US Government As Represented by the Secretary of the Army

Bruce P Burns

Richard D Kirkendall

William F Donovan

Robert P Kaste

William H Drysdale

Stephen A Wilkerson

Louise D Kokinakis

James F Newill

Christopher P Hoppel

Travis A Bogetti

Peter Plostins

The invention reduces the amount of force and acceleration transmitted to the vehicle occupant in a vehicle subject to the shock of a land mine explosion. In the invention, a set of crushable composite tubes are placed between the vehicle floor and the seat of the vehicle. As the floor moves due to the blast loading, the crushable tubes deform, absorbing the energy of the blast and reducing the acceleration transmitted to the seated occupant.

Apparatus for absorbing mine blast energy

To determine the optimum load a laminate member or element is capable of bearing, a three-dimensional progressive analysis is proposed in which the stress and strain states of each ply of the laminate are subjected to failure criteria. If there is failure, new ply stiffness parameters are calculated. Thereafter, the ply is tested with the new parameter until the optimal load is determined. If no failure is detected for a given stress and strain for the ply then the load may be incremented and again applied to the ply, for further testing. Alternatively, the same load may be applied to the ply for a further period of time, until the optimal load is determined and/or the analysis is deemed to be finished.

Method for assessing the effects of loading forces on a composite

A double ramped, saboted, kinetic energy assembly automatically aligns a jectile in a gun tube. The assembly has an acceleration activated device consisting of a split centering ring causing alignment during the early phase of the shot motion of the projectile. The assembly also includes a series of small protrusions or a continuous expandable ring which forces and maintains the projectile into a straight aligned position during its traversal of the gun tube. The assembly may have either a smooth bore or a rifled bore gun tube. The disclosure also include a method related to the assembly.

Stabilization band/ring assembly for aligning a projectile in a gun tube

An improved segmented doubled ramp sabot for launching a sub-caliber projile, comprising a plurality of longitudinal ribs disposed on the forward and aft ramp sections of the sabot, and a plurality of longitudinal ribs disposed between an obturating band seat and a conical borerider. The combined cross sectional area of the double ramp segments, together with the combined cross sectional area of the ribs, are such that the sum of these areas is approximately equal to the cross sectional area of a double ramp sabot representative of prior art. As a result, axial stiffness is unaffected, and uniform shear traction forces between the sabot and projectile are maintained. In addition, the transverse bending stiffness of the sabot is improved, thereby reducing in-bore vibration and shot dispersion while allowing maximum energy transfer to the projectile. Use of a stiffer material for the ribs further improves transverse bending stiffness and performance.

Splined sabot

A propellant igniter that is controlled by temperature and is activated by cceleration. The igniter includes a booster or primer for igniting a propellant charge. A spring-loaded firing pin is cocked by a rotating sear that, when released, energizes the booster. Rotation of the sear is controlled by a plurality of springs one of which produces a moment on the sear that is a function of temperature while others, a plurality of captive springs, produce restoring forces that are inversely proportional to acceleration as detected by an acceleration sensor. When the captive springs are sufficiently relaxed by the acceleration sensor, due to an increased acceleration, to allow the sear to rotate, the cocked firing pin is released, the booster is activated and ignition occurs.

Temperature-compensated, acceleration-activated igniter

A saboted projectile having an elongated sub-projectile having a double-r sabot mounted thereon. The sabot includes a main body portion having a radially extending forward scoop and a central bulkhead between which a toroidal-shaped cavity is formed. A self-sealing container extending between the scoop and the bulkhead encloses the cavity in which a solid propellant is contained. A through-hole, formed in the bulkhead, extends from the cavity to the rear surface of the bulkhead. The through-hole has an opening at the rear of the bulkhead for housing a blow-out plug. An igniter is mounted in the plug for igniting the solid propellant contained in the cavity after a predetermined delay. Ignition may also be achieved via pores or openings in the container which may contain a deterred propellant.

Solid propellant-carrying caboted projectile

An ammunition round for an artillery gun comprises, as an armor piercing nd, an outer tubular disposable sabot and an inner projectile which are joined by interlocking means to join them until exiting from the gun muzzle and separates them in ballistic flight. The interlocking means comprises left-handed threads and right-handed threads; both directions of threads being on both the inner wall of the sabot and the outer wall of the projectile. In one embodiment the two directions of threads are on axially tandem sections and in another embodiment they are on the same section, to form a herringbone pattern with raised diamond-shaped protrusions.

Armor piercing ammunition having interlocking means

A wedge-shaped seal for sealing against leakage of gun gases past a projele in the bore of a gun barrel includes a wedge-shaped tip having rearward angled forward and rear surfaces which is preloaded to bear the tip against the projectile body. A wedge-shaped region between the lip and the projectile body is partly collapsed by the pressure of gun gases on the rear surface of the lip to improve the seal. A similar seal may be provided with the bore of the gun barrel.

Projectile seal

Longitudinal stresses in the explosive grain of a rapidly accelerated high xplosive projectile are absorbed in longitudinal reinforcement members and are transferred therefrom to the casing of the projectile. Transmission of the acceleration load from the grain to the longitudinal reinforcement members may be by friction, adhesive bonding or by area mismatch. A stress decoupling layer in the aft end of the projectile may be employed for matrix stress decoupling.

Longitudinal reinforcement of high explosive fill in projectiles

A segmented sabot utilizes a double ramp configuration and a centrally poioned obturating band in alignment with the center of gravity of an in-bore projectile to improve the uniformity of the shear traction forces at the interface between the sabot segments and a subcaliber projectile, to reduce propellant gas blow-by and to enhance projectile in-bore and trajectory stability. The increased uniformity of shear traction forces between sabot and projectile interfaces and propellant gas self-sealing design permits a reduction in sabot weight of sufficient magnitude to increase the velocity of the projectile at the muzzle exit.

Double ramp discarding sabot

The invention deals with the manufacture of fully segmented sabots used in he launching of subcaliber projectiles. The prior method required the machining of individual sabot segments and fitting them on to the sub-projectile. The improvement involves the casting of the sabot segments with the shimmed sub-projectile pre-positioned in a mold.

Growing community of inventors

Churchville, MD, United States of America

Bruce P Burns