The second ground test of a full-scale attitude control motor for the launch abort system, designed for the Orion crew exploration vehicle, was conducted March 17 at Alliant Techsystems’ facility in Elkton, Md. It was the seventh in a series of ground tests of the control motor system.
The motor is designed to keep a crew module on a controlled flight path in the event it needs to jettison and steer away from a launch rocket in an emergency.
The control motor consists of a solid propellant gas generator, with eight proportional valves equally spaced around the outside of the three-foot diameter motor.
Together, the valves can exert up to 7,000 pounds of steering force to the vehicle in any direction on command from the crew module. The entire abort system is scheduled to be demonstrated this spring during a Pad Abort-1 flight test at the U.S. Army’s White Sands Missile Range in New Mexico, to continue to refine technologies for crew safety systems.
The Marshall Space Flight Center is responsible for providing propulsion oversight during the development of the three motors, which includes an abort motor that pulls the Orion capsule from danger, an attitude control motor to provide directional control and the jettison motor that separates the system from the crew module.
In the event of a launch failure, the main abort motor will ignite, producing nearly a half-million pounds of thrust within milliseconds, and pull the mockup crew module from the platform.
Once the crew module has been reoriented for landing, the launch abort system will be jettisoned, and parachutes will slow the capsule’s descent to a safe landing. Marshall also has supporting roles in thermal, structures, mechanisms, avionics, systems engineering, flight test and ground operations.
The Langley Research Center in Hampton, Va., is responsible for overall program management for the launch abort system design and development effort with team members from the Marshall Center. Langley’s Launch Abort System Office performs this function as part of the Orion Project Office located at the Johnson Space Center in Houston. Alliant Techsystems is under contract with Lockheed Martin Co., NASA’s prime contractor for Orion, to develop and test the attitude control motor.
