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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) by takyon on Monday August 13 2018, @04:25PM (18 children)

    by takyon (881) <reversethis-{gro ... s} {ta} {noykat}> on Monday August 13 2018, @04:25PM (#721026) Journal

    Basically, the astronauts will be going into a heavily shielded capsule that can escape and survive an explosion (Crew Dragon is designed to re-enter the atmosphere from orbit), before any propellant is loaded into the rocket. vs. boarding a fueled rocket with ground crew present, all of whom would die if there was an explosion.

    The payload destroyed by the September 2016 accident didn't have the same level of protection.

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    • (Score: 2, Disagree) by ikanreed on Monday August 13 2018, @04:40PM (7 children)

      by ikanreed (3164) Subscriber Badge on Monday August 13 2018, @04:40PM (#721035) Journal

      I think you're wildly underestimating how devastating a rocket explosion is, and moderately overestimating how bad reentry is.

      I mean, I wouldn't be able to design a craft that could survive re-entry, but the core problem is solved with ceramics with very high heat tolerance and good aerodynamics.

      Explosions introduce not just heat, but allomorphic kinetic energy, and shrapnel. I highly doubt a M88 ARV would survive a rocket explosion, and that's built with heavy armor designed for explosions, not ultra-light spacecraft construction.

      I mean, maybe I've just come to decide Musk is kind of an asshole, and am not giving credit for what might work, and someone has shown that a Dragon Crew Module would survive the explosion, but your conjecture here sounds pretty unlikely to me.

      • (Score: 3, Informative) by takyon on Monday August 13 2018, @05:05PM (3 children)

        by takyon (881) <reversethis-{gro ... s} {ta} {noykat}> on Monday August 13 2018, @05:05PM (#721044) Journal

        Well, if you won't believe me, take it from Dr.Koenigsmann over here [digitaljournal.com]:

        NASA plans to address concerns over the "load-and-go" method as well as other safety concerns at the second quarterly meeting of the Aerospace Safety Advisory Panel, scheduled for May 17, 2018. The meeting will give priority "to those programs that involve the safety of human flight," and will offer updates on the Commercial Crew Program, according to a notice from NASA [federalregister.gov].

        But in a Congressional hearing in January this year, Dr. Hans Koenigsmann, the vice president of build and flight reliability at SpaceX spoke on the fueling processes SpaceX uses and said that SpaceX actually believes that the "load-and-go" fuelling process is a safer way to fuel.

        “What we tried to do here is we tried to minimize the time we expose personnel, not just astronauts, but also crew to the hazard of fueling,” Dr. Koenigsmann said during the panel [house.gov].

        “In this particular case, our procedure is actually that we put the astronauts, we strap them in, we make sure they’re comfortable, and then the ground crew retreats and we arm the pad abort system that we’ve already tested. Then we start fueling the main propellants basically within what amounts to half an hour or something like that. So it’s a relatively quick procedure and we believe that this exposure time is the shortest possible and therefore the safest approach,” he told the panel.

        It was also noted that SpaceX's Dragon spacecraft is outfitted with a nearly instantaneous crew abort system. The safety gear has small engines that jettison the crew capsule away from the rocket in the event of an emergency. The video accompanying this story shows how the Dragon is jettisoned and how it lands.

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        • (Score: 4, Insightful) by ikanreed on Monday August 13 2018, @05:53PM (2 children)

          by ikanreed (3164) Subscriber Badge on Monday August 13 2018, @05:53PM (#721066) Journal

          What do you mean by this having expert analysis that directly undercuts my amateur observation? Surely I cannot be wrong about this?

          (I'm totally wrong)

          • (Score: 0) by Anonymous Coward on Monday August 13 2018, @06:13PM

            by Anonymous Coward on Monday August 13 2018, @06:13PM (#721075)

            This is how you do it buzzy my boy! The joke would complement your style, but you need the part in parenthesis.

          • (Score: 2) by bob_super on Monday August 13 2018, @06:55PM

            by bob_super (1357) on Monday August 13 2018, @06:55PM (#721099)

            Considering that NASA was initially against the idea, then got convinced that it's safe by SpaceX, there's a good chance that it has been reviewed by a lot of experts who had a significant incentive to not put their name on the approval of something that could turn into horrible PR.

            The NASA version of Titanic would have hit the iceberg straight on (better in hindsight), and kept pushing the iceberg all the way to NY, before getting retrofitted five years later with an oversized rudder. SpaceX risks a physics Nobel prize for managing to turn that ship.

      • (Score: 2) by takyon on Monday August 13 2018, @05:10PM

        by takyon (881) <reversethis-{gro ... s} {ta} {noykat}> on Monday August 13 2018, @05:10PM (#721048) Journal

        http://www.spaceflightinsider.com/organizations/space-exploration-technologies/nasa-may-be-warming-to-the-idea-of-spacexs-load-and-go-fueling-procedure/ [spaceflightinsider.com]

        Others, however, feel the risk is acceptable. SpaceX’s CEO Elon Musk expressed his confidence in the design. When asked, on Twitter, if the capsule would have survived had the escape system activated, Musk replied [twitter.com]: “yes [sic]. This seems instant from a human perspective, but it [is] really a fast fire, not an explosion. Dragon would have been fine.”

        Though SpaceX has yet to conduct its in-flight abort test, it successfully completed [spaceflightinsider.com] a pad abort test on May 6, 2015. When pundits overlaid [rebrn.com] the footage of the abort test on the Amos-6 incident, it does appear that the capsule, and its crew, would have been whisked to safety.

        Though the fueling process and the COPV failure are two separate issues, they are often conflated. However, it would appear that ASAP members have made peace with the former, though the latter is still an area of concern. To allay that concern, Musk says SpaceX has re-engineered the problematic vessels to make them safer.

        “This is by far the most advanced pressure vessel ever developed by humanity. It’s nuts. And I’ve personally gone over the test design – I’ve lost count how many times. But the top engineering minds at SpaceX have agonized over this. We’ve tested the living daylights out of it. We’ve been in deep, deep discussions with NASA about this. And I think we’re in a good situation,” stated Musk in a call [cnbc.com] held with the media.

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      • (Score: 1) by Sulla on Monday August 13 2018, @05:18PM

        by Sulla (5173) on Monday August 13 2018, @05:18PM (#721052) Journal

        Here is a pad explosion of the Falcon 9.
        https://www.youtube.com/watch?v=_BgJEXQkjNQ [youtube.com]

        1:11 - Explosion begins
        1:20 - Payload falls from top of rocket
        1:23 - You can see the payload, based on the light around it there does not look to be any punctures

        So if you have the escape system primed to go and the computers sense a breach between 1:11 and 1:20 the DCM should be able to survive. Now.. I don't know how long it takes for those DCM engines to kick in.

        From wikipedia

        On 6 May 2015, SpaceX completed a pad abort test for the Dragon 2.[76][77][78][79] During this test, the Dragon used its abort engines to launch away from a test stand at Launch Complex 40.[76][77][79] It traveled to an altitude of 1,187 meters (3,894 ft),[80] separated from its trunk, deployed its drogue parachutes and then the main parachutes.[77][79] It splashed down into the ocean and was recovered.[77][79] The vehicle was planned to reach an altitude of 1,500 meters (5,000 ft) but one of the engines underperformed due to an abnormal fuel mixture ratio.[77][78] The Dragon flown is planned to be refurbished for the in-flight abort test.[78][79]

        In a planned in-flight abort test, Dragon will use its launch abort engines to escape from a modified Falcon 9 that is already in flight.[81][82] The launch is planned to occur from SLC-4E.[79] This test will occur at the point of worst-case dynamic loads, which is also when Dragon has the smallest performance margin for separation from its launch vehicle.[81] The Falcon 9 planned to be used will only have three engines on the first stage and will have no second stage.[79]

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      • (Score: 1) by khallow on Tuesday August 14 2018, @09:43AM

        by khallow (3766) Subscriber Badge on Tuesday August 14 2018, @09:43AM (#721301) Journal

        I think you're wildly underestimating how devastating a rocket explosion is, and moderately overestimating how bad reentry is.

        Who is doing that? Keep in mind that the whole point of the system is to not be there when the rocket explosion happens. The ground crew isn't present because all that crew loading happened before fueling nor is the crew on the capsule - because the launch abort system just moved them a considerable distance away from the exploding rocket and just like in orbit, they are designed to keep flying debris out of crew members.

        As to reentry? It's a solved problem. SpaceX seems pretty good at solving out problems even when they aren't already solved.

    • (Score: 2) by DannyB on Monday August 13 2018, @05:25PM (4 children)

      by DannyB (5839) Subscriber Badge on Monday August 13 2018, @05:25PM (#721056) Journal

      NASA's procedure is to have crew and ground crew crawling an already fueled rocket.

      Does that increase the chants of a spark which could ignite any fuel vapor that might be present?

      --
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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.
        • (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.

    • (Score: 2) by legont on Tuesday August 14 2018, @12:58AM (4 children)

      by legont (4179) on Tuesday August 14 2018, @12:58AM (#721194)

      Can we have Mask the pedophile standing next to the crew capsule during the fill up? just in case, you know.

      --
      "Wealth is the relentless enemy of understanding" - John Kenneth Galbraith.
      • (Score: 2) by takyon on Tuesday August 14 2018, @01:40AM (3 children)

        by takyon (881) <reversethis-{gro ... s} {ta} {noykat}> on Tuesday August 14 2018, @01:40AM (#721202) Journal

        He's a pedo hunter, not a pedophile. Like duh.

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        • (Score: 2) by legont on Tuesday August 14 2018, @04:08AM (2 children)

          by legont (4179) on Tuesday August 14 2018, @04:08AM (#721232)

          Usually people are hunting devils within themselves, but finding them in others.

          Anyway, calling somebody pedo as a revenge for being called an idiot tells a lot about the person; especially given our current environment and their relative standing. Mask is a total ass and he can have his rocket where his submarine already is.

          --
          "Wealth is the relentless enemy of understanding" - John Kenneth Galbraith.
          • (Score: 2) by takyon on Tuesday August 14 2018, @04:38AM

            by takyon (881) <reversethis-{gro ... s} {ta} {noykat}> on Tuesday August 14 2018, @04:38AM (#721242) Journal

            Usually people are hunting devils within themselves, but finding them in others.

            Sounds like a view that is entirely anecdotal and rooted in media sensationalism. There's no juicier story than a Republican gay-bashing politician found to have a gay lover. Or the Atkins diet guy fattening up, having a history of heart failure, and dying from falling down on the street. Rather than pedophilia, Musk is guilty of perpetuating a stereotype of Thailand, although not an entirely unfounded one [wikipedia.org].

            Anyway, calling somebody pedo as a revenge for being called an idiot tells a lot about the person; especially given our current environment and their relative standing. Mask is a total ass and he can have his rocket where his submarine already is.

            He is allowed to defend himself on social media, even given his "relative standing". But facts aside, as long as Musk gives us BFR, he could shoot a guy in the middle of Bel Air and I wouldn't care. Your disdain is worthless and beneath the Gaze of the Musky One.

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          • (Score: 1) by khallow on Tuesday August 14 2018, @09:53AM

            by khallow (3766) Subscriber Badge on Tuesday August 14 2018, @09:53AM (#721305) Journal

            Usually people are hunting devils within themselves, but finding them in others.

            So all these critics of Musk are crypto-rocketmen with that secret lust for the cryogenically-fueled shaft? Ye gods! The internet has fallen further than I could possibly imagine!

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