A leaky valve within SpaceX’s launch-abort system caused an explosion during testing three months ago and requires design changes, making it tougher for the company to fly astronauts this year as planned.
The April 20 incident at Cape Canaveral Air Station in Florida destroyed a SpaceX Crew Dragon capsule and was a setback for the Elon Musk-led company, which has a contract to fly NASA astronauts to and from the International Space Station. It’s also a blow to the U.S. government’s public-private effort to ferry Americans back into space without having to rely on Russian rockets.
During a call with reporters Monday, SpaceX said investigators traced the cause of the blast to a high-pressure valve within the thruster system of its rocket engine, which the company calls SuperDraco. The thruster system is designed to rapidly fire the crew module away from the rocket in cases of emergency.
But a leaky component allowed liquid oxidizer to enter high-pressure tubes, then escape through a titanium check valve at high speed, leading to the explosion, said Hans Koenigsmann, a SpaceX vice president.
The test incident was a stumbling block for NASA’s Commercial Crew Program, in which SpaceX and Boeing Co. are vying to be the first companies to ferry astronauts. Both had been expected to fly two test missions to the ISS -- with and without astronauts -- by year’s end. That schedule now appears to be slipping into 2020.
“I don’t think it’s impossible but it’s getting increasingly difficult” for a SpaceX flight with astronauts this year, Koenigsmann said.
SpaceX completed its first test flight to and from the space station in March. Boeing’s CST-100 Starliner has to complete a pad abort test this summer and then its first test flight. The latter flight to the ISS is tentatively scheduled for August.