Connect with us

News

NASA’s SLS Moon rocket almost aces vital prelaunch test on 7th try

Published

on

Following several incomplete attempts in April, June, August, and September, NASA’s first Space Launch System (SLS) Moon rocket has almost aced a vital prelaunch test on the seventh try.

NASA says that “all objectives were met” during the ten-hour test, which wrapped up around 4:30 pm EDT (20:30 UTC) on Wednesday, September 21st. Despite the rocket running into multiple additional issues, some old and others new, the agency was confident enough in the preliminary results of the wet dress rehearsal (WDR) – deemed a “cryogenic demonstration test” – to reaffirm that it’s still working towards a third launch attempt as early as September 27th.

That launch date is not set in stone, but NASA also hasn’t ruled out the window after the latest round of SLS testing. The agency will host a press conference on Friday, September 23rd, to provide its final decision and offer more details about the seventh wet dress rehearsal.

Despite NASA’s apparent confidence after the test, which was admittedly smoother than most previous SLS tests at the launch pad, it was far from smooth. The immediate story of the “cryogenic demonstration test” dates back to the SLS Artemis I rocket’s second so-called “launch attempt” on September 3rd. During that attempt, the launch was aborted well before SLS was ready when NASA detected a major hydrogen fuel leak around one of the quick-disconnect umbilical panels that fuels and drains the rocket. Remote troubleshooting was unable to solve the problem, forcing NASA to stand down.

Advertisement

Over the last few weeks, teams inspected, tested, and repaired the faulty Tail Service Mast Umbilical (TSMU), preparing for a cryogenic proof test meant to verify that the issue was fixed. During that September 21st test, the TSMU still leaked significantly for the whole duration, but it did so more predictably and – unlike prior leaks – never violated the limits that would trigger a launch abort.

But near the end, a different umbilical panel developed a significant hydrogen leak that did violate those launch constraints, meaning that NASA would have likely had to stand down yet again if it had attempted to launch before completing additional testing. The test was completed successfully, but its goals and constraints were not the same as those facing a launch.

A NASA-developed rocket leaking hydrogen is unfortunately a tale as old as time. That the agency that struggled with hydrogen leaks throughout the 30-year career of the Space Shuttle appears to be just as flabbergasted by nearly identical problems on a new rocket – SLS – that has Shuttle ‘heritage’ on almost every square inch is not surprising, even if it is somewhat embarassing.

Liquid hydrogen fuel always has been and likely always will be a massive pain to manage in any rocket, but especially in a large rocket. As the smallest element in the universe, it is fundamentally leak-prone. Combined with the fact that it only remains liquid below the extraordinarily low temperature of -253°C (-423°F), generates ultra-flammable hydrogen gas as it continually attempts to warm to a more stable temperature, and naturally embrittles most metals, it’s an engineering nightmare by almost every measure.

Advertisement

For all that pain, hydrogen does provide rocket engineers exceptional efficiency when properly exploited, but even that positive aspect is often diminished by hydrogen’s ultra-low density. For rocket stages that have already reached orbit, hydrogen-oxygen propellant offers unbeatable efficiency. But for a rocket stage that will never be used in orbit, like the SLS core stage, hydrogen fuel is rarely worth the tradeoffs – a reality that SLS is unfortunately providing a strong reminder of.

Demonstrating the Groundhog Day-esque nature of NASA rockets and hydrogen leaks, the same leaky TSMU panel that aborted SLS’ September 3rd launch attempt (sixth WDR) and had to be fixed and retested on September 21st also caused a hydrogen leak that partially aborted the rocket’s third wet dress rehearsal attempt in April 2022. NASA then rolled the rocket back to the Vehicle Assembly Building (VAB), where workers spent almost two months inspecting and reworking the fuel TSMU and fixing other issues. During its first test (WDR #4) after rolling back to the pad in June, the same fuel TSMU leaked and NASA had to return the rocket to the VAB again to fix the problem.

The fuel TSMU then leaked on the SLS rocket’s first launch attempt (really WDR #5), but the problem was resolved and was not what caused NASA to stand down. It was, however, a primary reason behind NASA’s second aborted launch attempt (WDR #6). With any luck, the eighth time will be the charm.

Advertisement

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.

Advertisement
Comments

Lifestyle

California hits Tesla Cybercab and Robotaxi driverless cars with new law

California just gave police power to ticket driverless cars, including Tesla’s Cybercab fleet.

Published

on

By

Concept rendering of Tesla Cybercab being cited by CA Highway Patrol (Credit: Grok)

California DMV formally adopted new rules on April 29, 2026 that allow law enforcement to issue “notices of noncompliance”, or in other words, ticket autonomous vehicle companies when their cars commit moving violations. The rules take effect July 1, 2026, officially closes a regulatory gap that previously let driverless cars operate on public roads with nearly no traffic enforcement consequences.

Until now, state traffic law only applied to human “drivers,” which meant that when no person was behind the wheel, police had no mechanism to issue a ticket. Officers were limited to citing driverless vehicles for parking violations only. A well-known example came in September 2025, when a San Bruno officer watched a Waymo robotaxi execute an illegal U-turn and could do nothing but notify the company.

Under the new framework, when an officer observes a violation, the autonomous vehicle company is effectively treated as the driver. Companies must report each incident to the DMV within 72 hours, or 24 hours if a collision is involved. Repeated violations can result in fleet size restrictions, operational suspensions, or full permit revocation. Local officials also gained new authority to geofence driverless vehicles out of active emergency zones within two minutes and require a live emergency response line answered within 30 seconds.

Tesla Cybercab ramps Robotaxi public street testing as vehicle enters mass production queue

California’s new enforcement rules arrive at a pivotal moment for Tesla. The company is ramping Cybercab production at Giga Texas toward hundreds of units per week, targeting at least 2 million units annually at full capacity, while simultaneously pushing to expand its Robotaxi service to dozens of U.S. cities by end of 2026. Unsupervised FSD for consumer vehicles is currently targeted for Q4 2026, and when it arrives, Tesla’s fleet may not have a human to absorb legal accountability, under the July 1 rules.

Tesla has confirmed plans to expand its Robotaxi service to seven new cities in the first half of 2026, including Dallas, Houston, Phoenix, Miami, Orlando, Tampa, and Las Vegas, with the service already running without safety drivers in Austin. Musk has said he expects robotaxis to cover between a quarter and half of the United States by end of year.

Continue Reading

News

Tesla Model X shocks everyone by crushing every other used car in America

The Model X is one of Tesla’s flagship models, the other being the Model S. Earlier this year, Tesla confirmed it would discontinue production of both the Model S and Model X to make way for Optimus robot production at the Fremont Factory in Northern California.

Published

on

Credit: Tesla Asia | X

The Tesla Model X was the fastest-selling used vehicle in the United States in the first quarter of the year, crushing every other used car in America.

iSeeCars data for the first quarter shows that the Model X was the fastest-selling used car, lasting just 25.6 days on the market on average, two days better than that of the second-place Lexus RX 350h. The Cybertruck, Model Y, and Model S, in seventh, ninth, and thirteenth place, respectively, also made the list.

The Model X is one of Tesla’s flagship models, the other being the Model S. Earlier this year, Tesla confirmed it would discontinue production of both the Model S and Model X to make way for Optimus robot production at the Fremont Factory in Northern California.

Tesla brings closure to flagship ‘sentimental’ models, Musk confirms

Bringing closure to these two vehicles signaled the end of the road for the cars that have effectively built Tesla’s reputation for luxury and high-end passenger vehicles.

Relying on the sales of its mass market Model Y and Model 3, as well as leaning on the success of future products like the Cybercab, is the angle Tesla has chosen to take.

Teslas are also performing extremely well as a whole on the resale market. iSeeCars data shows that, “while the average price of a 1- to 5-year-old non-Tesla EV fell 10.3% in Q1 2026 year-over-year, the average price of a used Tesla was essentially flat at 0.1% lower across the same period. Traditional gas car prices dropped 2.8% during this same period.”

Additionally, market share for gas cars has dropped nearly 3 percent since the same quarter last year. Tesla has remained level, while the non-Tesla EV market share has increased 30 percent, mostly due to more models available.

Nevertheless, those non-Tesla EVs have seen their value drop by over 10 percent, while Tesla’s values have remained level.

Executive Analyst Karl Brauer said:

“Used electric vehicles without a Tesla badge have lost more than 10% of their value in the past year. This compares to stable values for Teslas and hybrids, and a modest 2.8% drop for traditional gasoline vehicles.”

Teslas, as well as non-luxury hybrids, are displaying the strongest resistance in the face of faltering demand, the publication says. But the more impressive performance is that of the Model X alone.

Tesla’s decision to stop production of the Model X may have played some part in the vehicle’s pristine performance in Q1. With the car already placed at a premium price point, used models are already more appealing to consumers. Perhaps second-hand versions were more than enough for those who wanted a Model X, and only a Model X.

Continue Reading

Cybertruck

Tesla Cybertruck’s head-scratching trim sold terribly, recall documents reveal

The head-scratching offering was only available for a few months, and evidently, it did not sell very well, which we all suspected. New recall documents on the vehicle from the National Highway Traffic Safety Administration (NHTSA) now reveal just how poorly it sold.

Published

on

Credit: Tesla

After Tesla decided to build a Rear-Wheel-Drive Cybertruck trim back in 2025, which was void of many features and only featured a small discount.

The head-scratching offering was only available for a few months, and evidently, it did not sell very well, which we all suspected. New recall documents on the vehicle from the National Highway Traffic Safety Administration (NHTSA) now reveal just how poorly it sold.

The recall deals with a potentially separating wheel stud and potentially impacts 173 Cybertruck units with the 18-inch steel wheels. The Cybertruck RWD was the only trim level to feature these, and the 173 potentially impacted units represent a portion of the population of pickups. Therefore, it’s not the entire number of RWD Cybertruck sold, but it could show how little interest it gathered.

The NHTSA document states:

“On affected vehicles, higher severity road perturbations and cornering may strain the stud hole in the wheel rotor, causing cracks to form. If cracking propagates with continued use and strain, the wheel stud could eventually separate from the wheel hub.”

Only 5 percent are expected to be impacted, meaning less than 10 units will have the issue if the NHTSA and Tesla estimates are correct. Nevertheless, the true story here is how terribly the RWD Cybertruck sold.

Tesla ended production and stopped offering the RWD Cybertruck to customers last September. For just $10,000 less than the All-Wheel-Drive trim, Tesla offered the RWD Cybertruck with just one motor, textile seats instead of leather, only 7 speakers instead of 15, no Rear Touchscreen, no Powered Tonneau Cover for the truck bed, and no 120v/240v outlets.

Tesla brings closure to head-scratching Cybertruck trim

For just $10,000 more, at $79,990, owners could have received all of those premium features, as well as a more capable All-Wheel-Drive powertrain that featured Adaptive Air Suspension. The discount simply was not worth the sacrifices.

Orders were few and far between, and sources told us that when it was offered, sales were extremely tempered because customers could not see the value in this trim level.

Even Tesla’s most loyal supporters thought the offering was kind of a joke, and the $10,000 extra was simply worth it.

Cybertruck RWD Recall by Joey Klender

Continue Reading