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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.

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 Cybercab uses a unique strategy for picking up the right rider

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Credit: ARTSIMAGE | X

Tesla Cybercab is using a unique strategy for picking up the correct rider, which is a crucial part of ride-hailing to ensure people end up in the right place and are charged the correct price.

Cybercab will utilize an RGB strip in its front light bar that will illuminate in a variety of different colors to mark itself.

This identifying mark will also appear in the Robotaxi app, giving riders in the same location a notable distinction in an effort to avoid any confusion regarding who should get in each vehicle.

Other ride-hailing services use similar strategies: Lyft and Uber rides are recognizable through driver identity, vehicle type and color, as well as license plate. Waymo will display the rider’s initials on top of the vehicle, letting them know that the specific vehicle for them has arrived.

Tesla’s strategy is unique and interesting, but there are some flaws. Cybercab’s main purpose is aimed toward being an autonomous ride for all, including those who have disabilities like being blind or even color blind.

Tesla will likely have something in the pipeline for those who cannot see colors or have limited vision. There will definitely be multiple ways to identify which vehicle is the one that “you” specifically ordered.

Cybercab is set to start giving public rides next Thursday, September 3, in Austin, as it announced a dedicated event last week and invited many members of the Tesla community.

Tesla will launch Cybercab on September 3

Additionally, members of the public will be invited as well. Tesla has been offering employee rides in Cybercab for nearly two months.

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Tesla ends in-house wrap service that always seemed like a short-term program

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Credit: Tesla

Tesla has said goodbye to one customization option for its vehicles: the wrap service it launched several years ago.

After launching an in-house wrap service in August 2020 for the first time in China. In the U.S., it launched in October 2023. Tesla continued to expand the program and adjust it with better pricing and fewer options for the Cybertruck.

By December 2023, it was giving owners of the Model 3, Model Y, and the Cybertruck the opportunity to give their vehicle a fresh look with a vinyl wrap.

Tesla revamps in-house vinyl wrap service with better pricing

It was only available in five locations: Costa Mesa, Oceanside, Santa Clara, West Covina, all in California, and Seattle, Washington.

However, Tesla made some big adjustments to its shop, and the wrap service is officially gone:

Wraps are very popular across the Tesla lineup, especially since the company offers relatively few colors. Many choose to wrap their Teslas with interesting colors, patterns, or even finishes, turning their cars from glossy to satin or matte.

However, Tesla’s wrap service was so limited geographically that it never really had a chance to get off the ground or compete with local shops. Every area in the United States is now overflowing with detailing shops, mobile detailers, and other automotive specialists, many of whom perform wrap services.

Tesla’s service was confined to the Pacific time zone and only spanned across two states. It was never going to be something Tesla was a major competitor in, nor was it going to disrupt the wrapping industry. Now that the program has ended, it seems pretty ideal to believe it was always going to be a short-term thing.

Along with the wrap service, Tesla removed several other products, but nothing too crazy. The Model 3 Door Pocket and Cupholder Liners, the Model S 19″ Magnetite Wheel and Winter Tire Package, Model X/Y Ski/Snowboard Carrier for Hitch Rack, Tesla’s Electric Summer Party Tee, and the Electric Summer Tee were the other items the company totally eliminated from its online shop.

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Tesla Robotaxi fleet gets a brain upgrade ahead of Cybercab launch event

Tesla’s Robotaxi service now runs longer hours nationwide as its unsupervised fleet quietly grows larger.

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Tesla’s Robotaxi service just got easier to catch, with the company’s official Robotaxi account noting that rides are now available from 6 a.m. to 10 p.m., seven days a week, across its operating footprint. The account also said its unsupervised fleet is “a lot bigger” than before, though without specifics. The bigger change is what Tesla says upgraded intelligence in vehicle distribution and routing is what’s actually cutting wait times, not a new Full Self-Driving version.

While Tesla did not name the team behind the upgrade, the language points to its AI and fleet software group rather than the driving stack itself. Vehicle distribution and routing in Robotaxi has functioned mostly as a dispatch problem with the software deciding which idle car goes to which rider, and how far it has to travel to get there. “Upgraded intelligence” suggests a smarter version of that dispatch logic, likely using demand forecasting to position idle cars near where riders are about to request them rather than reacting once a request comes in. Tesla’s AI division has built similar prediction systems for other parts of the business, including the neural networks that power FSD itself, so applying that same approach to fleet logistics would be a natural extension rather than a new discipline for the team.

Tesla is also about a week away from a separate robotaxi milestone. The company plans to launch Cybercab, its purpose built two seat robotaxi with no steering wheel or pedals, in Austin on September 3. Cybercab has been giving employees rides on public and private roads for weeks, and the September event is expected to fold those vehicles into the existing Robotaxi fleet within days of the launch.


Austin previously ran Robotaxi from 6 a.m. to 2 a.m. as of last September, a schedule set before the service expanded into Dallas, Houston, Miami, Tampa, Orlando and the Bay Area. Wednesday’s post did not specify whether that extended overnight window still applies in Austin specifically or whether 6 a.m. to 10 p.m. is now the standard across every market. Tesla’s post, visible on its official Robotaxi account, framed the change simply as fewer riders waiting around for a car.

Whether the wider hours hold once Cybercab enters the fleet next week is the next thing worth watching. Tesla has tended to expand Robotaxi in increments, first geofence, then hours, then fleet size, and each step so far has arrived without much advance notice.

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