May 25, 2018
Image credit: Nathan Koga / SpaceFlight Insider
Although NASA had previously been skeptical about the security of SpaceX proposed workflow of fueling the Falcon 9 launch vehicle while the astronauts were on board, members of a key security panel at the agency may now be warming up with the idea.
During a meeting on May 17, 2018, members of the Aerospace Security Advisory Panel ( ASAP ) appear to have softened their stance on the risks badociated with the SpaceX loading procedure – colloquially called "loading" and carry "- and has indicated that the process can be compatible with the flight with crew.
"My sense is that, baduming that there are adequate and verifiable controls identified and implemented for causes of credible risk, and those that could potentially result in an emergency situation … it seems that the option to load and carry is a viable option for the program, "said panel member Capt. Brent Jett Jr. (Ret.), As reported in article by LA Times.
Historically, NASA has not allowed astronauts to board the spacecraft until the refueling process completes. However, with SpaceX preferring to charge sub-cooled propellant – liquid oxygen (LOX) and kerosene RP-1 – to increase the density of the oxidant and fuel, the sourcing process would occur much later in the countdown, which means that the astronauts They would address it long before the fuel supply is completed.
Critics of the loading and transit process point to the incident of September 1, 2016, in which a Falcon 9 vehicle and its AMOS-6 payload of $ 185 million were lost when one of the three wrapped pressure composite containers (COPV) in the LOX tank of the second stage failed after a detonation of solidified oxygen in the coating.
The cancellation test of the pill was carried out before the incident with the pill Amos-6. Would the escape system have protected the crew and the craft? Image credit: Mike Howard / SpaceFlight Insider
In fact, retired NASA astronaut Thomas Stafford, veteran of four space flights, including Apollo 10, noted his concern in a letter to William Gerstenmaier, Associate Administrator of NASA for Exploration and Human Operations. months before of the incident. Stafford, in his role as a member of the Advisory Committee of the NASA International Space Station, wrote to Gerstenmaier:
" There is a unanimous and strong feeling on the part of the committee that programs the The crew being on board the Dragon spacecraft before loading the oxidant into the rocket is contrary to the reinforcement safety criteria that have been in place for more than 50 years, both in this country and internationally. The crew or any other personnel have been allowed near or near the booster during fuel loading, only after the booster has been fully powered and stabilized, the few essential people who are allowed to be near it. ] "- Thomas P. Stafford
Others, however, consider the risk acceptable. SpaceX CEO Elon Musk expressed his confidence in the design. When asked, on Twitter, if the capsule would have survived if the escape system had been activated, Musk responded : "yes [sic]." This seems instantaneous from a human perspective But it really is a fast fire, not an explosion, Dragon would have been fine. "
Although SpaceX has not yet carried out its abortion flight test, completed a pads cancellation test on May 6, 2015. When the experts overlapped  the images of the abortion test in incident Amos-6, it seems that the capsule and its crew would have been taken to a safe place.
Although the fuel loading process and the COPV failure are two separate issues, they are often combined. However, it seems that ASAP members have made peace with the former, although the latter remains an area of concern. To dispel that concern, Musk says that SpaceX has redesigned the problem boats to make them safer.
"This is by far the most advanced pressure vessel ever developed by mankind, it's crazy and I personally reviewed the design of the test: I've lost count how many times, but the superior engineering minds at SpaceX have agonized over We have tested the living daylight, we have been in deep and deep conversations with NASA about this, and I think we are in a good situation, "Musk said in a call held with the media.
That said, Musk seems to be ready to work with NASA if the agency still feels the risk feeding is too high.
"So I really do not think this represents a safety issue for the astronauts, but if, for whatever reason, that NASA felt different, we can adjust our operating procedures to load propellant before the astronauts board," he concluded. Musk.
The commercial crew of NASA is expected to make a final decision on the loading and shipping sequence in the near future.
The SpaceX space suit with the Crew Dragon capsule. Photo credit: Elon Musk / SpaceX
Tagged: Dragon Lead Stories Load and Go SpaceX commercial crew program
Curt Godwin has been a fan of exploration space for as long as he can remember, keeping his eyes on the sky from an early age. Initially with a specialization in Nuclear Engineering, Curt then decided that computers would be a more interesting and safer career field. He has worked in educational technology for more than 20 years, and has been published in industry and peer journals, and is a respected authority on wireless network engineering. Throughout this period of his life, he maintained his love for space and has written about his experiences in a variety of NASA events, both on his personal blog and as an independent representative of the media.