Minuteman III replacement program wraps up

  • Published
  • By Janae' Daniels
  • AEDC/PA
Arnold Air Force Base, Tenn. --  Arnold Engineering Development Center (AEDC) engineers wrapped up testing of the Propulsion Replacement Program (PRP) for Minuteman III rocket motors in the center's J-6 test cell last week. 

The J-6 facility, which was built in 1994, is used for testing large rocket motors at simulated altitudes up to 100,000 feet above sea level. 

"Since the Minuteman motors were aging, the Air Force has been taking the old motors out of the silo and replacing them with newly manufactured ones," said James Brooks, J-6 program manager. "Minuteman was originally set to be replaced by the Peacekeeper ICBM, but with all the different treaties and the disarmament agreements, the Peacekeeper program was eventually discontinued." 

The PRP test series qualified new designs and motor changes supporting the Minuteman fleet of Intercontinental Ballistic Missiles. 

"The Air Force has taken old Minuteman motors out of the silos, recaptured any of the usable parts, recast the motor propellant, and then replaced the motors back into the missiles," said Brooks. "We started testing the first PQA [production quality assurance] motor in 2001.

"Out of a particular production lot, a randomly selected motor would be tested at AEDC to make sure it met quality specifications," Brooks explained. 

As part of the PRP, ATK Launch Systems manufactured approximately 600 stage 2 and stage 3 motors to replace the motors in the Minuteman III fleet. 

According to Brooks, AEDC tested the following motors in J-6: 

· 17 stage 2 PQA motors 
· 1 stage 2 qualification motor 
· 17 stage 3 PQA motors 
· 1 stage 3 qualification motor 
· 1 stage 3 case qualification motor 
· 2 stage 3 nozzle qualification motors 
· The PRP program also funded the first seven aging surveillance tests (three stage 2 and four stage 3)

 The next test phase will be aging surveillance of the motors. 

"Once you get the motors out on the fleet, you want to continually check and see if the performance is degrading over time," Brooks said. "So the Air Force will install the motors out on the fleet, leave them in the silo for awhile, and then randomly select a missile motor for aging surveillance testing. The selected missile will be removed from the silo, disassembled, and stage 2 and 3 motors will be sent to AEDC for testing." 

The surveillance requirement for aging motors is to extend the service life of the Minuteman III rocket motors through 2020. 

According to Lt. Col. James Colebank, commander of the 718th Test Squadron, "The test and evaluation of Minuteman rocket motors in the J-6 facility is crucial to the long-term viability of the ICBM fleet and to assure the United States maintains a credible nuclear deterrent." 

The 718th Test Squadron is responsible for test and evaluation of space and missile systems at AEDC.