Connect with us

News

NASA scrubs first SLS Moon rocket launch attempt

A beautiful start to an unfortunately unfruitful day. (Richard Angle)

Published

on

NASA has scrubbed the first attempted launch of its Space Launch System (SLS) Moon rocket after running into multiple issues, one of which could not be solved in time.

The delay is bad news for the tens to hundreds of thousands of tourists who traveled to Cape Canaveral, Florida to witness the launch in person. Worse, by NASA’s own implicit admission, there’s a good chance the main problem SLS encountered could have already been dealt with and rectified in advance of the launch attempt if the space agency had finished testing the rocket earlier this summer.

Ultimately, that omission turned the first SLS launch attempt into more of a continuation of the rocket’s first four wet dress rehearsal (WDR) attempts, none of which ended as expected. NASA engineers will now have to decide how to proceed and whether the SLS rocket can be made ready in time for another launch attempt on September 2nd or 5th. If not, the next opportunity could be weeks away.

As far as SLS test operations go, the August 28/29th launch attempt was fairly ordinary, with the rocket running into multiple issues – a few minor, a few significant, and one identical to a previous problem. The first problem – a hydrogen leak near the SLS rocket’s base – came after a risk of lightning delayed the start of propellant loading by more than an hour. A very similar, if not identical, hydrogen fuel leak had already occurred during official wet dress rehearsal testing in April and July.

That leak was fixed on the fly by properly chilling all related systems, and propellant loading was eventually completed – albeit a few hours late thanks to inclement weather. Shortly after, there were reports of a crack that needed careful analysis. Only later did NASA specify that the suspected crack was in the rocket’s foam insulation rather than its structures, the latter of which could have been a catastrophic problem.

Advertisement

Around the same time, the true showstopper of the day occurred when NASA attempted to chill the SLS Core Stage’s four RS-25 engines, all of which flew several times aboard reusable Space Shuttle orbiters. Three engines performed (mostly) as expected, flowing a bit of liquid hydrogen fuel to cool themselves down, but one – engine #3 – was never able to make progress toward the optimal temperature needed for ignition (~5°C/~41°F). After hours of remote troubleshooting attempts, no progress had been made, and NASA ultimately decided to scrub the launch attempt at T-40 minutes to liftoff.

Over the course of four separate wet dress rehearsal attempts in April and June 2022, NASA was never able to test the core stage’s engine chill capabilities. In a post-scrub press conference, Jim Free – NASA’s Associate Administrator of the Exploration Systems Development Division – revealed that all four engines were warmer than intended, further confirming that skipping a fully nominal wet dress rehearsal was likely a mistake. Clear and present evidence aside, Free stated that he and other executives still believed skipping that test was the right decision, claiming that ending explicit WDR testing reduced the number of times the rocket needed to be moved on its transporter.

Making the situation even harder to explain, Artemis I Mission Manager Mike Sarafin revealed in the conference Q&A that Boeing had changed the design of parts of the SLS engine chill (bleed) system after the Core Stage finally conducted a nominal static fire test at Mississippi’s Stennis Space Center. Completed in March 2021, the SLS rocket then sat inside NASA’s Kennedy Space Center, Florida Vehicle Assembly Building (VAB) for a full year before attempting its first wet dress rehearsal tests at the launch pad.

The first round of three WDRs were not as smooth as NASA expected and instead uncovered three relatively small issues: a hydrogen leak, a single faulty upper stage valve, and problems with a ground supply of nitrogen gas. Those small issues led NASA to roll SLS back to the VAB for repairs, incurring a minimum multi-week delay that stretched into two months. SLS also failed to complete a fourth WDR attempt in July 2022, but NASA decided to overlook the rocket parts and phases of preflight operations that were never actually tested as planned, one of which was the engine chill system.

If NASA cannot fix the RS-25 chill system within the next few days, it will be forced to roll the entire rocket and mobile launch platform back to the VAB to – at a minimum – replace its flight termination system (FTS). The US Eastern Range requires that all rocket FTS systems be tested no more than 15 days before launch, and NASA was able to secure special permission for a gap of up to 25 days. However, because Boeing’s Core Stage design places the FTS system in a location that is reportedly inaccessible at the pad, the entire SLS rocket will need to roll back to the VAB to have its FTS systems “retested” after that period.

Advertisement

As a result, NASA’s SLS launch debut will be delayed by several weeks (at best) if it can’t recycle for another attempt on September 2nd or 5th. The next window runs from September 20th to October 4th, but the SLS rocket took 10 days to go from its latest rollout to first launch attempt – a figure that doesn’t include the time required to remove the rocket from the pad, roll it back to the VAB, and conduct any necessary repairs or tests while back in the bay. If NASA can’t fix the engine problem at the pad by September 3rd or 4th, the true delay could be more like 4-6 weeks.

With any luck, that won’t happen, but it’s clear that a lot of stress and discomfort could have been avoided if NASA had gone into its first launch attempt knowing that its SLS rocket was truly ready.

(Richard Angle)
(Richard Angle)
(Richard Angle)

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

Elon Musk

Tesla CEO Elon Musk reveals new details about Robotaxi rollout

The first Tesla Robotaxi unit was spotted in Austin earlier today, and CEO Elon Musk is revealing some cool new details.

Published

on

Tesla CEO Elon Musk has revealed new details about the company’s relatively imminent rollout of the Robotaxi platform as the suspected launch date of June 12 continues to near.

Earlier today, the first video showing the first driverless Tesla Robotaxi in Austin was shared on X, just a day after the City officially listed the company as an autonomous vehicle operator on its website. Tesla is listed as a company in the “Testing” phase.

The initial details of the Robotaxi are being revealed by Musk, who is carefully releasing small tidbits that seem to show the capabilities of the entire Tesla fleet, and not necessarily just the vehicles that will be involved in the initial rollout in Austin.

First Tesla driverless robotaxi spotted in the wild in Austin, TX

His first tidbit is one that many Tesla owners and fans will already know: many Teslas are capable of this driveless performance, but Full Self-Driving is not yet refined to the point where the software is quite ready to handle it. Current versions are robust, but not prepared for driverless navigation. The hardware, however, will enable Teslas to be Robotaxis, even if they’re already purchased by owners:

This is one of the biggest advantages Tesla has over other vehicle makers. Simply put, the Over-the-Air software updates that will roll out to FSD users will eventually make their cars into Robotaxis as well.

However, Musk shed some details on the version of FSD that is being run in these new Robotaxis that were spotted. Musk said that the version these Robotaxis are running is a new version, but will soon “merge to main branch.”

There is also an even newer version that has four times the parameters as this newer version that the test-stage Robotaxis are using, but Musk admits that this needs significant refinement before it is released to the public.

As of now, Tesla is simply teasing the actual launch date of the Robotaxi program, but Bloomberg reported earlier this month that it will occur on June 12.

Continue Reading

News

First Tesla driverless robotaxi spotted in the wild in Austin, TX

The short clip suggests that Tesla may be ramping up its preparations for its robotaxi rollout in Austin.

Published

on

Credit: @TerrapinTerpene/X

A recent video posted on X has provided a first look at Tesla’s driverless robotaxi, which is expected to be deployed in Austin, Texas, this month. The vehicle was a new Tesla Model Y, which was followed by what appeared to be a manned chase car.

The short clip suggests that Tesla may be ramping up its preparations for its robotaxi rollout in Austin.

The First Robotaxi Sighting

It was evident from the short clip that the Tesla robotaxi was operating completely driverless. In the video, which was posted on X by @TerrapinTerpene, the driverless Tesla could be seen confidently making a turn. The vehicle looked and behaved like any other car on the road, save for the fact that there was no one in the driver’s seat.

Interestingly enough, the short video also provided a teaser on where Tesla will place its “robotaxi” logo on its self-driving cars. Based on the video, the robotaxis’ logo will be tastefully placed on the front doors, making the vehicles look sleek and clean.

Initial Rollout Imminent

Recent reports have suggested that Tesla is already starting the testing phase of its robotaxi service in Austin, Texas. Expectations are also high that Tesla’s initial fleet of self-driving vehicles will be utilizing a lot of teleoperation to ensure that they operate as safely as possible.

Advertisement

Updates to Austin’s official website recently have hinted at Tesla’s robotaxi launch. Just this Monday, Tesla was listed as an autonomous vehicle (AV) operator on Austin’s official Department of Motor Vehicles (DMV). Other AV operators listed on the site are Waymo and Zoox, among others.

Elon Musk, for his part, has noted that by the end of June, the public in Austin should be ready to take rides in Tesla robotaxis without an invitation. He also noted in late May that Tesla has been busy testing driverless cars on Austin’s city streets without any incidents.

Continue Reading

News

Tesla Model Y proudly takes its place as China’s best-selling SUV in May

The Model Y edged out competitors like the BYD Song Plus.

Published

on

Credit: Tesla China

The Tesla Model Y claimed its position as China’s best-selling SUV in May, with 24,770 units registered, according to insurance data from China EV DataTracker

The Model Y edged out competitors like the BYD Song Plus, which recorded 24,240 registrations, as well as Geely’s gasoline-powered Xingyue L, which took third place with 21,014 units registered, as noted in Car News China report.

Return To The Top

The Model Y’s return to the top of China’s SUV market follows a second-place finish in April, when it trailed the BYD Song Plus by just 684 units. Tesla China had 19,984 new Model Y registrations in April, while BYD had 20,668 registrations for the Song Plus. 

https://twitter.com/daltybrewer/status/1932171519817621536

For the first five months of 2025, Tesla sold 126,643 Model Ys in China, outpacing the Song Plus at 110,551 units and BYD’s Song Pro at 80,245 units. This is quite impressive as the new Tesla Model Y is still a premium vehicle that is significantly more expensive than a good number of its competitors.

Year-Over-Year Challenges

Despite its SUV crown, Tesla’s year-over-year performance in China is still seeing headwinds. May sales totaled 38,588 units, a 30% year-over-year decline. From January to May, Tesla delivered 201,926 vehicles in China, a 7.8% drop year-over-year. These drops, however, are notably affected by the company’s changeover to the new Model Y in the first quarter.

Advertisement
https://twitter.com/Tesla/status/1932171187700084910

Exports from Tesla’s Shanghai Gigafactory also fell, with 90,949 vehicles being shipped from January to May 2025. This represents a decline of 33.4% year-over-year, though May exports rose 33% to 23,074 units.

China’s electric vehicle market, meanwhile, showed robust growth. Total NEV sales, which includes battery electric vehicles (BEVs) and plug-in hybrids (PHEVs), reached 1,021,000 units in May, up 28% year-over-year. BEV sales alone hit 607,000 units, a 22.4% increase.

Considering the fact that China’s BEV market is extremely competitive, the Tesla Model Y’s rise to the top of the country’s SUV rankings is extremely impressive.

Continue Reading

Trending