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

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3 years ago

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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.

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.

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.

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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.

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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 to increase Full Self-Driving subscription price: here’s when

Published

5 hours ago

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January 24, 2026

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Credit: Tesla

Tesla will increase its Full Self-Driving subscription price, meaning it will eventually be more than the current $99 per month price tag it has right now.

Already stating that the ability to purchase the suite outright will be removed, Tesla CEO Elon Musk said earlier this week that the Full Self-Driving subscription price would increase when its capabilities improve:

“I should also mention that the $99/month for supervised FSD will rise as FSD’s capabilities improve. The massive value jump is when you can be on your phone or sleeping for the entire ride (unsupervised FSD).”

This was an expected change, especially as Tesla has been hinting for some time that it is approaching a feature-complete version of Full Self-Driving that will no longer require driver supervision. However, with the increase, some are concerned that they may be priced out.

$99 per month is already a tough ask for some. While Full Self-Driving is definitely worth it just due to the capabilities, not every driver is ready to add potentially 50 percent to their car payment each month to have it.

While Tesla has not revealed any target price for FSD, it does seem that it will go up to at least $150.

Additionally, the ability to purchase the suite outright is also being eliminated on February 14, which gives owners another reason to be slightly concerned about whether they will be able to afford to continue paying for Full Self-Driving in any capacity.

Some owners have requested a tiered program, which would allow people to pay for the capabilities they want at a discounted price.

Unsupervised FSD would be the most expensive, and although the company started removing Autopilot from some vehicles, it seems a Supervised FSD suite would still attract people to pay between $49 and $99 per month, as it is very useful.

Tesla will likely release pricing for the Unsupervised suite when it is available, but price increases could still come to the Supervised version as things improve.

This is not the first time Musk has hinted that the price would change with capability improvements, either. He’s been saying it for some time. In 2020, he even said the value of FSD would “probably be somewhere in excess of $100,000.”

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Tesla starts removing outright Full Self-Driving purchase option at time of order

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8 hours ago

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January 24, 2026

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(Credit: Tesla)

Tesla has chosen to axe the ability to purchase Full Self-Driving outright from a select group of cars just days after CEO Elon Musk announced the company had plans to eliminate that option in February.

The company is making a clear-cut stand that it will fully transition away from the ability to purchase the Full Self-Driving suite outright, a move that has brought differing opinions throughout the Tesla community.

Earlier this week, the company also announced that it will no longer allow buyers to purchase Full Self-Driving outright when ordering a pre-owned vehicle from inventory. Instead, that will be available for $99 per month, the same price that it costs for everyone else.

The ability to buy the suite for $8,000 for a one-time fee at the time of order has been removed:

This is a major move because it is the first time Tesla is eliminating the ability to purchase FSD outright for one flat fee to any of its vehicles, at least at the time of purchase.

It is trying to phase out the outright purchase option as much as it can, preparing people for the subscription-based service it will exclusively offer starting on February 14.

In less than a month, it won’t be available on any vehicle, which has truly driven some serious conversation from Tesla owners throughout the community.

There’s a conflict, because many believe that they will now lose the ability to buy FSD and not pay for it monthly, which is an attractive offer. However, others believe, despite paying $8,000 for FSD, that they will have to pay more money on top of that cost to get the unsupervised suite.

Additionally, CEO Elon Musk said that the FSD suite’s subscription price would increase over time as capabilities increase, which is understandable, but is also quite a conflict for those who spent thousands to have what was once promised to them, and now they may have to pay even more money.

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Tesla Robotaxi has a highly-requested hardware feature not available on typical Model Ys

These camera washers are crucial for keeping the operation going, as they are the sole way Teslas operate autonomously. The cameras act as eyes for the car to drive, recognize speed limit and traffic signs, and travel safely.

Published

11 hours ago

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January 24, 2026

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Credit: David Moss | X

Tesla Robotaxi has a highly-requested hardware feature that is not available on typical Model Ys that people like you and me bring home after we buy them. The feature is something that many have been wanting for years, especially after the company adopted a vision-only approach to self-driving.

After Tesla launched driverless Robotaxi rides to the public earlier this week in Austin, people have been traveling to the Lone Star State in an effort to hopefully snag a ride from one of the few vehicles in the fleet that are now no longer required to have Safety Monitors present.

BREAKING: Tesla launches public Robotaxi rides in Austin with no Safety Monitor

Although only a few of those completely driverless rides are available, there have been some new things seen on these cars that are additions from regular Model Ys, including the presence of one new feature: camera washers.

With the Model Y, there has been a front camera washer, but the other exterior “eyes” have been void of any solution for this. For now, owners are required to clean them manually.

In Austin, Tesla is doing things differently. It is now utilizing camera washers on the side repeater and rear bumper cameras, which will keep the cameras clean and keep operation as smooth and as uninterrupted as possible:

These camera washers are crucial for keeping the operation going, as they are the sole way Teslas operate autonomously. The cameras act as eyes for the car to drive, recognize speed limit and traffic signs, and travel safely.

This is the first time we are seeing them, so it seems as if Safety Monitors might have been responsible for keeping the lenses clean and unobstructed previously.

However, as Tesla transitions to a fully autonomous self-driving suite and Robotaxi expands to more vehicles in the Robotaxi fleet, it needed to find a way to clean the cameras without any manual intervention, at least for a short period, until they can return for interior and exterior washing.

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