Looking for the smartest
The presence on board a combat vehicle of a large number of various types of ammunition, on the one hand, allows it to hit various types of targets, and on the other, it seriously increases the mass of ammunition carried. It is worth considering the loss of time to reload the weapon with the appropriate projectile. In addition, the consumption of "stupid" projectiles on the target is often outweighed in the final cost by single and effective shots of "smart" ammunition. This is especially true of modern asymmetric threats, when many miniature Davids are able to turn any Goliath into scrap metal. Drones with mini-bombs, mobile mortar crews, high-speed boats armed with both rocket weapons and simply equipped with a couple of hundred kilograms of explosives with a fanatic on board - all these irritants make us look for technological answers in all developed countries of the world. Demand, as you know, gives rise to supply, and now we are witnessing a process of gradual increase in the "intellectual" capabilities of artillery weapons - primarily in the niche of small and medium calibers.
The fact that it is time to get rid of the classic fragmentation ammunition was first discussed in the 60s of the last century, when the opportunity arose for a detailed study of the physics of the explosion of a projectile. It turned out that fragmentation grenades, when exploded, form a too low density of fragments, some of which, moreover, go into the air and ground. Even proximity fuses, if they change the situation, it is not drastically: some of the fragments still fly past the target. The formation of the fragmentation field was actually accidental, while the negative effect was introduced by longitudinal cracks on the shell of the projectile, which formed in the first moments of the explosion. They formed long and heavy fragments, called "sabers", which accounted for up to 80% of the total mass of the hull. They tried to find a way out in the search for the optimal composition of steel, but this path turned out to be in many ways a dead end. The cost of production was increased by the shells of the shells with the given crushing parameters, which, moreover, seriously reduced the strength. Not the most advanced percussion fuses, which showed themselves not from the very best side, were also brought up in the water-filled rice fields of Vietnam, the deserts of the Middle East and the swampy soils of the lower Mesopotamia. Therefore, the engineers decided to revive the shrapnel munitions, which were successfully buried even before the Second World War. In the 60s, new targets for artillery appeared - calculations of anti-tank weapons, soldiers protected by individual armor, as well as the birth of the first small-sized air targets such as anti-ship cruise missiles. New alloys based on tungsten and uranium came to the aid of shrapnel ammunition, significantly increasing the penetrating effect of ready-made submunitions. So, the Americans, experienced in improving the effectiveness of their weapons, in Vietnam for the first time used ammunition with arrow-shaped striking elements, each of which weighed from 0.7 to 1.5 grams. Each projectile contained up to 10,000 waxed arrows, which accelerated to 200 m / s when the expelling charge was detonated. It was dangerous to accelerate the arrows to a higher speed: the chances of destruction of the elements from a powerful explosion were great.
Gradually, the evolution of a new type of shrapnel led to the emergence of small-caliber ammunition for 20-mm cannons. This was the German DM111 projectile for the Rh202 and Rh200 guns weighing 118 grams. and containing 120 balls, each of which pierced a duralumin sheet 2 mm thick. In Russia, a 30-mm projectile was intended for similar work, in which there were 28 bullets of 3.5 grams each. each one. This ammunition was developed for aircraft guns GSh-30, -301, -30K; its distinguishing feature was the fixed interval of the actuation of the expelling powder charge (at a distance of 800 to 1700 m), from which the shrapnel bullets flew at an angle of 8 degrees.
Probably one of the most advanced shrapnel ammunition was the Swiss AHEAD from Oerlikon - Contraves AG in 35 mm caliber, which possesses certain rudiments of simple artillery "intelligence". At the bottom of the projectile is an electronic remote fuse, which is triggered at a strictly defined time. For this, artillery installations capable of firing such ammunition must have a rangefinder, a ballistic computer and a muzzle channel for entering a temporary installation. The input channel or induction programmer consists of three solenoid rings, the first two of which measure the projectile departure speed, and the third transmits the detonation time parameters to the remote fuse. With a muzzle velocity of the projectile of about 1050 m / s, the entire process of measuring the muzzle velocity, calculating and programming the projectile takes less than 0.002 seconds.
The AHEAD (Advanced Hit Efficiency And Destruction) anti-aircraft projectile, exploding with 152 ready-made tungsten cylinders, allows you to fight aircraft, UAVs and missiles at a distance of up to 4 km. Typical examples of gun systems using Swiss shells are MANTIS, Skyshield and Millennium, equipped with a 35 mm Oerlikon 35/1000 automatic cannon. In particular, the cannons are capable of firing in three modes: classic single and single with a rate of 200 rounds per minute, as well as bursts of 1000 rounds per minute. AHEAD was developed back in the 90s, went through many upgrades and actually became the founder of a whole new class of KETF projectiles (Kinetic Energy Timed Fuze, kinetic energy ammunition with a timed fuse, often referred to as AHEAD / KETF or ABM / KETF).
Caliber is shallow
If the 35mm AHEAD seems too large, then Rheinmetall offers the "smart" 30mm PMC308 ammunition, which is already in use in NATO countries. Such shells can seriously save the amount of ammunition. The developers claim that up to 50% in comparison with 35 mm and up to 75% in the case of 40 mm. The shells fit the Rheinmetall MK30-2 / ABM1 and Wotan, named after Wotan, the supreme ancient German deity. It will not be a problem to use the projectile with guns that have a programmer not on the muzzle, but in the ammunition feed mechanism. For example, Orbital ATK's 30mm Mk44 Bushmaster II cannon. The PMC308 is a projectile packed with 162 submunitions, each weighing 1.24 grams. In the event of a miss, the "smart" ammunition self-destructs after 8, 2 seconds of flight, having time to overcome 4 km during this time.
Perhaps the most high-tech device in the described technique is a miniature bottom fuse, unified for both 35-mm and 30-mm AHEAD / KETF. It consists of a receiving coil of a non-contact programmer, an electronic temporary device with an energy source, an electric igniter, a safety-actuating mechanism with a detonator and an expelling charge containing 0.5 g of explosives. In this case, the generator of the power source is started when an overload from a shot is fired - this saves energy consumption in standby mode in the ammunition rack. The electronics have an interesting fuse that does not allow programming to detonate less than 64 ms after exiting the barrel. This creates a "safety zone" from being hit by its own shrapnel around the cannon with a radius of about 70 meters. And, of course, the absence of a contact fuse allows the automatic cannon to work at a target through bushes and dense thickets of vegetation. And, most importantly, the 30mm and 35mm AHEAD / KETF rounds are dual-mode. The first is a mode with a programmed detonation range, and the second is without programming at all. That is, an expensive projectile can penetrate 24-40 mm brick walls only due to kinetic energy. In this case, the ammunition is destroyed, scattering the deadly contents already behind the obstacle.
By the way, programmers on the muzzle and in the ammunition supply mechanism are not the only options for "communication" between the gun and the projectiles. Rheinmetall has developed a 40-mm high-explosive fragmentation round DM131 HE IM ESD-T ABM for the German Heckler & Koch GMG grenade launchers and the American General Dynamics Mk 47 Striker. A special feature is the Vingmate 4500 (Vingmate Advansed) fire control system, the principle of operation of which is similar to the correction of the flight of an anti-tank missile. Only here, with the help of coded infrared signals, the time of the explosion in the air is transmitted to the grenade, which has already managed to overcome 4 m from the muzzle in flight.
At the same time, the grenade, which accepted its command for execution through eight on-board IR receivers, can no longer be reprogrammed in order to avoid receiving someone else's command. Here, as in the case of AHEAD, with a burst from a Heckler & Koch GMG grenade launcher, you can arrange a spectacular "pearl thread", that is, simultaneously detonate several grenades on the flight path at once. To implement such a complex mechanism of operation on a grenade launcher, a laser rangefinder and an infrared projector of a programmer with a control unit must be installed.
50mm EAPS ammunition
To deal with attacking artillery shells, mines and cans of explosives, "smart" shells of 20, 30 and 35 mm caliber are often not enough. The 50-mm Enhanced Bushmaster III cannon was created specifically for solving such problems, which can also be executed in a 35-mm version.
The weapon was originally developed as part of the EAPS Extended Area Protection and Survivability program, the leadership of which is entrusted to the US Army Research, Development and Design Center. Of course, the caliber of 50 mm implies the presence of armor-piercing shells, but the main thing is the AirBurst (AB) SuperShot 50 mm PABM-T ammunition, equipped with a remote detonation system in the air. At first it was believed that the new gun would fit the modernized version of Bradley, but there was not enough space in the BMP for such a weapon with ammunition, so it was decided to use the promising NGCV (Next Generation Combat Vehicle) vehicle as a platform.
By the way, the cannon on the Griffin III Demonstrator prototype lifts up into the sky almost vertically (up to 85 degrees), clearly showing which targets may be in priority.
To successfully control the fire of such a powerful gun against air targets such as asymmetric threats, an interferometric radar station is now in the development of EAPS, capable of tracking 6 targets at once and controlling the movement of ten 50-mm ammunition towards them. The target is fired by a twin Enhanced Bushmaster III installation on a wheeled chassis.
Interestingly, initially, in 2007, the Americans from the developer Texton Systems hoped that the most optimal form of the projectile would be a classic ogival with a six-bladed tail. But tests showed that such a scheme does not differ in flight stability, and the cylindrical tip of the ammunition was equipped with a needle. In addition, in the area of the center of mass of the projectile, a monopulse correction engine was placed, containing 5, 9 cm3 fuel and creates, if necessary, an impulse perpendicular to the axis of the projectile. That is, this "smart" projectile is able not only to explode at the right time by radio commands from the ground, but also to adjust its flight to the target. And this, let me remind you, is in the form factor of a 50-mm automatic cannon projectile.
The next innovation of the EAPS cannon can be considered a cumulative fragmentation warhead MEFP (Multiple Explosive Formed Penetrator), which, when detonated, forms a directed field of 7-12 miniature tungsten motantalum "shock nuclei". This turned out to be a necessary measure in the fight against thick-walled mines, against which ordinary tungsten shrapnel is ineffective. In addition, explosives form a circular field of fragments of a previously fragmented shell of the projectile - this is already for more vulnerable drones.
