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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

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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.

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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How Tesla’s Roadster fan system and thrusters are built to dominate the corners

Tesla’s Roadster uses fans, active wings and cold gas thrusters to create grip at any speed.

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The Roadster’s rear wing, one of the aerodynamic elements Tesla pairs with a fan-based downforce system. (Image: Tesla)
The Roadster’s rear wing, one of the aerodynamic elements Tesla pairs with a fan-based downforce system. (Image: Tesla)

Tesla’s new Roadster is best known for flipping through the air in Texas, but the technology that matters most for a race track is the stuff that keeps it on the ground. Tesla’s Roadster page describes a multi-mode fan and ground sealing system that acts as a downforce generator, pulling air out from beneath the car. Tesla says it provides enough suction to hold the vehicle upside down, even when stationary.

That is the key difference from the wings and diffusers on a normal supercar. Conventional aero only makes downforce when the car is moving, and it grows with speed, so a car has the least grip in the slow corners and under hard braking. A fan system makes downforce at any speed. Tesla’s patent, which we covered last year, describes fans and deployable skirts that create sealed or partially sealed regions under the car, with the fans extracting air to lower the pressure and increase grip and stability.


Tesla pairs that with active wings, a next generation steer by wire system and a Track Mode that lowers the car and changes the suspension, with high downforce and low drag settings for the circuit. To keep weight down, Tesla points to magnesium, titanium and carbon fiber, manual controls and a fixed seat position, which it says lets the car respond to driver inputs almost instantly.

Tesla Roadster: Three configs, one can fly, 0-60 in 0.8 seconds

The cold gas thrusters are the other half. On the Thrust version they sit at the rear and Tesla says they take the car from 0 to 60 mph in under 0.9 seconds, while the Rocket version adds perimeter thrusters for forward, upward and lateral rotational movement. Tesla says the all electric actuators make micro adjustments within a fraction of a second.


Musk has been talking about records for years. In June 2019 he said, “We’re going to do things with the new Roadster that are kind of unfair to other cars.” That September, when a follower asked whether the Roadster would beat the Nürburgring production car record, he replied with one word, “Absolutely,” as we reported at the time. In February 2024 he said Tesla had “radically increased the design goals” for the car and that its sub one second 0 to 60 time would be “the least interesting part.”

There are caveats. Tesla has not published a lap time or a verified cornering figure, so the record talk is still a promise rather than a result. Tesla also says the car is not approved for public road use, and the thruster features are limited to the Rocket trim, which is invite only. Fan cars have also been banned or withdrawn before, and getting a sealed underbody to work on a rough public road is a harder problem than on a smooth track. The first real test will be an official lap at a circuit.

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Tesla Roadster: Three configs, one can fly, 0-60 in 0.8 seconds

Tesla’s Roadster comes in Performance, Thrust and Rocket versions, with a claimed 0-60 under 0.59 seconds.

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Elon Musk addresses the crowd next to the new Tesla Roadster, which Tesla offers in Performance, Thrust and Rocket versions. (Image: Tesla/X)

Tesla finally showed the next generation Roadster on Thursday night, and the demo had more in common with a SpaceX test than a track lap. At an event outside Waco, Texas, near SpaceX’s McGregor site, the car used a mix of fans and cold gas thrusters to drive up a curved ramp until it was upside down, then flew off, flipped and landed on the pavement. “Well, it worked,” Elon Musk said. “Flying cars are real.”

The Roadster also hovered itself over a Cybercab, Cybertruck, Tesla Semi, Model Y and Model 3 while moving, and that Tesla showed it going 0 to 60 mph in one second. Musk said “this will be the actual car that’s on the roads” and that it “literally is just going to puff itself up” to perform the maneuvers whenever an owner wants. He called the result a collaboration between Tesla and SpaceX engineers that is “better than any James Bond car,” with Franz von Holzhausen and Lars Moravy on site.

Tesla published new mind-blowing stats for the car that replace the previous targets. The Performance version is road ready and seats two, with active aerodynamics and a multi-mode suction system, and Tesla lists 0 to 60 mph in under 1.6 seconds. The Thrust version is race ready, also seats two, and adds rear-mounted cold gas thrusters for a 0 to 60 time of under 0.9 seconds. The Rocket version is described as air ready, seats one, and uses perimeter-mounted thrusters for forward and upward acceleration plus lateral rotational movement.

Configuration Seats 0 to 60 mph
Performance 2 under 1.6 s
Thrust 2 under 0.9 s
Rocket 1 under 0.59 s

Tesla’s own description: “So…yes, it can fly.” It lists a 0 to 60 time of under 0.59 seconds for Rocket, a top speed of up to more than 230 mph, and range of more than 300 miles. Tesla has not yet given pricing in the information we have seen, but has reopened $50,000 reservations in the newly updated Tesla Roadster configurator. Production is planned for Giga Texas in 2027 or 2028, and Musk has said it would follow the demo by 12 to 18 months.

Tesla’s Roadster page adds more on how the car works. A multi-mode fan and ground sealing system pulls air from under the car, producing enough suction to hold it upside down even when stationary. Active wings, steer-by-wire with a yoke, and a Track Mode that lowers the car round out the driving setup. The cold gas thrusters use all-electric actuators for micro adjustments to stabilize the car in flight. Tesla says it cut weight with magnesium, titanium and carbon fiber, manual controls and a fixed seat position, and the exterior has hidden headlights, a full-length taillight and Ano White paint inspired by aerospace coatings. Inside are an Ultrawhite interior with gray microsuede, a center touchscreen and two smaller forward displays, and gold tinted glass modeled on spacesuit visors. Availability is tiered: Performance is by reservation, Thrust is a limited release, and Rocket is invite only. Tesla notes the car is not approved for public road use, and that Rocket is not available in all regions.

Tesla Roadster Highlights

  • Aero and suction: a multi-mode fan and ground sealing system pulls air from under the car and can hold it upside down even when stationary. There are also active wings and a Track Mode that lowers the car.
  • Controls and thrusters: steer-by-wire with a yoke. The cold gas thrusters use all-electric actuators for micro adjustments that stabilize the car in flight.
  • Weight: magnesium, titanium and carbon fiber, manual controls and a fixed seat position.
  • Design: hidden headlights, a full-length taillight, Ano White paint inspired by aerospace coatings, and gold tinted glass modeled on spacesuit visors.
  • Interior: an Ultrawhite interior with gray microsuede, a center touchscreen and two smaller forward displays.
  • Availability: Performance is by reservation, Thrust is a limited release, and Rocket is invite only.
  • Road use: Tesla notes the car is not approved for public road use, and that Rocket isn’t available in all regions.

Musk has described the Roadster as “the best of the last of the human-driven cars,” and he has been open that it is a halo product. He said he is “not sure it moves the needle massively from a revenue standpoint,” and has warned that anyone whose top priority is safety should not buy it. Tesla reports third quarter earnings on October 21.

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Amazon shuts out Elon Musk’s Grok Bot so he may just build his own rival store

Musk promises SpaceX will cover Grok Bot purchase errors, tells users to shop beyond Amazon.

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Concept rendering showing a silhouette of Elon Musk, arms folded, overlooking a sprawling modern Amazon warehouse via Grok
Concept rendering showing a silhouette of Elon Musk, arms folded, overlooking a sprawling modern Amazon warehouse via Grok

Elon Musk said SpaceX will reimburse users if Grok Bot botches a purchase or leaks their card details. A few hours later he was telling users to take their shopping elsewhere after Amazon shut the agent out.

The first post was a reply to an X user who said Grok Bot booked him a flight after he sent a photo of his credit card. “This works well,” Musk wrote. “If Grok @Bot makes a mistake with a purchase or leaks your card (never happened yet), SpaceX will make you whole,” said Musk.

The second came after another user posted the error his Grok Bot hit on Amazon: “Continued access by an unauthorized AI agent violates Amazon’s Conditions of Use, to which our customers have agreed.” The user said his bots can no longer order from the site. Musk answered, “Just ask Grok @Bot to buy what you want someplace else and get a better deal. There are far more purchasing websites than just Amazon!” He later added, “Maybe we should start a competitor to Amazon,” a possible hint at an X shopping service.

The Amazon block did not start Thursday. A reply to Musk on October 10 said Amazon was blocking the bot, and Musk responded that Grok would find another way, then showed an order it placed on Lego’s website.

The latest reimbursement promise builds on late August when Musk told a Tesla investor weighing whether to give Grok Bot access to his bank accounts, “If Grok Bot messes up, we will make you whole,” as Teslarati covered when SpaceXAI added its Finance integration. That promise goes further than the company’s consumer terms, which make users responsible for what their agents do and generally cap liability at the greater of fees paid or $100. Neither Thursday post says those terms have changed, so for now it remains a statement on X rather than a published policy.

The two posts matter to Tesla owners because Grok Bot is no longer limited to a phone. Tesla brought it into its vehicles on September 22, and it is now enabled across every Cybercab and the rest of the Model Y Robotaxi fleet, as noted when Teslarati looked at why Grok Bot may be the Cybercab’s real advantage. A rider who asks for groceries or a coffee order is relying on retailers that let the agent in. Amazon has now said it will not, and Musk’s answer is to route around it.

Amazon has not commented publicly on the block in the posts Teslarati reviewed, and it is unclear whether Musk will follow through on a rival store.

So, how many of you do the vast majority of shopping on Amazon and hate that you do? Comment and let us know your thoughts!

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