15Zh53 Russian intermediate range ballistic missile. Development of a modernised version of the 15Zh45 IRBM began at the beginning of the 1980's. Flight trials either began in 1985 or were cancelled prior to their planned start in 1986. In 1988 the project was cancelled following the signature of the INF Treaty that banned intermediate range ballistic missiles. The missile (known to the Pentagon as both the SS-20 Mod 3 and the SS-28) would have had a range of 7500 km with a single warhead, or 5500 km with multiple warheads.
Compared to the Pioner-U it used a larger launch container, a larger MIRV bus with greater accuracy. The KB Minsk Auto Factory developed a lighter, more comfortable crew cabin - important on constant field deployments. More...