R-36-O / SL-X-? FOBS
In the early 1960s, the Soviets needed a way to overcome the forward base advantage held by the west. The west had forward bases in Turkey, Europe, and Asia from which shorter range missiles and bombers could attack the USSR. Following the failure of placing missiles to Cuba, the Soviets turned to technology to overcome the lack of forward positioning. The Vostok launches had previously demonstrated that the Soviets possessed the technology necessary to orbit a space vehicle and then land it in a specific target. In this, there was an implicit assumption that nuclear weapons could be placed in orbit and returned to Earth at any time and place. Khrushchev made this suggestion in 1961, but in March 1962, as part of the rhetoric preceding the Cuban crisis, he made yet another, more ominous suggestion.
"We can launch missiles not only over the North Pole, but in the opposite direction, too. Global rockets can fly from the oceans or other directions where warning facilities cannot be installed. Given global missiles, the warning system in general has lost its importance. Global missiles cannot be spotted in time to prepare any measures against them."
This statement was the first hint of a new concept called the fractional orbit bombardment system (FOBS) that had been under development since 1961.
The orbital missile 8K69 was initially deployed on 19 November 1968, and the first regiment with the R-36 orbital missiles was put on alert on 25 August 1969. The missile was phased out in January 1983 in compliance with the SALT-2 treaty, which prohibited the deployment of FOBS systems.
The R-36O SS-9 variant 3 SCARP with a modified upper stage was equipped with an orbital nose cone, which contained an instrumentation section, a single-chambered liquid propellant retrorocket motor and a nuclear warhead. Western estimates were that the orbital missile carried a one- to three-megaton warhead. Once placed into low-Earth orbit, the ICBM possessed unlimited range and the ability to approach the US from any direction, avoiding US northern-looking detection radars. This type of approach would give little or no warning that a warhead was inbound. The reentry vehicle came down in less than one revolution, hence the "fractional" orbit.
Following the failure of their first two tests in 1966, the Soviets conducted nine launches between 25 January and 28 October 1967 following the same distinct flight profile. The missiles would be launched in the late afternoon into an elliptical, near-polar low-Earth orbit and de-orbiting over the Soviet landmass before one complete orbit. This profile allowed the Soviets to monitor the deorbit, reentry, and impact. US planners viewed FOBS as a pathfinder system intended to precede a conventional ICBM attack and take out key retaliatory forces. The FOBS would circumvent the existing US ballistic missile early warning radars and hit SAC airfields and missile silos before the bombers could take off or missiles launched. FOBS could have also conceivably destroyed ABM radars, disrupt US retaliatory capability, destroy command posts, the White House, and the command and control network. But, due to its limited accuracy and payload, FOBS was deemed ineffective against hardened targets.
The 1967 Outer Space Treaty basically allowed the Soviets to orbit everything but a nuclear warhead. The FOBS system allowed them the ability to deploy the weapons system minus the warheads without violating the treaty.
By 1968 the Soviets' FOBS program conducted two flights per year to indicate operational status. Although the Soviets deployed FOBS in 18 silos, political events in the U.S. prevented any serious examination of the system. At that time it was unclear to US intelligence whether the Soviets were developing FOBS, or ballistic missiles with depressed trajectories and deboost capabilities.
Join the GlobalSecurity.org mailing list