely exemplary in
nature and, thus, variations that do not depart from the gist of
the invention are intended to be within the scope of the invention.
Such variations are not to be regarded as a departure from the
spirit and scope of the invention. For example, a rocket engine is
described as the means for achieving launch for the reusable
platform of the present invention, however, the RLV can also be
launched by other means. The launch phase is performed by a
separate craft known in the art carrying the RLV to a desired
elevation and/or by booster rockets temporarily attached to the
body of the RLV as known in the art.
* * * * *