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posted by chromas on Monday August 13 2018, @04:00PM   Printer-friendly

The NASA manager overseeing development of Boeing and SpaceX's commercial crew ferry ships says the space agency has approved SpaceX's proposal to strap in astronauts atop Falcon 9 rockets, then fuel the launchers in the final hour of the countdown as the company does for its uncrewed missions.

The "load-and-go" procedure has become standard for SpaceX's satellite launches, in which an automatic countdown sequencer commands chilled kerosene and cryogenic liquid oxygen to flow into the Falcon 9 rocket in the final minutes before liftoff.

[...] SpaceX's "load-and-go" procedure raised concerns after a Falcon 9 rocket exploded on its launch pad at Cape Canaveral in September 2016. The fiery accident occurred in the final minutes of a countdown while propellants were flowing into the rocket before a hold-down engine firing, destroying the launcher and an Israeli-owned communications satellite on-board.

Officials from SpaceX said the Crew Dragon's escape system, comprising a set of high-thrust SuperDraco engines around the circumference of the capsule, would be quick enough to push the spacecraft and its crew away from such an explosion during fueling.

The abort thrusters will be activated and armed before fueling of the Falcon 9 during crewed launches.

SpaceX plans an unmanned, in-flight abort test prior to the first crewed flight, which is tentatively scheduled for April 2019.

Source: https://spaceflightnow.com/2018/08/09/nasa-signs-off-on-spacexs-load-and-go-procedure-for-crew-launches/


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  • (Score: 2, Interesting) by tftp on Monday August 13 2018, @06:04PM (3 children)

    by tftp (806) on Monday August 13 2018, @06:04PM (#721072) Homepage
    An already loaded rocket is static. Nothing is happening. However fueling process is dynamic and had already caused an incident. Statistic shows that there was no loss of crew while climbing into a fueled rocket. Statistic will probably show that sitting in a well designed rocket during fueling is also safe enough. The crew escape systems are simple and well tested. So probably there is no big difference. Over long time there might be preference toward preloading the crew because explosion during fueling will not kill the crew, but explosion of fueled rocket will kill the crew and the workers.
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  • (Score: 3, Informative) by slap on Tuesday August 14 2018, @12:48AM

    by slap (5764) on Tuesday August 14 2018, @12:48AM (#721190)

    "An already loaded rocket is static."

    Actually, they continually add more liquid oxygen (and liquid hydrogen for those rockets that use it) as the liquids boil off - the tanks are not refrigerated and have minimal or no insulation.

  • (Score: 1) by khallow on Tuesday August 14 2018, @09:47AM

    by khallow (3766) Subscriber Badge on Tuesday August 14 2018, @09:47AM (#721302) Journal

    An already loaded rocket is static.

    No such thing when you're dealing with cryogenic temperature fuels. And they had to delay many a Shuttle launch due to hydrogen leaks.

    Statistic shows that there was no loss of crew while climbing into a fueled rocket.

    Yet.

  • (Score: 2) by VLM on Tuesday August 14 2018, @12:38PM

    by VLM (445) on Tuesday August 14 2018, @12:38PM (#721339)

    NASA is political and you're missing the CYA component. At the congressional hearings, "it was loaded and ready to go" will sell better after a pre-launch accident.

    Also really old timers or hard core space dudes will remember Apollo 1 and its fire and more importantly its investigation. They're worried the fueling process will start a fire and cook the crew in some unanticipated incident, not in an anticipated incident. You can't cook the crew in a completely unanticipated fueling accident if the crew is sleeping in their beds 20 miles away while fueling, and in the congressional investigation its hard to hand wave away sound bites about alternative procedures no matter how stupid or on average more dangerous, being 0% dangerous for the isolated situation where a crew gets cooked.

    A fueling accident is how the procedure will get rolled back, even if the rollback is on average on a system wide basis more dangerous.