Minuteman III missile

The US Air Force’s (USAF) Minuteman III propulsion system rocket engine (PSRE) has successfully completed testing at Nasa’s White Sands Testing Facility in Las Cruces, New Mexico, US.

Supported by Northrop Grumman, the testing represents the last of seven product quality assurance (PQA) static tests under the PSRE life-extension programme (LEP).

A full mission duty ground static test, PQA trial is conducted in Nasa’s altitude test cell for verification of the PSRE’s quality following its refurbishment under the LEP programme.

Northrop Grumman ICBM Prime Integration Contract vice-president and programme manager Tony Spehar said: "These PSRE tests have ensured the reliability of the nation’s deployed Minuteman fleet."

The testing was also supported by the USAF, and other ICBM team members, including Aerojet and Boeing.

Manufactured by Aerojet, PSRE is the liquid post-boost upper stage of the Minuteman III intercontinental ballistic missile (ICBM), and is designed to provide the missile with post-boost propulsion to slightly adjust the trajectory.

Managed under a joint partnership between Northrop and the USAF, the PSRE LEP programme involves refurbishment of the entire Minuteman III PSRE fleet to help extend its operational life through to 2030.

"Supported by Northrop Grumman, the testing represents the final of seven product quality assurance static tests under the PSRE life-extension programme."

Until last month, the programme had delivered approximately 558 PSREs to the USAF.

Manufactured by Boeing, the LGM-30G Minuteman III is a ground-based ICBM designed to deliver nuclear warheads, and represents one component of a nuclear triad that is complemented by the Trident submarine-launched ballistic missile (SLBM) and by nuclear weapons carried by long-range strategic bomber aircraft.

The missile entered operational service with the USAF in 1968, and currently 450 Minuteman-III ICBMs are located in silos at the 90th Missile Wing at Warren AFB in Wyoming, the 341st Missile Wing at Malmstrom AFB in Montana, and the 91st Missile Wing at Minot AFB in North Dakota, US.

Image: A LGM-30 Minuteman III missile being launched. Photo: courtesy of US Air Force.

Defence Technology