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Ascent Abort 2 completes Orion test program. (July 2, 2019)

Reminiscent of the early 1960s tests for the Mercury and Apollo programs, NASA performed a three-minute flight test of the Orion Launch Escape System early Tuesday morning, July 2. The Ascent Abort 2 mission lifted off from LC-46 at 7am EDT utilizing a converted Peacekeeper missile, dubbed the Abort Test Motor.

Fifty-one seconds after liftoff at around 31,000 feet in altitude, the Launch Escape System pulled the boilerplate Orion capsule away from the vehicle with over 400,000 pounds of force. Small control motors atop the system reoriented the capsule towards the Earth, and 17 seconds later the capsule was jettisoned. Orion reached a maximum altitude of just under 44,000 feet before plummeting towards the Atlantic Ocean. Maximum speed was around 1,000 miles per hour.

Previous tests of the capsule’s recovery systems gave engineers the option exclude parachutes on AA-2. The boilerplate capsule and booster were designed to break apart and sink in the Atlantic ocean once the test was complete. NASA estimates the components impacted the ocean at around 350 miles per hour roughly ten miles offshore.

During the capsule’s descent, twelve Electronic Data Recorders were ejected containing test data gathered by over 890 sensors. These were designed to float and be recovered via boat following the test. 

Diagram of the AA-2 vehicle showing the two major components, the Abort Test Booster and the Flight Test Article. (NASA)

The Abort Test Motor, launch vehicle for AA-2, utilized a converted SR-118 solid rocket motor originally designed for the Peacekeeper Intercontinental Ballistic Missile. An aerodynamic shell was placed around the motor to integrate it with the Orion capsule, which was over twice its width. 

Due to the sheer power of the Peacekeeper first stage, 110,000 pounds of steel ballast were added in order to slow the vehicle’s ascent. This ensured that the proper test conditions could be met at the correct portion of the flight profile. According to the AA-2 test conductor Jenny Devolites the test performed “flawlessly,” and Orion program manager Mark Kirasich stated that “everything we’ve seen so far looks great.”

Similar tests were performed by NASA during the early 1960s as part of the Mercury and Apollo programs, which also utilized pull-type abort systems. Eight flights of the Little Joe I booster tested Mercury’s escape system between 1959 and 1960, while five flights of the larger Little Joe II tested Apollo’s escape system between 1963 and 1966. However, unlike AA-2, those flights occurred from Wallops Island, Virginia and the White Sands Missile Range in New Mexico, not Cape Canaveral. Additionally, the Little Joe launch vehicles were designed in-house, while AA-2 utilizes a former ICBM motor modified for the mission.

In-flight abort tests for NASA’s Mercury, Apollo, and Artemis programs. (NASA)

Orion’s LES features upgraded technology and the addition of attitude control motors, expanding the capabilities of the abort system from that of the Apollo era.

Tuesday’s flight was the final significant test of an Orion spacecraft system prior to its first flight on the SLS rocket. That mission, dubbed Artemis-1, is slated to occur in mid-2020 without any crew. Artemis-2 will be the first integrated flight with crew aboard.

Watch a replay of the Ascent Abort 2 flight by clicking here.

NASA’s published different angles of the AA-2 flight that can be seen here.

NASA’s Ascent Abort 2 launches from LC-46 at Cape Canaveral Air Force Station, July 2, 2019. AA-2 tested the Orion capsule’s Launch Escape System during flight conditions.  The 96 foot vehicle was powered by a Northrup Grumman SR-118 solid rocket motor, a surplus first stage from the Peacekeeper ICBM program of the U.S. Air Force. Three minutes after liftoff, the vehicle’s three components impacted the Atlantic ocean roughly ten miles off shore of Cape Canaveral, concluding the flight test.

Click here for our coverage of the AA-2 test.