A means for increasing the drag of a munition to effect a course correction having coplanar interlocking pairs of drag plates (24, 26) being laterally extendable from an undeployed configuration, substantially contained within the munition, to a deployed configuration. The drag plates (101, 103) are provided with projections (34, 38) and slots (36, 40), the projections (34, 38) of one of a pair of drag plates being adapted to locate in the slots (34, 40) of the other drag plate in the undeployed configuration and being adapted such that they extend beyond halfway into the munition. A deployment means (60, 62, 70, 72) retains the drag plates in the undeployed configuration until receipt of a control signal and then effects deployment of the drag plates, the distance travelled between the deployed and undeployed configurations being determined by the extent of the projections (34, 38).

Means for increasing the drag on a munition

A tail fin assembly for a guided projectile which is capable of withstanding the high pressures experienced during launch, which is also capable of stabilizing the projectile during initial flight shortly after emergence from the cannon or large gun barrel and which is also capable of freely spinning relative to the projectile front section for the remainder of the flight to minimize projectile roll to accomplish all of these capabilities sequentially during a single launch. The assembly includes the projectile and a rotatable member, preferably a tail fin assembly with tail fins which is rotatable about the projectile major axis and which is normally locked against rotation about the projectile. A locking structure is provided for locking the rotatable member against the rotation which is responsive to a predetermined condition to permit rotation of the rotatable member about the projectile. The tail fins are normally retracted and secured to the rotatable member and are extendable in response to a predetermined condition.

Unlocking tail fin assembly for guided projectiles

A training projectile that utilizes flutes or flats to augment roll damping characteristics and thereby cause the projectile to crossover into a gyroscopically unstable trajectory pattern at a predetermined time. Prior to the crossover, the training projectile maintains a gyroscopically stable trajectory, which enables extrapolation to ascertain the trajectory of a non-training projectile that does not have an augmented roll damping section. The unstable trajectory pattern substantially reduces the distance the training projectile can traverse, thereby reducing the amount of area required for a training range.

Range limited projectile using augmented roll damping

The present invention uses aerodynamic heating caused by air-friction during flight of a training projectile. The training projectile includes a nose, a body and a tail section. The body has a forwardmost end secured to the nose, and a rearwardmost end secured to the tail. Air friction during flight causes deployment of “passive” shape memory alloy (SMA) aerodynamic members in an assembly to induce drag of the training projectile thereby limiting an effective range of the projectile.

Training projectile using shape memory alloy members

A hold down device (100) positioned on the projectile to exert a known spring force in opposition to the centrifugal force provides an inexpensive, light weight and reliable delayed fin deployment mechanism for boosted fin-stabilized spinning projectiles. When the forcing moment produced by the centrifugal force acting on the fin (102) exceeds the opposing moment produced by the hold down device, the hold down device will release the fin allowing it to swing into its deployed position. Thus, proper selection of the spring force and positioning of the hold down device will cause the fins to deploy at a predetermined spin rate. The delayed deployment of multiple fins is attained by providing a plurality of like hold down devices or by providing a single hold down device that releases a lanyard (106) when deployed.

Delayed tail fin deployment mechanism and method

A spin-stabilized training missile is equipped with a stabilizer device for reducing spinning in order to decrease the flight range. The training missile is designed so that its stabilization attainable solely by the spin upon firing is not sufficient for a stable flight in the practice range. The required additional stabilizing in the practice range is obtained by a stabilizer device or control airfoil effecting simultaneously, after leaving the practice range, such a spin reduction that the training missile becomes unstable and the range of flight is controlled.

Spin-stabilized training missile

Drallstabilisierter Ubungsflugkorper mit einer Einrichtung zur Reduzierung des Dralls zwecks Verringerung der Flugweite. Swirl-stabilized practice flight body with a device for reducing the swirl in order to reduce the flight distance. Der Ubungsflugkorper ist derart ausgelegt, das seine durch den Drall beim Abschus allein erreichbare Stabilisierung fur den stabilen Flug im Ubungsbereich nicht ausreicht. The practice flight body is so designed that its only achievable by the spin on firing stabilization for the stable flight in the practice range is not sufficient. Die erforderliche zusatzliche Stabilisierung im Ubungsbereich wird durch ein Leitwerk erreicht, das gleichzeitig nach Verlassen des Ubungsbereiches eine solche Reduzierung des Dralls bewirkt, das der Ubungsflugkorper instabil wird. The required additional stabilization in the practice range is achieved by a tail unit, which causes at the same time after leaving the range exercise such a reduction of the spin that the practice flight body becomes unstable.

Walter Diesinger

Papers

Spin-stabilized training missile

Spin-stabilised training projectile