At the very beginning of 1961, the successful tests of the first American solid-propellant missile, the Minuteman-1A, brought the United States to a leading position in the development of medium-range ballistic missiles. The leadership of the Soviet Union at that time could not put up with the fact that the USSR was becoming the second after the United States in this race. Already on April 4, 1961, the government of the USSR, by its decree, sets before Soviet engineers the task of developing and creating at least three types of solid-propellant medium-range missiles. After that, several design bureaus began work on the creation of the first Soviet solid-propellant missiles.
In total, there were several projects under the general leadership of Sergei Korolev. Rocket 8K96, its second stage, was created in KB-7 of the Leningrad Artillery Plant "Arsenal", led by the chief designer of the KB Pyotr Tyurin. The 8K97 rocket was developed at the Perm Design Bureau under the leadership of Mikhail Tsirulnikov, and it was also planned to develop the first stage for the 8K96 rocket there. The 8K98 missiles, or its other designation, the RT-2 and 8K98P intercontinental missile, were created by S. Korolev himself together with Igor Sadovsky, one of the creators of the RT-1 rocket. Another Soviet designer Mikhail Yangel took over the development of the 8K99 rocket; according to the project, this rocket was supposed to have the first stage on solid fuel, the second on liquid fuel. After a thorough study of the working drawings, it was decided to use the development of M. Tsirulnikov as the first stage, which has the best performance and the PAL-17/7 mixed solid fuel engine.
However, in 1963, all work on the 8K96 or RT-15 project, which is essentially a RT-2 rocket, without the first stage, was suspended until the RT-2 rocket was completed. After that, the RT-15 was again resumed in 1965 as part of the 15P696 mobile complex, it was adopted by the Strategic Missile Forces of the Soviet Army and launched into serial production at the Leningrad Plant No. 7. The development of the SPU (self-propelled launcher) 15U59 based on the T-10 tank was carried out at the design bureau of the Kirov plant under the leadership of Zh. Ya. Kotin. Also, developments were carried out to create launching complexes on a wheel drive and on railway platforms. For the first time, the missile system under the designation SPU "object 815" was demonstrated during the parade on November 7, 1965.
After the first test launches, it became clear that the range of the RT-15 rocket (according to NATO classification SS X-14 "Spacegoat") exceeds the calculated one and reaches 4.5 thousand kilometers. Given this fact, P. Tyurin is instructed to continue work on the further development of the rocket. The work was carried out until 1970, during which time 20 test launches of RT-15 missiles were carried out at the Kapustin Yar range. After that, the work was completely curtailed, and the designer P. Tyurin began to create the first solid fuel rocket in the USSR for nuclear submarines. The 8K96 design consisted of two stages (the second and third stages from the RT-2 rocket) with solid-propellant engines installed on them, specially modified to ensure optimal operation, both at launch and in flight. In the tail section of the rocket, four stabilizers were placed on the first stage. The rocket was controlled in flight using propulsion engines (15D27-first stage and 15D92-second stage) and split nozzles. The warhead of the rocket, the total mass of the charge is 535 kg, was nuclear, monoblock type with a capacity of 1, 1 Megatons.
The missile was aimed at the target using an inertial control system with a gyroscopic platform, created at the Scientific Research Institute of the AP under the leadership of the chief designer N. Pilyugin. The launch was controlled by a remote launch control system developed at the Impulse Design Bureau under the leadership of T. Sokolov. The fuel charges, according to some sources, were fastened to the rocket engine, according to the technology of the NII-9 g of Biysk, by pouring the fuel mass into the engine housing. According to other sources, the fuel charges were supplementary, manufactured according to the technology of the Research Institute-130 g of Perm. It can also be assumed that both options were probably used, as in the RT-2 rocket. At the first stage, NII-9 fuel charges were used, at the second stage, NII-130. However, according to the recollections of the test participants, who claim that after opening the nozzle plugs, at least a bucket of water was poured out of the engine, which is not typical for the engines of the RT-2 rocket stages. The total length of the rocket was 12, 7 meters, diameter from 1, 9 to 2, 1 meters, launch weight 1.87 tons, warhead useful weight more than 500 kg.
