Space Command Study on Future ICBM Nearly Complete
Aviation Week & Space Technology 08/01/2005, page 49
Amy Butler Washington
Air Force planners are seeking better accuracy, reliability in a next-generation ICBM
Shopping for Deterrence
With its Peacekeeper force nearly deactivated and its Minuteman III fleet expected to expire in a little more than 10 years, the Pentagon is looking for a new intercontinental ballistic missile for the strategic nuclear deterrence mission.
At the top of the wish list for the new weapon are flexible targeting, high reliability, longer range and better targeting precision, according to Brig. Gen. Mark Shackelford, requirements director at Air Force Space Command. So far, industry has offered roughly 30 different concepts, he says.
A study of alternatives, led by the command, should be complete by October. A new review of "prompt" global-strike options is set to begin on its heels. The former is focused solely on a nuclear weapon delivery system; the latter is expected to find ways to expand the conventional reach of the Pentagon, especially to hit hard and deeply buried targets like command bunkers. Shackelford says U.S. Strategic Command wants to be able to strike anywhere around the globe conventionally with as prompt a response as its nuclear-tipped ICBMs. Although the specifics are classified, the advertised reaction time of the ICBM force is about 30 min.
The Minuteman III fleet's expected expiration in 2018 is prompting the Pentagon to begin assessing its options for a future system. Upkeep of the ICBM force can reach up to $150 million annually, and planners are hoping to find a solution that will be cheaper.
Flexible targeting is especially critical, as the group of nations possessing or developing long-range and surprise-strike capabilities against the U.S. has grown since the development of the Peacekeeper in the 1970s. The future system will likely use the existing silos in a handful of western states because the Pentagon is unlikely to fund an entirely new infrastructure in the current fiscal environment. In recent years, some senior leaders suggested a mobile system could be needed, but Shackelford says the command has found the existing system sufficient.
AIR FORCE SPACE Command intends to insert money for the ICBM replacement in the Fiscal 2008 budget in order to field a system to relieve the Minuteman III fleet in 2018. A confluence of aging equipment and attrition due to a mandatory three tests per year will put the 500-strong Minuteman III force at a critical low point then despite ongoing propulsion and guidance system upgrades.
Meanwhile, the command is preparing for its next big analysis of alternatives which will review options for a global strike capability. As the nuclear arsenal is thought to have held the Soviets at bay due to the threat of mutually assured destruction, the Pentagon is pursing a new form of deterrence using quick-reaction, long-range conventionally armed weapons. The theory behind the capability is that no enemy can safely hide in a bunker, for example, and U.S. resolve to destroy any target conventionally could deter some potential aggressors from acting.
There could be some overlap in the two future systems, given the similarity of the notional requirements. Indeed, some options include using ICBMs--refurbished old ones or new systems--without their nuclear warheads for a conventional mission. To avoid any chance of a misperception that the U.S. is launching a nuclear ICBM when actually dispatching a conventional missile, one option would be to operate the less destructive ones from the launch facilities on either coast, says Shackelford.
It is likely the prompt-strike system will fly through space, as air-breathing options and hypersonics are not developed well enough to provide a reliable solution. "If you really want to attack a time-critical target, then the solution pretty much drives you to a space-like application," says Shackelford. Off the table, however, is basing weapons in space, which is prohibited by treaties.
Improving accuracy is not expected to be a major hurdle in either system, Shackelford says. However, it's more critical to ensure precision in a conventionally armed system that cannot rely on the massive blast radius of a nuclear explosion to compensate for inaccuracy. The future system can take advantage of the GPS network, which has provided consistent precision for air-launched systems and was not fully fielded when the Peacekeeper came into service.
SOME POTENTIAL hurdles for the conventionally armed system include how to time the fuze and how to control its speed. Fuzing will have to occur on a precise schedule to hit a buried target, for example. And, it must be flexible so operators can hit targets at varied distances below soil and concrete. Furthermore, Shackelford says engineers will have to explore how to actually slow down the reentry vehicles. Impact at too high a speed could render the explosive power of the warhead useless.
It will likely take about 24 months to complete the analysis for prompt-strike options, although Space Command officials hope to accelerate it as much as possible.
