WASHINGTON — SpaceX has delayed by several months a pair of test flights of its Crew Dragon spacecraft being developed for NASA's commercial crew program, in part because of a Falcon 9 pad explosion in September.
A revised schedule released by NASA Dec. 12stated that an uncrewed test flight of the spacecraft, previously scheduled for May 2017, is now planned for November 2017. A crewed test flight, carrying two NASA astronauts, has been delayed from August 2017 to May 2018.
The NASA statement did not give a reason for the revised schedule other than it reflected a "fourth quarter update" from SpaceX. Kathy Lueders, NASA commercial crew program manager, said at a Nov. 14 meeting of the NASA Advisory Council's human exploration and operations committee that schedules are formally changed at quarterly review meetings with commercial crew companies, and that at the time the fourth quarter meeting with SpaceX, the first since the pad explosion, had not yet taken place. [SpaceX's Crew Dragon Space Taxi in Pictures]
A delay of some kind was expected given the Sept. 1 explosion of a Falcon 9 on the pad at Cape Canaveral, Florida, during preparations for a static-fire test. The Falcon 9 has been grounded since that accident, with a return to flight now scheduled for no sooner than early January.
SpaceX spokesman Phil Larson confirmed the delayed test schedule, although giving the revised dates only in the quarter they are planned: the fourth quarter of 2017 for the uncrewed test flight and the second quarter of 2018 for the crewed test flight.
"We are carefully assessing our designs, systems, and processes taking into account the lessons learned and corrective actions identified," SpaceX said in a statement, referring to the failure investigation that the company says it is now finalizing. "Our schedule reflects the additional time needed for this assessment and implementation."
The SpaceX statement also addresses another criticism that arose after the accident. At an Oct. 31 meeting of NASA's International Space Station Advisory Committee, its chairman, former astronaut Thomas Stafford, criticized NASA for not responding to a letter the committee send in December 2015 regarding SpaceX's plans to have the crew on board the Dragon spacecraft while the Falcon 9 is being fueled. That plan, required by SpaceX's need to fuel the Falcon 9 with "supercooled" propellants shortly before launch, is "contrary to booster safety criteria that has been in place for over 50 years," Stafford wrote in the letter.
SpaceX said that it has worked with NASA to perform "a detailed safety analysis of all potential hazards" involved in this fueling process, with a report approved by NASA's Safety Technical Review Board in July. That report, the company said, identified various controls it will implement to address those hazards. "As needed, any additional controls will be put in place to ensure crew safety," the company said.
SpaceX added that company officials recently met with Stafford and his committee "to provide them detailed information on our approach and answer a number of questions," but did not disclose what response, if any, Stafford's committee had to that information. "SpaceX and NASA will continue our ongoing assessment while keeping the committee apprised of our progress."
The revised schedule comes two months after Boeing, the other company with a NASA commercial crew contract, delayed its schedule of test flights of the CST-100 Starliner spacecraft by six months. That revised schedule, confirmed by NASA Dec. 12, calls for an uncrewed CST-100 mission in June 2018, followed by a crewed test flight in August 2018.
The new schedules give NASA little margin for certifying either vehicle and beginning regular crewed flights to the ISS with them before the agency's current contract with Russia for Soyuz flights expires at the end of 2018. However, NASA has not stated any plans to extend its Soyuz contract, and agency officials have said in recent months that it would be too late to sign a deal now for 2019 Soyuz flights, citing a three-year lead time for Soyuz production.
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