Friday 13 May 2016

World of Tanks History Section: New Life for Rockets

Using a rocket against a tank is very tempting. Rockets can carry a powerful warhead and can be launched without an expensive barrel: all you need is a rail. In the 1930s, Soviet pilots were already using rockets to fire at enemy planes.

During the Great Patriotic War, an attempt was made to use rockets to destroy German tanks, but it turns out that this wasn't so simple.

Failed Trials of 1941

A report on the first day of trials held at the Sofrino proving grounds on August 6th, 1941, can be summarized in one sentence: "Since the trials were performed at night, the rockets were not found." The trials were done to determine the precision of the rockets, and it's very clear that the results did not impress the testers.

The next day was more productive, since it was possible to find the rockets. It turned out that firing and hitting are two different things. The horizontal dispersion of the rockets launched from a kilometer away reached 50 meters. It was clear that hitting a tank at this distance was not possible, but the trials had to establish the effect of a rocket on an armoured plate anyway.

The plate was placed at 200 meters, and five rockets were launched, none of which hit. Testers once again wrote about the large dispersion and moved the target to 100 metres. Here, they got lucky: one of two rockets hit the plate and left a small dent. This was enough for GAU, but its workers were specialists. Others were specialists in the field of imagination. Today, these kinds of people write books about people going back in time and changing the course of history. Since no one though of that genre yet, all they could do was flood the State Committee of Defense with letters, or even send them directly to Stalin.

Mikhail Mil's Rocket Gun

In October of 1942, engineer Mikhail Leontyevich Mil was working as an assistant for Chief Engineer Nikolai Ilyich Kamov at factory #290. The reader may recall that these two reached glory as the creators of domestic helicopters, but that was several years later. In 1942, Mil presented a proposal for an anti-tank gun that fired 82 mm RS-82 rockets.

The designer promised that one soldier was enough to operate the gun. A special device was used to ensure that he would not be harmed by the exhaust, diverting it to the side.

The mass of the launcher was 14 to 20 kilograms, depending on whether it was installed on a tripod or a heavier mount. The effective range was the same as for a regular anti-tank rifle: 100-200 meters. Mil was certain that his specially designed anti-tank rocket could penetrate even heavy armour. Another advantage of the project was that production could be quickly set up in the Urals.

Interestingly enough, Mil's project was not pure theory. In his letter, he wrote that "Since this proposal was made (August 15th, 1942) the author, with the assistance of comrade S.V. Paskhin, made and tested 3 launchers. Trials showed the need for improvements, which are being done now."

Workers of the sorting department at the Commissariat of Defense were experienced judges of proposals. This one didn't seem like lunacy, so it was forwarded to the GAU. There, specialist studied Mil's proposal in more detail and responded that "the odds of hitting a 3 meters wide and 2 meter tall target are 3.4%, which means that out of 100 rockets launched, no more than 4 will hit. Due to this fact, development of comrade Mil's proposal is not productive."

Rocket Guns and a Self Guided Mine

There were three projects for rocket guns: Mil, Mil-Paskhin, and Kamov-Korotkih. While the negative response made its way to the Urals, all three types were assembled and tested. It's not hard to predict that the trials confirmed the suspicions of the artillery specialists. The rockets missed constantly.

Despite GAU's rejection of factory #290's proposals, the engineers kept working on them on their own initiative. N.I. Kamov informed Moscow of this in 1944. He noted that the weapon is reliable and harmless to the shooter. Kamov also presented his ideas about why the rockets don't fly straight and how to improve on that.

"Since many military leaders consider having this weapon for infantry very useful, I thought about this issue and came to the following conclusions:
  1. The poor precision of the weapon is caused by random chance in the formation of the rocket jet.
  2. Rotating the RS-82 rocket should neutralize that factor."
Kamov was ready to keep working on his guns, but no response from GAU was found in the archives. If there was one, it was likely that GAU informed Kamov that rotating the rocket would weaken the effect of the HEAT jet. By 1944, developers of domestic rocket launchers came to this conclusion themselves.

No story about rocket anti-tank weapons would be complete without the mention of another curious design. In late November of 1942, the SPTM self-guiding anti-tank mine designed by military engineer 2nd grade Rasskazov was tested at the GABTU proving grounds. The solution was simple and creative: a rocket propelled explosive charge was attached to a wire, hung across the road. A tank that hit the wire freed a pin, which would launch the rocket and hit the side of the tank.

Trials showed that the pin doesn't work very reliably. Out of 11 launches, it failed 4 times. In other cases, the rocket shot straight into a T-34's side. The penetrative power of the rocket was tested on PzIII and Pz38(t) tanks. While imperfect, its HEAT warhead reliably penetrated 30 mm of German armour.

The rocket was sent back to correct discovered defects. Whether there were some difficulties with that or some other factors came into play is unknown. While the SPTM did not make it into the Red Army, it can be considered a precursor to modern HEAT mines.

Original article available here.


  1. Any idea if there was any influence from the 2.36 inch "Whip" bazooka launchers sent to the USSR via Lend-Lease in 1942? I'm always surprised there is no mention of the bazooka in Russian accounts.

    1. I haven't encountered bazookas in documents yet. In all these early RPG experiments that I read about, the projectile is a repurposed RS-82 rocket. Internal documents aren't shy about admitting inspiration or straight up requesting that a foreign solution be copied ("Ferdinand style" muzzle brake on early IS-2s, many references to the design of the PzIII during T-50 design, the "English" MK-4 observation device, etc), so presumably if I ever come across a reverse engineered bazooka, it will be honestly labelled as such.

  2. I'm surprised the 1941 trials didn't avoid the accuracy problem by having the rockets slide along a wire which had one end bolted to the target armor plate.

    They might have had to launch the rocket from a higher location, to compensate for the catenary path of the wire and keep the rocket from hitting the ground, but this is hardly insurmountable. (Putting tension on the wire to keep it straight would be a bad idea because, when the rocket detonated, there could be a few hundred meters of wire whipping back towards the observers.)

  3. I'm extremely curious how the Red Army viewed/used American bazookas they got from lend-lease and why they didn't capitalize on them more. IIRC, they viewed them as inefficient.

    1. The requirements for anti-tank rockets included being able to hit a tank at 1000 meters, which is quite unrealistic with WWII era tech.