Video: Preview of dramatic Crew Dragon In-Flight Abort Test

SpaceX’s final planned Crew Dragon test flight before astronauts ride the commercial spaceship into orbit is scheduled for Saturday, when an unpiloted crew capsule will fire off the top of a Falcon 9 rocket shortly after launch from the Kennedy Space Center in Florida to test the craft’s in-flight emergency escape capability.

This video illustrates the timeline of the in-flight abort test, which is scheduled to begin during a four-hour window opening at 8 a.m. EST (1300 GMT) Saturday.

A Falcon 9 rocket will lift off from pad 39A at the Florida launch base and arc toward the east, simulating a crewed mission for the first minute-and-a-half of the flight.

After reaching a predetermined supersonic velocity threshold, the Falcon 9 will shut down its nine Merlin 1D first stage engines to simulate a launch failure. Then eight SuperDraco thrusters fixed to the circumference of the Crew Dragon spacecraft will ignite to quickly propel the spaceship away from the top of the Falcon 9 at an altitude of about 65,000 feet (about 20 kilometers).

The SuperDraco thrusters will rapidly power up to generate nearly 130,000 pounds of thrust. The launch escape engines will push the Crew Dragon well clear of the Falcon 9 rocket, which is expected to break apart due to aerodynamic forces after the capsule’s abort maneuver.

After the SuperDraco engines shut down, the Crew Dragon will coast to an apogee of about 138,000 feet (42 kilometers), then jettison its no-longer-needed trunk section. The capsule will deploy parachutes to slow for splashdown in the Atlantic Ocean around 20 miles (32 kilometers) east of the Florida coast, where teams from SpaceX and the U.S. Air Force will practice search-and-rescue techniques before retrieving the Crew Dragon for return to port.

The test flight Saturday is designed to verify the Crew Dragon’s ability to carry astronauts away from a failing launcher, a key part of the SpaceX ship’s safety system.

SpaceX developed the Crew Dragon under a multibillion-dollar contract with NASA to ferry astronauts to and from the International Space Station. NASA also awarded Boeing a similar contract to develop the Starliner crew capsule, which is also awaiting its first crewed mission — giving the agency two vehicles to help end U.S. reliance on Russian Soyuz spacecraft for crew transportation to the station.

SpaceX conducted the first Crew Dragon test flight to the space station last March, but engineers ran into trouble in April, when the capsule exploded during a ground test. The accident occurred moments before a ground test-firing of the Crew Dragon’s SuperDraco abort engines and resulted in no injuries, but it destroyed the spaceship that just returned from the space station.

Engineers say they resolved the problem that led to the explosion, and SpaceX performed a similar ground firing of the SuperDraco engines on a new Crew Dragon vehicle in November, setting the stage for the in-flight abort test.

Assuming the launch escape test goes well Saturday, SpaceX could be on pace to launch two NASA astronauts on the next Crew Dragon test flight in the next few months

Astronauts Doug Hurley and Bob Behnken are training for the Crew Dragon mission, designated Demo-2. Hurley and Behnken will dock with the space station before returning with the Crew Dragon for a parachute-assisted splashdown in the Atlantic Ocean.

The Demo-2 mission will be a precursor to the final certification of the Crew Dragon spacecraft to begin regular crew rotation flights to the space station.

Email the author.

Follow Stephen Clark on Twitter: @StephenClark1.