Orion abort system passes in-flight abort test

KENNEDY SPACE CENTER, Fla. — NASA successfully demonstrated the abort system for its Orion spacecraft July 2 during a dramatic in-flight test of the system at Cape Canaveral.

A refurbished Peacekeeper rocket motor lifted off from Space Launch Complex 46 at Cape Canaveral Air Force Station lifted off at 7 a.m. Eastern, carrying a boilerplate Orion module and its launch abort system (LAS) on a mission known as Abort Ascent 2 (AA-2).

Fifty-five seconds after liftoff, controllers activated the LAS at an altitude of nearly 9,500 meters and speed of Mach 1.3. The LAS used three sets of motors to pull the Orion capsule away from the booster, reorient the capsule and then jettison itself from the capsule.

The Orion flown on this test was a “simplified version” of the spacecraft with the same mass and dimensions, but without any of the internal subsystems. The capsule was built by the agency by teams at Armstrong Flight Research Center, Johnson Space Center and Langley Research Center, said Jenny Devolites, the AA-2 test conductor, at a pre-test press conference here July 1.

The boilerplate Orion was not equipped with parachutes, which she said had been sufficiently tested elsewhere. The capsule did eject 12 data recorders designed to be recovered from the ocean as backups to the data transmitted during the test. She estimated the capsule would hit the ocean at about 500 kilometers per hour. “We are not expecting it to stay intact when it hits,” she said.

AA-2 liftoff
The refurbished Peacekeeper booster carrying the Orion capsule and launch abort system lifts off July 2 from Cape Canaveral Air Force Station. Credit: SpaceNews/Jeff Foust

The AA-2 test was designed to simulate conditions during maximum dynamic pressure, or “Max Q,” during a flight of the Space Launch System. It sets one limit of the conditions the LAS has to operate in to safely propel an Orion away from an SLS. A pad abort test, conducted in 2010, set the other limit for the system.

Mark Kirasich, NASA’s Orion program manager, said the AA-2 test would be more difficult than that earlier pad abort test because of the aerodynamic forces on the vehicle. “That how we picked the test points for this, the most challenging part of the ascent that Orion will ever see,” he said at the briefing.

NASA made only minor modifications to the LAS since that earlier pad abort test. “When we flew the pad abort test several years ago, we did note several items we wanted to improve upon,” he said. That included making the abort motor somewhat smaller since the system didn’t need as much thrust as originally planned.

The version of the LAS flown on AA-2 is designed to be identical to the ones that will be used on future crewed Orion flights, starting with Artemis-2 in 2022. “The intent is that this is the production LAS,” he said.

The LAS has received more attention since the aborted launch of the Soyuz MS-10 spacecraft in October 2018, when abort motors had to pull the spacecraft away from the Soyuz launch vehicle after a booster failed to separately cleanly from the rocket’s core stage. The Soyuz landed safely downrange from the Baikonur Cosmodrome and its crew, Alexey Ovchinin and Nick Hague, flew to the station on another Soyuz mission earlier this year.

“We have to prepare for this even though it’s a low likelihood of happening,” said NASA astronaut Randy Bresnik at the pre-test briefing. Even though it had been 35 years since the previous Soyuz abort, he said the training and preparations ensured the crew was able to make it back safely. “That was definitely a good message to all of us that, hey, this is serious stuff.”

The AA-2 test, he added, “is huge for us to be able to have that confidence that the whole system we’ve designed works.”

source: spacenews.com