Note: Descriptions are shown in the official language in which they were submitted.
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The present application is a divisional of Applica-
tion Serial NoO 364196 filed November 7, 1980.
Technical Field
This invention relates to a munitions system and
su~munition which may be used in ground-to-ground or
air-to-ground tactical warfare situations against armored
vehicle targets. The subject submunition includes a
missile containing a projectile.
sackground Art
Conventional munitions designed to counter armored
vehicles include both ground and air-launched projectiles
which must impact the target to be effective. Accuracy
of the initial launch conditions of elevation, azimuth
and velocity, coupled with subsequent aerodynamics effects
during the trajectory to the target, dominate the per-
formance of these munitions. Guided munitions do not
rely so heavily on the accuracy of initial launch con-
ditions but are generally more complex and costly and
potentially vulnexably to enemy countermeasures.
An object of the present invention is to provide a
submunition which is both effective and relatively
inexpensive as compared to guided systems yet which
offers the opportunity to search for and engage a target
during its flight.
Disclosure of the Invention
In accordance with the invention, a submunition
overflies a target area following a ballistic path
in a manner similar to that o~ a clay pigeon or
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"Skeet" at a shooting range. The munition carries a down-
ward directed projectile such as a Mizure-Chardin type war-
head commonly known as a self-forging fragment warhead.
Preferably the submunition is configured as a short cylinder,
the length to diameter ratio being governed by a number of
system considerations. Means such as spin imparted to the
submunition provides stability during flight with the pro-
jectile directed downward. An infrared sensor or other
target sensing device is embodied on the submunition to
trigger the firing of the warhead when an appropriate signal
is received. To increase the ground area scanned by the
sensing element, a wobbling or precession motion is impart-
ed to the submunition during its fliqht if such motion is
warranted by the engagement scenario.
Launch of the submunition along its trajectory
may be accomplished by explosive or rocXet propelled ejec-
tion from a suitable launch tube or by centrifugal forces
imparted by spinning of a munition delivery vehicle about
an axis parallel to but offset from the munition spin axis.
In the latter case, the munition receives both spinning and
lateral displacement motion. Other methods of imparting spin
are by a strap, a pin/groove arrangement, a friction band or
rack and pinion. Wobbling motion may be imparted by an off-
center bob-weight or a small explosive coning charge.
In accordance with the present invention there
is provided a missile for a submunition adapted to be
launched along a trajectory to overfly a target comprising:
a missile having a vertical spin axis; means for launching
the missile, along a trajectory; means for imparting a spin-
ning motion to the missile about said axis; and means for
imparting a lateral precessional motion to the missile
relative to the trajectory.
Brief Description of the Drawin~s
The foregoing and other objects, features and
advantages of the invention will be apparent from
the following more particular description of pre-
--3--ferred embodiments of the invent~on, as illustrated
in the accompanying drawings in which like reference
characters refer to the same parts throughout the
different views. The drawings are not necessarily to
scale, emphasis instead being placed upon illustrating
the principles of the invention,
Fig. 1 is a cross-sectional view of a submunitions
device embodying this invention;
FigO 2 i5 an exploded view of the submunitions
device of Fig. l;
Fig. 3 shows the submunition missile of Figs. 1
and 2 as it is launched from a launching tube;
Fig. 4 is a plan view of the missile positioned
in the launching tube of Fig. 3 and showing the strap
for imparting spin to the missile with firing;
Fig. 5 shows a trace of the ground area subject
to attack by a wobbling, spinning missile;
Fig~ 6 is a plan view similar to Fig. 4 but
showing an alternative embodiment for i.mparting spin
to the missile by an off-center weight;
Fig. 7 is a plan view of another embodiment of
imparting spin ~o th~ missile by a pin and groove;
Fig. 8 is a plan view of yet another embodiment
for imparting spin including a rack and pinion;
Fig. 9 is still another means of imparting spin
including a friction surface;
Fig. 10 is a perspective view of an alternative
embodiment of th~ munitions device with means for
imparting wobble to the spinning missile.
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Best Mode of Carrying Out the Invention
As shown in Fig. 1 and the exploded view of Fig.
2, a missile 12 is in the form of a canlster having
a cylindrical warhead housing 14. The housing 14 is
separated into an explosive charge chamber 18 and an
electronics chamber 20 by a recessed floor 16. Electronics
in the chamber 20 are covered by a flat, end plate 22.
The opposite end of the canister missile 12 is closed
by a lens 24. The metal lens 24 retains an explosive
charge 25 in ~he chamber 18 and serves as a projectile
when the exploslve charge is ignlted.
Similar lens projectiles are used in conventional
mines and the like but are directed upward. The lens
is termed self-forging because, when fired, the explosive
charge inverts the curvature of the lens so that the
lens becomes a bullet shaped projectile. With the
present arrangement, the lens 24 is directed downward
to provide a concave lower end to the submunition.
With the cylindrical housing 14 and flat end plate 22
the lens provides an inverted saucer configuratlon. The
spinning inverted saucer has high stability in flight
and is a source of additional lift to the missile. The
stability of the spinning missile insures that the
projectile, lens 24, is directed downward along the
entire missile trajectory.
To sense a target, an infrared target detection
device with optics 26 is mounted to the outside of
the housing 14. The target detection device might
also be mounted within the housing. Within the
electronics chamber 20, two batteries 28 and 30 serve
as the power supply. Target detection elec-
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tronics 31 and 32 analy~e the signals received fromthe infrared detector and distinguish between a
target, such as an armored vehicle, and background,
other suitable target detectors may, for example, be
of the magnetic, optical or audio type.
A sa~ing and arming device 34 is provided to
prevent ignltion of the explosive charge 25 until the
safing and arming device detects the translational
and angular acceleration of the mis~ile when it i8
fired. To initiate firing of the explosive charge
25, a precision initiater coupler 38 is provided,
This initiater coupler is a small charger which is
ignited upon detection of a suitable target.
In use, the missile is propelled from a launch-
ing device such ~s shown in Figs. 3 and 4 at a
velocity of 100 to 200 feet psr second to ranges
of several hundred feet. The launcher is a rectangular
t~be 40 from which the missile 12 is fired by an
sxplosive charge 4~ To impart spin to the missile
12 about a vertical axis, a frangible strap 44 is
fixed at one end to th~ firing tube and wrapped
partially around the missile 12. The opposite end
of the strap is fixed to the missile bv r~vets. This
strap has notches 46 formed adjacent ths rivets so that,
as the missile leaves the tube 40, the strap breaks
to disconnect the missile from the tube.
It can be noted in Fig. 3 that the strap is
attached to the missile above the center of gravity.
This imparts a torque in a roll plane as the strap
is released. As a result, the missile spins o~f
with precession, that is with a wobbling motion.
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With wobbling of the missile, the submunition scans
the ground and can fire upon a larger area, This
larger area is indicated by the coning action shown
at 48 in Fig. 3 and by the target area wlth flight
shown in Fig. 5. As the distance of the misslle above
ground increases and then decreases along its tra-
jectory, the ground which is scanned by the infrared
detector and to which the pro~ectils 24 is directed
is as shown at 50 in Fig. 5. Without wobble, the
ground scanned is along a single straight l~ne 52.
It can thus be seen that the target area, or footprint,
of the missile is much greater with spin and wobble~
With such a large target area determined by the entire
missile trajectory and the extent of the wobble, thQ
missile need not be fired directly to, or even directly
over, a target. This greatly reduces the accuracy
required for single shot firing of a cannon or mortar,
and it reduces the number of devicss which mus~ be
fired with random firing. Because fewer devices must
be fired, each device can be provided with increased
munitions capacity. Also, the projectile 24 is fired
directly or almost directly downward onto the targetO
The top of a target is o~ten its most vulnerable side.
To insure that any target within the footprint
of the missile be detected, the maximum interscan
spacing 54 in the firing path 50 must be less than
the expected target width. To that end, the spin
rate must be sufficient for a given velocity of the
missile.
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othex ~eans for imparting spin to the missile
are shown in Figs. 6-9. In Fig. 6, a weight 56
increases the inertia on that side of the missile.
That side thus has a slower acceleration, and spin
is imparted.
In Fig. 7, a pin 58 on the missile is guided
by a groove 60 in the launching tube 40. When the
misslle is fired, the pin foll~ws the groove and
thus imparts spin. The groove may be open at its
terminal end or the pin may be frangible. Alterna-
t~vely, the groove may be in the misslle and the
pin may be secured to the launching tube 40,
In Fig. ~, complementary teeth on the missile
and in the launching tube 40 providP a rack and
pin~on effect. And in Fig, 8 a high friction sur-
face 66 to one side of the launching tube 40 pro-
vides a s~milar effect.
Rather than by placing the spin imparting mean
off center, ~obble can be separately induced. For
example, a small coning charge may be firea after
the missile has been launched. The charge would be
positioned on the missile to provide torque in a
roll plane. Fig. 10 shows another means for impart-
ing wobble to the spinning missile, A bob 68 is
positioned at the end of a hinged support arm 70 such
as a rod or a flexible line. After the missile is
launched centrifugal force from the spin of the mis-
sile causes the bob to swing outwardly. Since the arm
is connected off center, the missile wobblesO The
frequency of the wobble can be changed by adjusting
the length of the arm 70.
In each of the embodiments described, the
miss~le 12 is fired over a target, When the target
is sensed, the explosive charge 25 carried by the
missile is isnited an* a projectile 24 is propelled
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downward onto the target. As alrsady noted, in many
cases the top of a target is more vulnerable than
the f~ont or sides. Thus, a projectile fired from
above has greater effect. Also, the trajectory of
the missile ls not significant so long as the tar-
get is in the target area of Fig. 5.
It should be recognized that the projectile
24 may be of any type. For example, it may be
solid or fragmentary, and it may carry lts own
exploslve charge.
Tha mi~sile need not be launched by mean of
an explosive charge. For example, a centrifugal
release of the missile is feasib~e. Also, the
launcher nsed not be located on the ground. It
may, for example, be dropped by parachute with a
plurality of missiles launched as the launcher
falls toward the ground.
While the invention has been particularly
shown and described with reference to preferred
embodiments thereof, it will be understood by those
skilled in the art that various changes in form and
details may be made therein wi~hout departing from
the spirit and scope of the invention as defined by
the appended claims.
