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NASA denies SpaceX Crew Dragon propellant leak report, reveals unrelated heat shield defect

A view of a different SpaceX Crew Dragon heat shield after a recent reentry and recovery. (NASA)

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In a partial response to a report alleging evidence of several significant anomalies during a recent private astronaut launch that could affect a crew of NASA astronauts launched last month, the space agency has issued a statement denying those claims. However, the same statement simultaneously revealed that SpaceX recently discovered a different problem with a different Crew Dragon spacecraft component during ground testing.

On May 23rd, Space Explored published a report alleging that a SpaceX Crew Dragon spacecraft experienced major issues during Axiom-1, the company’s first all-private astronaut launch to the International Space Station (ISS). According to sourced info and a possible internal SpaceX memo, some of Dragon’s toxic propellant leaked during the 17-day flight, damaged or weakened parts of its heat shield, and “[caused] dangerously excessive wear upon reentry.” In general, the report appeared to be well-sourced and even alleged that NASA’s Engineering and Safety Center (NESC) had opened an investigation. Additionally, when approached for comment, neither NASA nor SpaceX were initially willing to speak on the record, which also meant that neither denied the accusations.

A day later, NASA provided an official statement to Space Explored explicitly denying that there has been any propellant leak, heat shield contamination, or excessive heat shield wear on any of “Dragon’s recent crew reentries.”

NASA also dismissed concerns about the reuse of a previously-flown Cargo Dragon 2 heat shield structure on Crew-4, which launched just two days after Axiom-1’s recovery and is scheduled to spend four to five more months in orbit. It also noted that the reuse of Dragon’s heat shield tiles – the structures that take the brunt of most reentry heating and are immersed in salt water after every mission – is extremely limited and has only been attempted on occasional Cargo Dragon missions.

Simultaneously, NASA revealed that “a new heat shield composite structure intended for flight on Crew-5 did not pass an acceptance test” at SpaceX’s Hawthorne, California Dragon factory. The unrelated test failure was blamed on a manufacturing defect and NASA betrayed no sign of serious concern in its statement, suggesting that the problem may be less serious than it sounds. In response, NASA says SpaceX will simply use a different heat shield composite structure for Crew-5, which is scheduled to launch no earlier than (NET) September 2022.

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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. 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 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. SpaceX has only demonstrated reuse of selected PICA (Phenolic-Impregnated Carbon Ablator) tiles, which is a lightweight material designed to withstand high temperatures, as part of the heat shield on cargo flights.

NASA and SpaceX are currently in the process of determining hardware allocation for the agency’s upcoming SpaceX Crew-5 mission, including the Dragon heat shield. SpaceX has a rigorous testing process to put every component and system through its paces to ensure safety and reliability. In early May, a new heat shield composite structure intended for flight on Crew-5 did not pass an acceptance test. The test did its job and found a manufacturing defect. NASA and SpaceX will use another heat shield for the flight that will undergo the same rigorous testing prior to flight.

Crew safety remains the top priority for both NASA and SpaceX and we continue to target September 2022 for launch of Crew-5.


NASA – May 24th, 2022

Some oddities do remain. While NASA’s explicit refutation should be taken as the definitive final word on the matter, it’s still very unusual that NASA and SpaceX refused or were unable to quickly and publicly deny the claims within a few hours of being asked. That could simply be a consequence of NASA and SpaceX’s poor internal and external communication or both parties’ love for withholding information from taxpayers about systems and technologies that those same taxpayers have paid for.

Axiom-1 was recovered without (reported) issue on April 25th. (Axiom Space)
Less than two weeks later, after greenlighting SpaceX’s Crew-4 NASA astronaut launch two days after Axiom-1’s recovery, NASA allowed SpaceX to return four Crew-3 astronauts to Earth with a third Crew Dragon. (SpaceX)

On the opposite hand, after Crew Dragon’s Demo-2 run-in with greater-than-expected heat shield wear in 2020, it’s almost impossible to imagine that NASA and SpaceX would have proceeded with Crew-4’s launch two days after Axiom-1’s recovery without confidently verifying that heat shield erosion was within normal bounds. SpaceX’s upgraded Phenolic-Impregnated Carbon Ablator (PICA-X) Dragon heat shield tiles are reportedly designed to erode [PDF] less than a centimeter of their circa-2017 ~7.5 cm (3 in) thickness after each reentry. Musk has gone even further, stating in 2012 that “[PICA-X] can potentially be used hundreds of times for Earth orbit re-entry with only minor degradation each time.” If true, it would be extremely difficult for even a brisk post-flight inspection of Axiom-1’s Dragon capsule to miss what Space Explored described as “dangerously excessive wear.”

In theory, during recovery, even a minute propellant leak should have also been immediately detected by SpaceX’s recovery team, as the very first part of the hands-on process involves a small team with gas masks and detectors approaching the floating capsule to ensure that it’s safe for others to approach. Crew Dragon’s liquid monomethylhydrazine (MMH) fuel and dinitrogen tetroxide (NTO) oxidizer are highly toxic in small quantities and MMH is a known carcinogen.

All told, news of a potential propellant leak and anomalous heat shield performance appears to have been a false alarm, although – coincidentally or not – a seemingly minor anomaly with an unflown Crew Dragon heat shield structure did occur earlier this month. Despite that anomaly, Crew-4 and Crew-5 are otherwise proceeding nominally and NASA appears to be content with Crew Dragon’s performance during several recent launches and recoveries.

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Eric Ralph is Teslarati's senior spaceflight reporter and has been covering the industry in some capacity for almost half a decade, largely spurred in 2016 by a trip to Mexico to watch Elon Musk reveal SpaceX's plans for Mars in person. Aside from spreading interest and excitement about spaceflight far and wide, his primary goal is to cover humanity's ongoing efforts to expand beyond Earth to the Moon, Mars, and elsewhere.

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Tesla begins validating Robotaxi in a new area, hinting at expansion

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Credit: Tesla

Tesla is validating Robotaxi in a new area, and as the company has continued to gain some additional permissions to begin testing in new states, it seems its Full Self-Driving-based ride-hailing project is moving toward a larger footprint.

Two Robotaxi units with LiDAR validation equipment were spotted in Gilbert, Arizona, recently, showing that Tesla is aiming to launch its ride-hailing service in the state soon:

Another unit was spotted in Tempe, Arizona:

These types of validation vehicles have been spotted in several areas ahead of their launch as a public ride-hailing service for passengers. Tesla first launched Robotaxi in Austin, Texas, back in late June, and since then, it has expanded to the Bay Area of California.

However, Tesla has continued to attempt to expand Robotaxi to other areas as well, including Nevada and Arizona. It has also been working toward approvals in other states based on job postings, as Tesla is hiring for Autopilot Vehicle Operators in New York and Florida, as well.

The expansion of the Robotaxi ride-hailing service has been an effort that Tesla has been spending a lot of time on over the past few months. CEO Elon Musk said the expansion aims to bring Robotaxi to at least half of the U.S. population by the end of the year, but there is still plenty of work to be done.

Tesla Robotaxi heads to a new major Texas city for the first time

Tesla did make its Robotaxi app public in recent months, allowing more members of the public to experience the suite for themselves, as long as they could get to Austin or the Bay Area.

In the coming months, it seems more apparent that Tesla will take a broader focus on expanding Robotaxi, especially with the fact that these validation vehicles are being spotted throughout different parts of the United States.

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Tesla mulls revamping $25k car, strange report claims

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Credit: Tine Rusc

Tesla is reportedly mulling the potential revamp of its $25,000 vehicle project, a strange report claims.

It seems unlikely, especially since Tesla launched two new, more affordable models last week with the Model 3 and Model Y Standard trims.

However, a report from European media outlet 36kr claims Tesla has started to advance two vehicle projects, internally codenamed E41 and D50, in China.

People familiar with the matter reportedly told the outlet that “some design and verification reports of the new projects are inherited from the current Model Y and Model 3.”

Tesla axed one of the Model Y’s best features in ‘Standard’ trims: here’s why

These new simplified models would be priced between $5,000 and $5,500 cheaper than what the new ‘Standard’ trims cost. The report also claims that these vehicles would be launched only if the new ‘Standard’ models “fall short of sales expectations.”

This report suggests that potentially more affordable models are being offered, but this seems unlikely, considering Tesla launched the two Standard models just last week, and the only truly affordable model it is working on will be the Cybercab.

However, there is potential for a car to launch that undercuts the newest configurations of the Model 3 and Model Y. As of now, it just seems as if it is something that is far-fetched.

When Tesla’s patent for the unboxed process was published just last month, it seemed more than obvious that the vehicle it would be used for was the Cybercab.

The language used in the patent itself was geared toward more streamlined and quality production and manufacturing, which Tesla must implement to meet the likely demand for the vehicle.

It will be easier to scale vehicles with the unboxed process, and the Cybercab has been routinely mentioned with the sub-$30,000 price tag, even by CEO Elon Musk.

He said during the Q3 2024 Earnings Call:

“I think having a regular 25K model is pointless. It would be silly. Like it would be completely at odds with what we believe…It’s fully considered cost per mile is what matters. And if you try to make a car that is essentially a hybrid, manual, or automatic car, it’s not going to be as good as a dedicated autonomous car. So, yes, Cybercab is just not going to have steering wheels and pedals.”

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SpaceX aces Starship’s 11th launch with success in every mission objective

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Credit: SpaceX

SpaceX aces its eleventh Starship test launch on Monday evening, marking the company’s second consecutive takeoff that crossed off each of the planned mission objectives.

It was also the final launch of the V2 Starship rocket. The twelfth test flight will feature the larger V3 Starship rocket, followed by V4, which will eventually make the first trip to Mars.

The launch was overwhelmingly successful. In its 12th test flight, SpaceX was able to achieve every major mission objective, including the second successful deployment of Starlink satellite simulators and the relight of a Raptor engine while in space. The latter achievement demonstrated “a critical capability for future deorbit burns,” the company said.

The ship officially launched at 6:23 p.m. local time in Starbase, Texas, with all 33 engines igniting and sending the Ship to space.

Stage separation occurred just over eight minutes later, and Super Heavy started its descent back to the Gulf of America, where it successfully splashed down. The first part of the launch was complete.

Starlink simulators were deployed about twenty-one minutes after launch, as the Pez dispenser sent the faux-satellites out to space without any issue:

Perhaps the most anticipated part of the launch was with Starship’s banking maneuver and subsequent splashdown in the Indian Ocean.

Prior to Starship 11’s launch and successful re-entry and splashdown, SpaceX had lost a few vehicles during this portion of the previous flights.

However, the company had made tremendous improvements and has now aced two consecutive launches. On Monday, its approach and splashdown were both overwhelmingly successful:

The re-entry phase of this particular Starship launch aimed to gather data on the performance of the heatshield, SpaceX said. The heatshield was intentionally stressed to its limits to determine how much it could withstand without failing.

SpaceX will now turn its focus to the next vehicles, including V3, which is larger, more capable, and will help the company gather even more information about its launches into space:

CEO Elon Musk has said the third-generation Starship rocket will be built and tested by the end of the year.

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