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Did SpaceX’s Endeavour capsule have issues with its heat shield during its most recent return to Earth?

According to a May 23rd Space Explored article based on anonymous sources, the heat shield on SpaceX’s Endeavour capsule experienced “dangerously excessive wear upon reentry” because of a propellant leak.

Hypergolic propellant made its way into the Crew Dragon Endeavour’s heat shield, according to sources at SpaceX and NASA who spoke with Space Explored. This hypergolic propellant is used by the Crew Dragon in its Draco engines – hypergolic means that the two parts spontaneously combust upon contact. It is believed that this hypergolic propellant impacted the integrity of the heatshield, causing dangerously excessive wear upon reentry.

NASA however has now bluntly denied these claims:

“The data associated with Dragon’s recent crew reentries was normal — the system performed as designed without dispute. There has not been a hypergol leak during the return of a crewed Dragon mission nor any contamination with the heat shield causing excessive wear,” the NASA statement reads, in part.

“SpaceX and NASA perform a full engineering review of the heat shield’s thermal protection system following each return, including prior to the launch of the Crew-4 mission currently at the International Space Station,” the NASA statement continues. “The heat shield composite structure (structure below the tile) was re-flown per normal planning and refurbishment processes. The thermal protection system on the primary heat shield for Crew-4 was new, as it has been for all human spaceflight missions.”

Such a flat out denial by NASA strongly suggests that the anonymous sources relied on by Space Explored are not reliable, and got their facts wrong. While NASA will often try to hide or spin any issues to make them seem less worrisome, it has almost never denied the existence of a serious problem, when it was revealed that such a problem had occurred.

I know to say this sounds paranoid, but this story also suggests this claim might be part of the growing effort within the federal bureaucracy and the press to attack SpaceX, because of its new irrational hostility to Elon Musk because he supports achievement and free speech.

At the same time, SpaceX has recently had to discard and replace a Dragon heat shield planned for a future mission because of discovered “manufacturing defect” during normal preflight testing. This confirmed story, combined with the unconfirmed and questionable story above, suggests SpaceX needs to take a closer look at the Dragon heat shield design.

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On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.

The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.

The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.

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  • George C.

    Subjecting the NASA statement to first order predicate calculus, it is still possible that there has been a leak, just not during a return. Also possible that there has been contamination of heat shield causing wear, just not excessive.

    And all this is normal. Given all the heat stress and vibration I can’t see how all seals could be perfect all the time. Just keep an eye on those O rings

  • Alton

    Always…by Any Means Necessary…
    Like disqualifying the top three Republicans from the Ballot in the Michagan Governor’s Race Primary.

    As three Republicans were also stricken from the Tennessee Ballot. One a Trump Pick.(Congressional)

    A Court Case has been filed here locally to have the current setting Congressman Removed from the Ballot in the fall for being a Jan 6th insurrectionist, interesting the So-Called Republican Woman in the Primary who filed the case says she has spent $350,000 running in the race. Being Active in Politics I had never heard of her before, and the Warren Buffett owned largest newspaper here in South West Virginia has no articles in it’s database until she filled the lawsuit………

    Another Democracy Docket Project.

    From Wiki via Google Turd:
    Democracy Docket is a Democratic Party voting advocacy group. The group was founded in 2020 by lawyer Marc Elias with funding from the Hopewell Fund and Priorities USA Action.
    Founder: Marc Elias
    Founded: 2020

  • Phill O

    Just because you are paranoid, does not mean people are not out to get you!

  • Rockribbed1

    Lex Luthor trying to hurt spacex.

  • Col Beausabre

    “Paranoia strikes deep
    Into your life it will creep
    It starts when you’re always afraid
    Step out of line, the men come and take you away”

    – Buffalo Springfield “For What It’s Worth”

    As a Child of the Sixties (c), I can’t help but bring this up


  • Col Beausabre

    What the heck, from the same period, The Elon Musk Theme Song – “Hey, Mr. Spaceman” by the Byrds

    After the first time I played it, my fraternity roommate looked at me and said, “Is that really about what I think it is about?”

  • Jeff Wright

    Space Explored broke the story of the collapsed core of Booster7.

    Elon has a mole.

  • David M. Cook

    Heat shield design has been a well-known science, not art, since the late 1960‘s! It should be a no-brainer to make something that will easily handle Mach 50. It was already done for the Galileo probe at Jupiter, which survived an entry speed of 29 miles/second. It was less than 6“ thick! This should be an easy thing to get right.

  • David Eastman

    David M. Cook – A one use heat shield for a probe, where you design for a very hard high-g re-entry with a high peak heat but it’s over fast, and then you simply eject the shield before it radiates any of that heat back into the craft, is a very different design than something that has to face a lower peak temperature, but will see peak heating for a period of several minutes, and then can’t be either discarded, or let that heat radiate into the craft. And also, there is the matter of expense. Unobtanium materials for a billion dollar once in a century probe that isn’t very large are not viable for something that needs to be large enough to protect a craft holding multiple people, and a mission that you want to repeat many times a year. In short, no, it’s not an easy thing to get right, especially when there are lots of different definitions of “right”.

  • Chris

    So as Mr Z often relays about SpaceX, they will look at what has occurred and determine if something is wrong. Then they will correct it if necessary AND make it cheaper to build.

  • Col Beausabre

    More Muskhate

    “The world’s richest man is no stranger to polling his users on Twitter Inc (NYSE: TWTR) to prove his points or opinions. A poll was put forth on Twitter by another user to try and show that Musk’s polls may not be accurate, but backfired.

    “Here are the details. What Happened: Tesla Inc (NASDAQ: TSLA) CEO Elon Musk, who is pursuing an
    acquisition of Twitter, recently polled users to see who people trust less, billionaires or politicians. The poll showed that 75.7% of Musk’s followers trust politicians less than billionaires.

    In response to the poll, Occupy Democrats writer David Weissman made his own poll in an attempt to show lack of support for Musk

    “Let’s prove how phony the right’s ridiculous polls are by doing one of our own. Who do you trust more?” Weissman asked on Twitter. The two possible selections were Musk and AOC, referring to Alexandria Ocasio-Cortez.

    Musk won the poll with 81.2% of the vote, showing that he is far more trusted than Ocasio-Cortez, the U.S. Representative serving the state of New York.”

    1) “Let’s prove how phony the right’s ridiculous polls are” A nice neutral pollster not trying to influence the outcome. Was he born this stupid or did he only achieve it through years of hard work and study?

    2) Proof of the absolute bubble the Left lives in

  • Col Beausabre: Forgive me, but I like your term “Muskhate” so much I am now going to use it as the opening word on similar examples of the new effort to destroy Musk.

  • Ray Van Dune

    Asking me who I trust more, Musk or AOC, is like asking whose judgement I trust more, that of an accomplished adult or a petulant child’s.

  • Edward

    Parsing the press release is a tactic to find things that are not there. Strangely, some people ignore that the original article is wrong in its report, but those people attempt to keep it as right as possible. Maybe there was a leak bu tit didn’t cause excessive damage. Maybe the leak wasn’t during reentry. But nowhere could it be possible that there was no leak at all.

    “Muskhate” may be the correct term.

    Ray Van Dune began: “Asking me who I trust more, Musk or AOC, is like asking whose judgement I trust more, …

    I have a different ending: that of an steely eyed missile man or a politician’s.

    How do you know when a politician is lying? Her lips are moving.

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