Falcon 9 – SpaceX
The explosion of SpaceX’s Falcon 9 rocket mere minutes after launch on Sunday was strike one for US hopes of rebooting crewed space flight: this is the very type of rocket the company wants to use to send people into space in 2017.
“You want a really, really reliable rocket before you put people on it,” says Jonathan McDowell of Harvard University. Now that SpaceX has lost its perfect launch record with this rocket, it will need to quickly convince people that the rocket can be trusted, he says. “Yesterday [the Falcon 9] was 18 for 18 and looking pretty good. Now it is 18 for 19. That’s a 5 percent failure rate.”
But if another 10 launches of Falcon 9 proceed without incident, that will bring the failure rate to 3.5 per cent, which could be acceptable, he says.
Among almost two tonnes of supplies and equipment in the Dragon capsule atop the rocket were two docking stations, intended for Space X to dock its crewed Dragon capsule to the International Space Station (ISS). It was also carrying several plant and animal experiments.
The failure shouldn’t force a delay in plans to launch the first crewed space mission on US soil since 2011, said William Gerstenmaier, NASA’s associate administrator for human exploration, at a press conference. “It could help us to nail down designs and move forward,” he said.
The Falcon 9 rocket exploded 2 minutes and 19 seconds after launch from Cape Canaveral in Florida. In a tweet, Elon Musk said it was triggered by too much pressure in a liquid oxygen tank in the upper stage of the rocket, adding: “Data suggests counterintuitive cause,” without further explanation.
“It was in the upper part of the rocket, not the part that was firing at the time,” says McDowell. “That’s representative of a class of failures associated with structural and aerodynamic problems.”
McDowell says there are probably no safety procedures that SpaceX would undertake during a crewed flight that could have prevented this explosion. “But Crew Dragon would have an escape system that would save the capsule, so you wouldn’t have killed the crew.”
Another SpaceX rocket spectacularly exploded during an attempt at landing it as part of a plan to make the Falcon 9 reusable. That attempt was highly experimental and appears unrelated to yesterday’s explosion during launch.
“SpaceX have been careful to do the experimental tests after the operational part of each mission is over,” says McDowell. “So playing with new stuff in the stage 1 re-entry phase shouldn’t make the all-important launch phase more dangerous.”
The explosion also follows a number of failures of other ISS supply rockets.
“There’s really no commonality across these three events other than the fact that it’s space, and it’s difficult to go fly,” said Gerstenmaier. “We’re essentially operating systems at the edge of their ability to perform and operate.”
Watching from on board the ISS, US astronaut Scott Kelly summed up the sentiment in a tweet: “Space is hard.”
Syndicated Content: Michael Slezak, New Scientist
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