ORBUS rocket motor undergoes successful test firing at J-6

  • Published
  • By Philip J. Lorenz III
ARNOLD AIR FORCE BASE, TENN --  The U.S. Air Force's Arnold Engineering Development Center (AEDC) successfully test-fired an ORBUS 1A rocket motor under simulated high-altitude conditions at the center's J-6 Large Rocket Motor Test Facility, providing critical support for the second and third stage power plant of the Missile Defense Agency's (MDA) Ground-Based Interceptor (GBI) missile.
The GBI is the weapon component of the Ground-Based Midcourse Defense system, and is the long-range interceptor of the overall Ballistic Missile Defense System (BMDS). The BMDS is an integrated, "layered" system for defending the U.S. homeland, our deployed forces overseas and our allies from ballistic missiles of all ranges, during any phase of their flight-boost, midcourse and terminal. The BMDS now in development will consist of ground and sea-based interceptors, a directed energy aircraft (Airborne Laser) and numerous radars and sensors integrated with a command, control, battle management and communication infrastructure.
The GBI's payload will be an Exoatmospheric Kill Vehicle equipped with a high-sensitivity infrared seeker and an agile-divert system to support the intercepts of threats at very high closing velocities. This is a "hit-to-kill" technology that uses only the force of a direct collision with the target missile warhead, using no explosives. A number of GBI's are currently deployed in Alaska and California in preparation for beginning defensive operations after on-going training, rules of engagement development and additional testing are complete.
The GBI missile's second /third stage rocket motor, built by Alliant Techsystems (ATK) in Elkton, Md., underwent the qualification testing because the company recently took over the production of the upper-stage components of the GBI missile from Pratt & Whitney.
"The ORBUS motor has been around for quite a long time," explained 2nd Lt. Timothy Higley, a test project manager for the space and missiles division at AEDC. "It's not a new system; it's basically being revised and reused for the GBI. Now that they (ATK) are beginning to build these motors, they have to be qualified as a vendor to verify they can reliably produce these motors and meet all the specs."
He added, "This (rocket motor) is the first one of its type we've tested in J-6. Previously, during the 1990s, we had performed qualification testing on an earlier version of this rocket motor in AEDC's rocket development test cell J-5."
Lieutenant Higley said the reasoning behind the change of testing location is the system at J-6 is a better facility from both a performance and safety standpoint.
"J-6 is a newer rocket testing facility," he said. "It's larger, has a significant blast wall, the increased distance from other buildings at the Center, as well as some improved features inside the test cell, including the ability to pump down the pressure and isolate it from the plant."