U.S. patent number 3,898,932 [Application Number 05/310,626] was granted by the patent office on 1975-08-12 for non-hazardous ring airfoil projectile for delivery of non-lethal material.
Invention is credited to Abraham Flatau, Miles C. Miller, Donald N. Olson.
United States Patent |
3,898,932 |
Flatau , et al. |
August 12, 1975 |
Non-hazardous ring airfoil projectile for delivery of non-lethal
material
Abstract
A rotatable airfoil projectile comprising a hollow closed
circular ring wing surrounding a central open area with a
non-lethal riot control agent positioned within the hollow ring.
The projectile consists of an aerodynamic lifting body of a thick
ring wing geometry which uses spin imparted to it from a launching
means for its gyroscopic stability The combination of aerodynamic
stability characteristics and high spin rate (i.e. above 2,000 rpm)
results in a flat trajectory and extended range capability. The
projectile ruptures on impact due to centrifugal and impact forces
to distribute the non-lethal riot control payload about the target
area. The sub-sonic launch velocity avoids bodily harm due to
impact with a person even at point-blank range.
Inventors: |
Flatau; Abraham (Joppa, MD),
Olson; Donald N. (Lutherville, MD), Miller; Miles C.
(Joppa, MD) |
Family
ID: |
23203387 |
Appl.
No.: |
05/310,626 |
Filed: |
November 29, 1972 |
Current U.S.
Class: |
102/502; 244/3.1;
102/503; 244/34A |
Current CPC
Class: |
F42B
12/50 (20130101) |
Current International
Class: |
F42B
12/50 (20060101); F42B 12/02 (20060101); F42b
013/46 (); F42b 011/32 () |
Field of
Search: |
;102/38,92.1,92.2,92.3,92.4,92.6,92.7,56,41,64,67,90,42C,65,66,65.2
;244/3.1 |
References Cited
[Referenced By]
U.S. Patent Documents
|
|
|
3170405 |
February 1965 |
Jungermann et al. |
3289585 |
December 1966 |
Rudolph et al. |
3710720 |
January 1973 |
Mawhinney |
|
Foreign Patent Documents
Primary Examiner: Stahl; Robert F.
Attorney, Agent or Firm: Edelberg; Nathan Gibson; Robert P.
Church; Robert W.
Government Interests
DEDICATORY CLAUSE
The invention described herein may be manufactured, used or
licensed by or for the government for governmental purposes without
payment to us of any royalty thereon.
Claims
What is claimed:
1. In a projectile having an annular ring shape with a substantial
tear drop airfoil cross-section defining a hollow interior and
being defined by major annular inner and outer substantially
curvilinear surfaces defining the diametric extent of said shape
and being terminated by leading and trailing edges which define the
longitudinal extent of said shape, the improvement comprising a
non-lethal incapacitating payload disposed within the hollow
interior of said projectile and being confined by an outer
resilient structure forming said shape further including rupturable
means which ruptures upon impact with the target for disseminating
said payload.
2. The projectile of claim 1 wherein said rupturable means defines
at least a part of one of said surfaces.
3. The projectile of claim 1 wherein said rupturable means is in
the form of a band.
4. The projectile of claim 3 wherein said band will not rupture
during launch at velocities up to 300 ft/sec and a spin velocity of
at least 2,000 RPM's.
5. The invention of claim 1 wherein said rupturable means is a
composite band which has at least one weakened portion.
6. The invention of claim 5 wherein said weakened portion comprises
perforations through said band.
7. The invention of claim 1 wherein the said rupturable means is
preloaded to near rupture when spinning at over 2,000 RPM's when
traveling in its flight trajectory.
8. The projectile of claim 1 wherein said rupturable means is
composed of a band of non-elastic material disposed over the
payload portion of said projectile.
9. The projectile of claim 8 wherein said band is preloaded to near
its structural failure point due to centrifugal force created by
the spin of the projectile so that the band will fail and
disseminate said payload upon impact with a target.
Description
Briefly stated, the present invention relates to a non-lethal ring
air foil projectile adapted for use in pacifying or dispersing
unruly persons such as, for example, mobs.
The wide spread mob violence of recent years has spurred the
development of numerous mob control devices including notably rifle
fired or tear gas grenades and other types of projectiles and also
various hand-held weapons for use by military and civil police to
control mob violence. Desirably the authorities should be equipped
with projectile means to disperse or control mobs without killing,
disfiguring or permanently injuring any members thereof.
Unfortunately, the mob control devices of a projectile nature
proposed heretofore suffer from certain serious disadvantages. If
fired from too close, e.g. point blank, the projectile can cause
serious injury to a target individual. On the other hand, the usual
mob control projectile, as for example a tear gas grenade, is not
very accurate when fired from a distance great enough for the
policeman to be out of range of injurious objects such as rocks
which might be hurled by rioters.
It has now been discovered that the ring air foil munition
disclosed in copending application of A. Flatau, Ser. No. 272,252,
filed July 17, 1972, which in turn is a C.I.P. of Ser. No. 105,751,
filed January 1971, now abandoned, is well adapted to mob control,
particularly if modified into the structure of the present
invention.
The munition projectile comprises a ring air foil or ring wing,
i.e. a body of revolution generated by an air foil cross-section
rotated 360.degree. about an axis beneath and parallel to the
longitudinal direction of the air foil cross-section. The hollow
region internally of the ring wing houses the payload and explosive
train. In particular, the munition projectile of the aforementioned
copending application comprises an aerodynamic lifting body of a
thick ring wing geometry which utilizes a spin in excess of about
2,000 rpm imparted thereto by the launching means for gyroscopic
stability. Normally this projectile has a near neutral static
stability and associated aerodynamic performance characteristics
which provide predictable repeatable trajectories and extended
range. These aerodynamic characteristics are based on the
generation of a lift force, as gravity tends to pull the projectile
downward, and the low drag shaping. To provide for payload
capacity, the wing cross-section should exceed 25% of the chordal
dimensions.
Important to use of a ring air foil projectile for mob control
purposes is its relatively low launching velocity, being always
launched at a subsonic velocity e.g. below about 300 ft/sec. Low
launch velocity and an extended range are desired attributes for a
mob control device which will not cause lethal injury on impact of
the human body at point blank range, yet be capable of launch from
a distance far enough to be out of the rock throwing range of
rioters e.g. 50 to 100 meters.
The principal object of the present invention is to provide a
projectile, containing a riot control payload, which will not cause
lethal injury upon impact with the human body due to kinetic energy
even at the point blank range.
Another object of the present invention is to provide a projectile
containing a mob control payload, capable of being launched
accurately from a distance.
A further object of this invention is to provide a frangible ring
air foil which produces a high degree of payload dissemination at a
target area.
Still other objects of the invention and the advantages of the
invention will become apparent from the detailed description
thereof hereinafter set forth.
Briefly stated, the ring air foil projectile of the present
invention is a relatively thick ring wing. A non-lethal payload is
to be carried inside the ring air foil and the materials and
structure of the ring air foil are such that the ring air foil is
frangible, rupturing on impact. The ring air foil wing material is
stressed by the forces involved with its launch spin to very near
the rupture point; the additional forces applied by impact then
cause rupture releasing the payload.
For a more detailed description of this invention and disclosure of
the preferred embodiments thereof, reference is now made to the
attached drawing wherein:
FIG. 1 is a diagrammatic view showing the rupture of the ring air
foil projectile;
FIG. 2 is a diagrammatic view showing a weapon adapter attached to
the muzzle of a rifle;
FIG. 3 is an exploded view showing a weapon adapter to eject the
projectile from the weapon, a sabot and the projectile;
FIG. 4 is a view of a preferred mode of projectile showing the
projectile body with the inner wall extended;
FIG. 5 is a fragmentary view of the projectile;
FIG. 6 is a cut-away view of the projectile mode of FIG. 4 showing
a break band, slits in the outer wall and internal
configuration;
FIG. 7 is a view of the preferred mode of FIG. 6 showing the
completed projectile and the projectile in the direction of flight
and the sense of rotation in flight; and
FIG. 8 is a view showing the projectile mounted in the sabot for
ejection from a weapon.
As is shown in FIG. 1, the frangible ring air foil 1 is adapted to
fragment upon impact, releasing its payload 2 into the impact area.
The ring air foil 1 (FIGS. 4-7) is a ring with an inner wall 3 and
an outer wall 4 joined at leading edge 5 and trailing edge 6 with
space between walls for payload 2. Walls 3 and 4 are, of course,
contoured to be airfoil shapes and together have a thickness to
chord ratio ratio in excess of 20%.
Since a principal object of the present invention is to provide a
non-lethal launched (rather than thrown or hurled) projectile; the
material used for the ring air foil should be particularly light
weight, even soft, such as plastics, rubber, etc. Brittle light
weight plastics are known to the art and, therefore, the actual
materials from which projectile 1 is fabricated form no part of the
present invention. In addition, thin wall sections or pre-weakened
wall portions, particularly in outer wall 4, may be employed to
facilitate rupture upon impact. Such expedients are too well known
for detailed discussion thereon. Illustrated by the drawing is a
preferred construction of the ring air foil projectile intended to
insure rupture on impact, yet permit relatively rough handling
without rupture prior to launch. Since the ring air foil projectile
is a low velocity device with a sub-sonic launch velocity usually
not exceeding about 300 ft/sec, frangibility can be assured by
relating high spin to wall strength. Centrifugal force due to spin
loads the wing wall very close to its rupture point. Thereafter,
even a soft impact will increase wall stresses beyond the rupture
point.
It may be noted that mechanical launch means such as a rifle and
adapter 7 (FIG. 2) are capable of imparting spin in excess of 2,000
rpm, normally 4,000-6,000 rpm. Spin stressing the wing wall offers
several safety features. The ring wing material can be made strong
enough for safe handling, even mishandling without rupture. Also in
the event any ring air foil projectile does land without rupture
and payload release and then is hurled back by a rioter, it will
not normally rupture or fragment upon impact (for lack of
prestressing through spin). Although a rifle launch means has been
illustrated, the projectile could be fired from a pistol adapter or
a special hand-held weapon designed for this non-lethal use
only.
The importance of non-lethality makes the preferred size range for
the non-lethal air foil of the present invention surprisingly
narrow i.e. 2-3 inch diameter. The minimum size projectile should
be too large to impact principally in someone's eye, yet the
largest projectile should be small enough so that its impact energy
will not crush the face.
A desirable attribute of the non-lethal ring air foil projectile of
the present invention is that accuracy and a relatively extended
range are combined with the relatively low launch velocity of below
about 300 ft/sec, preferably 250-300 ft/sec. The ring air foil
projectile launched from a rifle mounted adapter 7 (See FIG. 2) is
accurate to about 100 meters (or yards). As compared to tear gas
grenades, the ring air foil has the advantage of a relatively flat
trajectory.
In the preferred embodiment illustrated in the drawing, the
frangible ring air foil 1 is an envelope type container fabricated
of a soft and resilient material such as soft rubber or plastic.
Inner wall 3 is formed (e.g. molded) integral with outer wall 4
joined by shoulder 9. Inner wall 3 nests within outer wall 4, with
the edge 10 of inner wall 3, being heat sealable in conventional
manner to the edge 11 of outer wall 4 after a payload 2 is loaded
between inner wall 3 and outer wall 4 to form trailing edge 6.
Thus, the diametric extents of our ring air foil final shape are
defined by the exposed surfaces of walls 3 and 4 and band 14 which
overlays wall 4. Leading edge 5 and trailing edge 6 define the
longitudinal extent of our projectile. The ring air foil projectile
structure illustrated is a modified Clark-Y air foil. The ring wing
is thick, made so by blending two air foils having different
thickness to chord ratios in back-to-back relationship. Their
respective thickness to chord ratios is nominally 22% and 11% and
the resultant ring air foil having a thickness to chord ratio of
28.5%. However, other back-to-back air foil cross-sections are
contemplated as being within the scope of this invention so long as
such other ring wings have a nominal thickness to chord
cross-section ratio of at least 20%.
The payload 2 which may be any material adequate to meet the
requirements of the intended non-lethal given applications such as
powder, liquid, encapsulated gels or liquids, and pelletized
lacrimatory materials can be loaded between walls 3 and 4 by
conventional filling and dispensing apparatus in conventional
manner prior to sealing off trailing edge 6.
According to the structure of the preferred mode of the invention
illustrated in the drawing, recess 12 is formed in outer wall 4 (by
conventional molding techinique) and slits 13 are formed in outer
wall 4 in a non-continuous saw-tooth slit line configuration (by
conventional die cutting techniques). A resilient break band 14, of
a flexible material which has a low elongation under load, has
perforations 15 formed therein (by conventional perforation means).
Band 14 is mounted adhesively within recess 12 with each line of
perforation 15 set so one end thereof coincides with the
intersection of two lines of slits 13 at border of recess 12; the
opposite end of the line of perforations 15 then becomes located
one-half way between a pair of intersecting lines of slits 13 at
the opposite border of recess 12 (as may be seen in FIG. 7). The
band 14, which is added before introducing payload 2, prevents the
opening of slits 13 during introduction of the payload 2 within the
projectile 1, during storage, shipping and handling of the loaded
projectile, and even during its flight prior to impact with the
target.
Perforations 15 control the strength of break band 14 so that
centrifugal force loads due to spin in flight (in excess of 2,000
rpm) preload break band 14 to near structural failure, so that
break band 14 will be deformed and open on impact with the target,
as shown in FIG. 1, disseminating the payload at a target area.
When the ring air foil projectile is launched from an adapter 7
attached to a weapon 8, e.g. a rifle, propulsion forces cause the
sabot 16 to separate from adapter 7, releasing ring air foil 1 into
its relatively flat trajectory. Sabot 16 is fabricated from a
light-weight (foam) material with a plurality of fingers 17 formed
therein. Fingers 17 are torn away from base 18 of sabot 16 at
undercut 19 in flight by centrifugal force to permit projectile 1
to separate in flight from sabot 16. Adapter 7 will normally be
designed to impart the desired spin rate to projectile 1. Sabot 16
breaks into a plurality of pieces, slows rapidly and drops to the
ground almost immediately.
Desirably, the projectile wall is thickened and shaped to form a
shoulder 9 at the point of intersection of inner wall 3 and outer
wall 4 with enough weight of material to act as ballast for center
of gravity control for the ring air foil. In flight, projectile 1
flies in an attitude with rounded edge portion 5 leading, feathered
edge portion 6 trailing, and the projectile rotating in a clockwise
direction, as shown in FIG. 7. The smooth low drag airfoil shaping
minimizes velocity decay and spin decay of the projectile in flight
conserving the launch imparted kinetic energy and centrifugal
forces. Thus, impact at short or nominal ranges e.g. 30-100 meters
creates a large and rapid increase in the circumferential loading
of band 14 at one or more of the rows of perforations 15 in the
break band, in sufficient excess of the load already imposed on it
by centrifugal forces to break the band 14 completely at one or
more of these rows of perforations. Immediately, the full
centrifugal force of the payload bears against the outer wall 4 of
the projectile 1 so that the dashed slits 13 structurally fail,
deform, and open up, releasing the payload 2 as shown in FIG. 1.
The high tangential velocity of the individual payload particles
(due to the high spin rate of the projectile) disperses the payload
into a cloud in the target area upon release from the ruptured
projectile.
The low drag, flat trajectory due to lift, and accuracy of the ring
air foil projectile enables it to be aimed and fired at a point
target from a distance so that only that amount of payload needed
to expose a point target to the effects of the payload agent need
to be delivered thereto. This eliminates the necessity to
contaminate a large area in order to assure that a point target is
exposed to the payload agent. For example, the ring air foil
projectile can be fired into a window from about 100 meters or to
hit a specific individual at 30-50 meters.
* * * * *