Fractional Orbiting Bombardment Systems (FOBS)
The Soviets explored the use of Fractional and Multiple Orbit Bombardment Systems (FOBS and MOBS), which would have made nuclear strikes "from any direction" possible. Such strikes would greatly complicate any enemy strategic defensive measures.
In the fall of 1967 the United States Secretary of Defense informed the public of Soviet fractional orbiting bombardment systems (FOBS). The very few Americans who had read the 1967 edition of Soviet Rocket Troops were not surprised.* According to this book, Soviet military leaders had already advised their public: ". . . into the armaments of the troops constantly come new kinds of weapons and combat equipment, among which are orbiting rockets, small caliber solid-fueled intercontinental rockets on self-propelled launchers, and also fully automatic complexes of strategic rockets, characterized by exceptionally high reliability and combat readiness." (p. 5, 1967 ed.) Colonel Astashenkov is the editor of the Soviet aerospace magazine Aviation and Cosmonautics. General Colonel Tolubko is First Deputy Commander in Chief, Strategic Rocket Troops.
Subsequent comment on FOBS by McNamara's successors indicated that there was still uncertainty concerning the purposes of this delivery system. Secretary Clifford, in his January 1969 posture statement, noted that the Soviets might be trying to develop the system for delivery of weapons against soft targets either via orbit or by depressed trajectory. Secretary Laird, in his statement on March 19, 1969. before the Senate Armed Services Committee, mentioned the possibility of FOBS' use against bomber bases, and also cautioned against assuming that FOBS carried no nuclear weapons.
US military leaders believed that the Soviets were using the SS-9, their most powerful ICBM, to boost FOBS into orbit, and that a 10,000-pound payload could be carried by the orbiting vehicle.
When Khrushchev bragged in early 1960 about possessing a secret weapon, he may have referred to an orbital bomb, but most Western press accounts tended to discount this possibility. The Soviet leader was probably threatening with a weapon system then only under consideration or perhaps in its initial development stage. The capability was certainly within reach of either the Americans or Russians. We apparently feel this system would not add substantially to our offensive capability, for evidently the US did not developed such a weapon and do not intend to.
The US consideration of “cost effectiveness” did not faze the Soviet programmers. Most likely they felt just the opposite, for Secretary of Defense Robert S. McNamara stated on 3 November 1967 that the Russians were possibly developing such a system. His announcement was based on the evaluation of several Soviet Cosmos vehicles that had been launched during the year. Once again the USSR was developing a weapon that would insure, along with the rest of the Soviet defense establishment, a varied defense posture. The FOBS, when viewed in the overall picture, should surprise no one in the West. The Russians were not rushing helter-skelter into development of all these varied weapons and force structures. Like their space exploits, these developments reflect a carefully considered program, capable of employment and obviously styled to suit their needs, preferences, and plans.
The Soviet-built fractional orbit bombardment system (FOBS) allowed missiles or warheads to remain in earth orbit before beginning their descent. FOBS gave the USSR the ability to launch a mass attack against the U.S. from any direction rather than just depending on a ballistic pathway arching over the North Pole. FOBS was also potentially convertible into MOBS -- a similar satellite weapons carrier designed for delivering its payload against earth targets after multiple orbits.
Any possible Soviet knowledge of the US program to develop an over-the-horizon radar did not dampen the Russian idea that the FOBS would be an effective system worth having in their inventory. Even though this delivery vehicle is regarded as less capable than the ICBM for carrying heavy warheads, the Soviets’ capabilities and intentions had been misjudged before.
For a time the Soviets were developing a powerful thrust system through clustering of rocket engines, that enabled FOBS delivery of very high-megaton (MT), heavier warheads-warheads larger than anything in the West. It would offer them delivery capability via the Southern Hemisphere, thereby outflanking our three BMEWS stations and other radars. The idea of delivering FOBS via this route probably resulted from Soviet scheming in the late ‘50s and early ‘60s looking toward a “super” ICBM to deliver warheads on the US undetected. Two arguments against development of such a tactic — inaccuracy and small on-target MT capability — were probably valid and considered by Soviet decision-makers. Their method of circumventing these disadvantages apparently was the FOBS.
During the Moscow parade of 1965, the Soviet Union displayed a 115-foot missile, the SCRAG, which they claimed was capable of striking the United States on the first or any successive orbit. This was not the first time the Russians claimed a space weapon capab:Llity. The Soviet Union in the past has made many claims that it possessed "orbital rockets". Initially few people gave credence to these. Soviet claims, but with the SCRAG, the Russian interest in space weapons was Clearly evident. Moreover, the technological capability to develop and deploy a space weapon system is clearly within the Russians' grasp.
A space weapon system can be deployed in various modes. It might be used as a Fractional Orbit Bombardment System (FOBS), in which the vehicle is placed into orbit, butbefore it completes one revolution of the earth, a warhead is reentered on a pretargeted facility. A more complex mode is the Multiple Orbit Bombardment System (MOBS). A MOBS would be placed in orbit for varied periods of time; then eventually the warhead would be reentered on a pretargeted or even retargeted facility.
There are many variations to the MOBS concept. Some look at low orbiting vehicles which would reenter after a short period of time·- a few revolutions or a few days. Other concepts envision vehiCles itt long duration orbits or eccentric orbits in which warheads are for all practical purposes stored in space. Then, when necessary or desired, these vehicles would be placed into low orbits for final reentry of the payload on a target.
Although not truly a space weapon, one other system is often considered in a discussion of space weapons: the Depressed Trajectory ICBM (DICBM). The DICBM does not achieve orpit. It is a ballistic missile placed on a trajectory that has a low a:pogee resulting in a depressing of the entire trajectory. This depressed trajectory results in shortened radar detection ranges, shorter flight times, and some trajectories which can exploit holes in existing detection systems.
The primary area of contention appeared to be deployment. The tests the Russians conducted clearly had application to FOBS or DICBM, and the two systems were closely related. Both offer a new dimension to Soviet strategic capability (with inherent advantages and disadvantages), and both may provide a technological data base which could eventually lead to development of advanced orbital weapon systems. Present US space and missile defense capabilities were inadequate to cope with either system.
The tests of FOBS/DICBM began in December 1965 with a suborbital launch from Tyura Tam. The vehicle was placed on a depressed trajectory (120 NM apogee) with slightly over 11 minutes of coast before third stage ignition. The vehicle exploded after third stage ignition. Two more suborbital tests were run in February and May of 1966. The February test may have been successful, and the May test apparently · was a success. After the three suborbital tests, the Russians began orbital tests. The first test was in September 1966, but they did not appear to achieve success until their third try in January 1967. This vehicle (Cosmos 139) was launched from Tyura Tam to the south with a 49.7 degree inclination.
This brought the vehicle back for reentry in the Kapustin Yar recovery area. The vehicle was in a very low orbit with an apogee of 112 miles and a perigee of 72 miles and was reentered before it completed one revol:ution - meetng the expected criteria of a FOBS. Since that test they launched 12 more tests of the system, all on a similar profile. Each of the vehicles was carried under the Cosmos label, and during the period from 17 May 1967 to 18 October 1967 there were seven consecutive successes in the program. It was this string of successes that led to the assessment of a rudimentary orbital bombardment capability. The system tested in this series was designated the SS-X-6 [the provenance of this rather strange designator, which implies an experimental variant of the totally unrelated SS-6 ICBM, is unknown]. The launch vehicle system was believed to be the SL-11.
The capabilities of this system in a FOBS role were assessed as being able to place approximately 7200 pounds in low earth ot·bit and to reenter a 2500 to 3100-pound payload with a circular error probable of between one and three nautical miles at ranges up to about 16,000 nautical miles. This is not as accurate, nor is the payload weight as great, as that which could be delivered by ICBMs or manned bombers. However, the depressed trajectory nature of a FOBS decreased detection ranges while the orbital mode provides a potential for a wide variety of delivery routes and essentially an unlimited delivery range if they modify the tested system.
The system as tested did not appear capable of striking the US as a FOBS. However, if the Russians decreased the payload weight or increased the boost capability of the launch vehicle system, or use a more powerful booster, they could deploy a FOBS which would be capable of striking the US on the first revolution.
The low accuracy o£ such a system would not permit use against hard targets, but it could be used on soft targets. The decreased warning time inherent in this system would make it attractive for use against soft time-sensitive targets. Morover, the possibility that the system could be hidden in hardened SS-9 silos can complicate the US threat assessment problem.
During 1968, the Russians again used the SS-X-6 in a DICBM role. The vehicles were launched from Tyura Tam and impacted in the Pacific. Apogee height o£ these tests was 300 miles, less than the normal apogee height for this system in an ICBM role. These tests continued to cloud the issue on Soviet intent. Clearly, though, the interest and technological capability existed to use space for an offensive weapon system. If the Russians believe the element of surprise which might be available from space weapons could significantly complement their strategic offensive capability, neither high costs nor the space treaty will be likely to deter its use.
In light of the peaceful use of space agreement, the FOBS concept neatly skirted the technicalities of the treaty by being a ground-based rather than an orbital-based nuclear bombardment system. Notwithstanding this loophole, US estimates credited the Soviets with the capabilities to employ the FOBS in a crisis. Soviet secrecy and budgetary camouflage precluded any factual assessment of the full range of USSR space activity and its potential application.
In mid-November 1967, two Soviet Strategic Rocket Forces generals tended to confirm Secretary McNamara’s statement of 3 November. Colonel General Nikolai V. Yegorov, Chief of the Political Department of the SSRF, made references to a rocket that was about 110 feet long and 10 feet in diameter and capable of “unlimited range, pinpoint accuracy and flight-trajectory parameters that make nuclear-missile blows sudden and unavoidable.” Similar descriptions were made of a probable FOBS by Marshal Nikolai I. Krylov, Commander-in-Chief of the SSRF.
The FOBS offered the Soviets a solution to getting around the American BMEWS. While it is not the most accurate or economical weapon system, it does add to the variety of their delivery systems. It seems to fit in as one of several solutions to the Soviet strategists’ problem of insuring the highest degree of success in any possible nuclear war. It tended somewhat to disregard good economics practices, but the Russian defense establishment seemed more interested in results than economics, and the FOBS was funded accordingly.
FOBS had not been flown since 1971, presumably in deference to the treaty barring weapons of mass destruction in space. The principal advantage of the Soviet FOBS was its approach to the United States from the south where the main defensive radars would never pick it up. From its low semi-orbit, it could be called down to impact in about six minutes. While it might have lacked the accuracy to attack hardened targets, the FOBS retained utility in the Soviet arsenal as a coercive weapon effective enough to threaten Strategic Air Command bases and other soft targets. Perhaps more important, by virtue of their early decision to develop an offensive space weapon system, the Soviets have gained valuable experience which could be extended to more advanced offensive systems as their space technology improves through other space programs.
In its developmental phase, at least, when presumably carrying no nuclear payload, FOBS was not considered to be in violation of the space treaty. In reply to an American diplomatic inquiry, the USSR in December 1965 denied any intent to evade the nonorbiting resolution (which subsequently was incorporated in the Space Treaty of January 27, 1967). The Soviet press took the position that the UN resolution barred, not the development or production of orbital missiles, but only the actual placing of warheads in orbit, which in a strict sense was true. While noting that FOBS might be intended to reduce the warning time available through conventional radar, Mr. NcNamara stated that the U.S. development of "over-the-horizon" radar would make it possible to recapture any lost warning time and that, in any event, FOBS did not appear to offer significant military advantages over nonorbiting ICBMs. From the Soviet viewpoint, however, the effort invested in developing FOBS, which reportedly was flight-tested twelve times in the period from September 1966 to October 1968, would tend to suggest that the project was in fact looked upon as promising dividends of some sort, perhaps of a political psychological as weil as a military nature.
As matters stood in early 1969, the Soviet Union had several new strategic delivery systems which were either in the very early stages of deployment or in a preoperational testing stage. These included a Minutemantype silo-emplaced ICBM; a mobile, solid-fuel ICBM; a Polaris-type ballistic-missile submarine; FOBS, and MRV. The critical policy decision, therefore, that must have faced the Soviet leaders at this juncture was whether to go ahead with the procurement and deployment in meaningful numbers of some or all of these new delivery systems.
Article V of the SALT I Treaty that entered into force on 05 December 1994 set forth the activities and systems that were prohibited by the Treaty. Subparagraph (c) of paragraph 18 prohibits the production, testing and deployment of systems, including missiles, for placing nuclear weapons or any other kinds of weapons of mass destruction into Earth orbit or a fraction of any Earth orbit. It may be noted, in this regard, that Article IV of the Outer Space Treaty already banned the orbiting of nuclear weapons, and that Article I of the Treaty Banning Nuclear Weapons Tests in the Atmosphere, In Outer Space and Under Water, already prohibited nuclear explosions in space. Also, this provision would prohibit a fractional orbital bombardment system (FOBS), such as that tested years earlier by the Soviet Union.
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