Northrop Grumman [NOC] and ATK [ATK] said recently they successfully ground-tested a Minuteman III Stage 1 solid rocket motor for the Air Force as part of the Minuteman Solid Rocket Motor Warm Line (SRMWL) program at ATK’s test facility in Utah.

This test was the second Production Quality Assurance (PQA) ground test of the SRMWL Stage 1.

The first Stage 1 PQA was successfully tested on March 24, 2011.

The SRMWL is designed to sustain critical propulsion-related skills to ensure the weapon system can be sustained.

The Minuteman III program began in 1966 and currently maintains 450 missiles deployed at three missile wings.

“We prepare for and assess every ICBM test very rigorously, and the success of this Stage 1 test provides one more point of assurance of the integrity and reliability of the ICBM weapon system today and the solid rocket motor industrial base for the years to come,” said Tony Spehar, vice-president of Northrop Grumman’s Missile Systems business unit.

Northrop Grumman is the ICBM prime contractor and responsible for overall sustainment of the ICBM weapon system.

As part of the SRMWL program, up to 10 motor sets over two years will be manufactured by ATK under contract to Northrop Grumman at ATK facilities in Utah.

The objective of the SRMWL’s PQA testing is to demonstrate the motors perform as designed.

Each of the three stages is tested every year. Ground tests for Stage 2 and 3 are conducted in altitude chambers at Air Force’s Arnold Engineering Development Center in Tennessee and each was successfully tested this past summer.

“This successful test demonstrates that the motors produced under the warm line contract are fully representative of deployed first stage ICBM motors,” said Scott Lehr, ATK Aerospace Systems vice president and general manager of Strategic and Commercial Systems. The warm line program also maintains the critical skills, infrastructure and supplier base necessary to produce ICBM propulsion hardware in the future.”

The refurbished Stage 1 case used in this test originally entered operational inventory in January 1961. ATK has manufactured over 4,000 Minuteman motors over the life of the program. The company recently completed a successful 10-year Minuteman Propulsion Replacement Program that produced approximately 1,800 re-manufactured motors.