Launch! Launch! Launch! - Orion Launch Abort System Validated
A spectacular flight test of the Orion launch abort system went off without a hitch May 6 as cheers and applause erupted in the mission control room.
The 500,000-pound-thrust abort motor rocketed the boilerplate crew module and launch abort stack away from launch pad 32E at the U.S. Army White Sands Missile Range, near Los Cruces, N.M. Initial indications are that all systems for steering, separation, stabilization, parachute deployment and landing worked perfectly.
The value of the successful flight was not lost on Dryden's Brent Cobleigh, director of the Dryden Exploration Mission Directorate.
"PA-1 [Pad Abort 1] was a development test. We expected to achieve success on 80 percent of the flight objectives and to learn some lessons on what we didn't get exactly right. What we achieved was 100 percent of the flight objectives, and what we learned was that we had an awesome team," Cobleigh said.
Those are sentiments shared by Laurie Grindle, Dryden project manager for the abort test booster.
"I'm honored to have had the opportunity to work with such an amazing team and hope to continue to do so for an ascent-abort flight. Dryden got involved in this project in 2005, but for most of the team it all started with the first kickoff meeting we had in [room] 113A in January 2006. It's been a long road and often an uphill battle, but the team persevered and accomplished a lot with PA-1. They should be very proud," she said.
And Cathy Bahm, Dryden deputy project manager for the crew module integration and test, is happy to see the payoff of her eight months at White Sands Missile Range.
"It was a great day. It went beyond our hopes. We hoped it would be 80 percent [of goals] and a successful flight. To get a fully successful flight on the first shot says a lot for the capability of this team. All the credit has to go to the team. We would not have been able to achieve anything close to this without the whole team, across the board, stepping up to the challenges every time," Cathy said.
The flight lasted about 135 seconds from launch until the crew module touchdown about a mile north of the launch pad.
The flight was the first fully integrated test of the launch abort system design. Information gathered in the test will help refine design and analysis for future launch abort systems, resulting in safer and more reliable crew escape capability during rocket launch emergencies.
The test involved three motors. An abort motor produced a momentary half-million pounds of thrust to propel the crew module away from the pad. It burned for about six seconds, with the highest impulse in the first 2.5 seconds. The crew module reached a speed of approximately 445 mph in the first three seconds, with a maximum velocity of 539 mph, in its upward trajectory to about 1.2 miles altitude.
The attitude control motor fired simultaneously with the abort motor and steered the vehicle using eight thrusters producing up to 7,000 pounds of thrust. It provided adjustable thrust to keep the crew module on a controlled flight path and reorient the vehicle as the abort system burned out.
The jettison motor, the only one of the three that would be used in all successful rocket launches, pulled the entire launch abort system away from the crew module and cleared the way for parachute deployment and landing. After explosive bolts fired and the jettison motor separated the system from the crew module, the recovery parachute system deployed. The three red-and-white main chutes guided the crew module to landing at 16.2 mph, or 24 feet per second.
The Orion project team has begun to recover all of the test articles from White Sands Missile Range and will be evaluating data over the coming weeks.
The Orion project office at Johnson Space Center in Houston led the launch abort system test team. Langley Research Center, Hampton, Va., designed and built the boilerplate crew module for the test, and Dryden prepared the crew module for integration and led the flight test vehicle integration at White Sands with Lockheed Martin Corp. of Denver, prime contractor to NASA for Orion.
By Jay levine