SpaceX Pad Abort Test Still On For Wednesday-UPDATE

UPDATE, May 5, 10:15 pm ET:   NASA and Space X announced this evening that the launch window will open at 9:00 am ET instead of 7:00 am ET and close at 4:00 pm ET rather than 2:30 pm ET.

ORIGINAL STORY, May 5, 5:06 pm ET:  The pad abort test of SpaceX’s Dragon capsule is still on schedule for tomorrow, May 6, 2015.  The window is open from 7:00 am – 2:30 pm ET.  The weather is 70 percent favorable.

The test is part of SpaceX’s Commercial Crew Integrated Capability (CCiCAP) agreement with NASA to develop a crew version of its Dragon spacecraft for taking astronauts to and from the International Space Station (ISS).  SpaceX also hopes there will be a market for taking other people to and from space, but in this case the test is directly related to its goal of servicing the ISS for NASA.

The test does not involve the use of a Falcon 9 rocket.  Instead, it is a test of the integrated abort system that is part of the Dragon capsule itself.  Unlike the “escape towers” used on the Mercury, Gemini and Apollo missions of the 1960s and 1970s, the Dragon system uses eight “Super Draco” liquid fueled engines in the sides of the spacecraft.  Thus they are with the spacecraft all the way up to orbit so the capsule could return to Earth in an emergency throughout the ride.  The earlier systems were jettisoned after the capsules reached a certain altitude.

This is the first time SpaceX will fire eight Super Draco engines at once.  The most that have been fired together in the past was two.  The engines are designed into the spacecraft because SpaceX hopes eventually to use them to land Dragons back on Earth propulsively, rather than using parachutes and dropping into the ocean.  Thus they serve two functions — as an abort system on the way up and, if all goes well and they are not needed for that purpose, to land the spacecraft gently on terra firma at the end of the mission.

The entire test is expected to last for only 1.5 minutes.   SpaceX’s Hans Koenigsmann, vice president of mission assurance, joked at a press conference on Friday that if a viewer waits to hear the sound of the engines firing, the test will already be over.

The engines will fire for 6 seconds, followed by a 20 second coast phase as the Dragon capsule rises to about 5,000 feet altitude.  It will then descend under parachutes to land in the Atlantic Ocean about one mile offshore.  It will be retrieved and returned to SpaceX’s McGregor, TX facility for study.   An instrumented dummy will be aboard to measure g forces and other parameters that an astronaut would experience.   When asked if the dummy had a name, Koenigsmann quickly replied “yes” on Friday, and said it was Buster.  The company has since backed away from that name, however, since it is associated with the TV program MythBusters.  Saying there will be a dummy aboard, but his name is not Buster, the company lightheartedly says on its website that “Buster the Dummy already works for a great show you may have heard of called MythBusters.  Our dummy prefers to remain anonymous for the time being.”

Koenigsmann urged patience, noting the multi-hour launch window for such a brief test.   He said they would go when they were ready to go.  The only weather constraint is onshore winds.

He and NASA’s Jon Cowart both stressed that the test will be valuable no matter the result since the whole point is that it is a development flight.  An in-flight abort test using the same capsule launched by a Falcon 9 rocket is planned later this year.  The date will not be set until the results of this test are known.  That launch will be from Vandenberg Air Force Base, CA, Koenigsmann said.

SpaceX posted a fact sheet yesterday entitled “5 Things To Know About SpaceX’s Pad Abort Test.”

Wednesday’s test will be covered by NASA TV (and possibly on SpaceX’s website as well).