News
SpaceX Starship test tank survives first two nights of stress testing
SpaceX’s newest Starship test tank has survived the first two nights of stress testing, pushing the steel tank one step closer to a destructive finale.
Known as Starship SN7.1, the new tank – aside from one critical difference – is similar to Starship SN2 (pictured above), a full-scale prototype SpaceX repurposed into a test tank in March 2020. SN2 served to test improvements made to the design of Starship’s “thrust puck,” a dense steel cone that must transmit the thrust of three Raptor engines through the rest of the rocket. Much like SN2, SN7.1 is a test tank with a focus on the behavior of Starship’s engine section under extreme loads at cryogenic temperatures.
Unlike SN2, however, SN7.1 is built almost entirely out of a new steel alloy – closer to 304L than the 301 stainless used on all previous prototypes.


SpaceX rolled the tank to the launch site and pressurized it with cryogenic liquid nitrogen on September 10th as part of a routine “cryo proof” acceptance test. SN7.1 appeared to complete that proof without issue, exhibiting no leaks or unusual behavior, and likely reached pressures of 7.5-8 bar (~110-120 psi) before detanking.
Over the next three days, SpaceX inspected the test tank, relocated it to a more capable (and expensive) test stand, and connected hydraulic rams (used to mechanically simulate engine thrust) to its thrust puck.

Around midnight on September 15th, SpaceX kicked off the first round of SN7.1 stress testing, repeatedly loading and unloading the tank with liquid nitrogen. While it’s impossible to visually confirm the use of the stand’s hydraulic rams, it’s safe to assume that SpaceX used them to stress SN7.1’s thrust puck while chilled to cryogenic temperatures. The new steel alloy SpaceX is using on SN7.x and prototypes SN8 and beyond is designed to be less brittle at cryogenic temperatures, nominally ensuring that flawed or aged Starship tanks leak before they burst or explode.
Aside from the obvious triple-Raptor thrust simulation, SpaceX likely also simulated thrust from one or two Raptors to verify the new design’s ability to survive asymmetric thrust in engine-out scenarios. Ultimately, SN7.1 made it through the night without obvious issues and there have been no signs of leak-fixing today, suggesting that the tank performed well. SpaceX has a second SN7.1 test period scheduled to begin on September 17th, as well as backups on the 15th, 16th, 20th, and 21st. More likely than not, SN7.1’s next test will end when the tank is intentionally pressurized to failure.
Update: SpaceX has kicked off another night of SN7.1 stress testing, beginning almost as soon as the nine-hour window opened (9pm CDT (UTC-5) on September 15th). As of midnight, the company has already put the test tank through one cycle, rapidly filling and pressurizing it with liquid nitrogen before detanking. It remains to be seen if the company will continue testing this window, which closes at 6am on Wednesday. There is also a chance that SpaceX will intentionally pressurize SN7.1 to failure tonight, although it’s much more likely that the tank will be returned to a cheaper, simpler transport stand rather than risking damage to a new launch mount.
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Investor's Corner
Tesla stock closes at all-time high on heels of Robotaxi progress
Tesla stock (NASDAQ: TSLA) closed at an all-time high on Tuesday, jumping over 3 percent during the day and finishing at $489.88.
The price beats the previous record close, which was $479.86.
Shares have had a crazy year, dipping more than 40 percent from the start of the year. The stock then started to recover once again around late April, when its price started to climb back up from the low $200 level.
This week, Tesla started to climb toward its highest levels ever, as it was revealed on Sunday that the company was testing driverless Robotaxis in Austin. The spike in value pushed the company’s valuation to $1.63 trillion.
Tesla Robotaxi goes driverless as Musk confirms Safety Monitor removal testing
It is the seventh-most valuable company on the market currently, trailing Nvidia, Apple, Alphabet (Google), Microsoft, Amazon, and Meta.
Shares closed up $14.57 today, up over 3 percent.
The stock has gone through a lot this year, as previously mentioned. Shares tumbled in Q1 due to CEO Elon Musk’s involvement with the Department of Government Efficiency (DOGE), which pulled his attention away from his companies and left a major overhang on their valuations.
However, things started to rebound halfway through the year, and as the government started to phase out the $7,500 tax credit, demand spiked as consumers tried to take advantage of it.
Q3 deliveries were the highest in company history, and Tesla responded to the loss of the tax credit with the launch of the Model 3 and Model Y Standard.
Additionally, analysts have announced high expectations this week for the company on Wall Street as Robotaxi continues to be the focus. With autonomy within Tesla’s sights, things are moving in the direction of Robotaxi being a major catalyst for growth on the Street in the coming year.
Elon Musk
Tesla needs to come through on this one Robotaxi metric, analyst says
“We think the key focus from here will be how fast Tesla can scale driverless operations (including if Tesla’s approach to software/hardware allows it to scale significantly faster than competitors, as the company has argued), and on profitability.”
Tesla needs to come through on this one Robotaxi metric, Mark Delaney of Goldman Sachs says.
Tesla is in the process of rolling out its Robotaxi platform to areas outside of Austin and the California Bay Area. It has plans to launch in five additional cities, including Houston, Dallas, Miami, Las Vegas, and Phoenix.
However, the company’s expansion is not what the focus needs to be, according to Delaney. It’s the speed of deployment.
The analyst said:
“We think the key focus from here will be how fast Tesla can scale driverless operations (including if Tesla’s approach to software/hardware allows it to scale significantly faster than competitors, as the company has argued), and on profitability.”
Profitability will come as the Robotaxi fleet expands. Making that money will be dependent on when Tesla can initiate rides in more areas, giving more customers access to the program.
There are some additional things that the company needs to make happen ahead of the major Robotaxi expansion, one of those things is launching driverless rides in Austin, the first city in which it launched the program.
This week, Tesla started testing driverless Robotaxi rides in Austin, as two different Model Y units were spotted with no occupants, a huge step in the company’s plans for the ride-sharing platform.
Tesla Robotaxi goes driverless as Musk confirms Safety Monitor removal testing
CEO Elon Musk has been hoping to remove Safety Monitors from Robotaxis in Austin for several months, first mentioning the plan to have them out by the end of 2025 in September. He confirmed on Sunday that Tesla had officially removed vehicle occupants and started testing truly unsupervised rides.
Although Safety Monitors in Austin have been sitting in the passenger’s seat, they have still had the ability to override things in case of an emergency. After all, the ultimate goal was safety and avoiding any accidents or injuries.
Goldman Sachs reiterated its ‘Neutral’ rating and its $400 price target. Delaney said, “Tesla is making progress with its autonomous technology,” and recent developments make it evident that this is true.
Investor's Corner
Tesla gets bold Robotaxi prediction from Wall Street firm
Last week, Andrew Percoco took over Tesla analysis for Morgan Stanley from Adam Jonas, who covered the stock for years. Percoco seems to be less optimistic and bullish on Tesla shares, while still being fair and balanced in his analysis.
Tesla (NASDAQ: TSLA) received a bold Robotaxi prediction from Morgan Stanley, which anticipates a dramatic increase in the size of the company’s autonomous ride-hailing suite in the coming years.
Last week, Andrew Percoco took over Tesla analysis for Morgan Stanley from Adam Jonas, who covered the stock for years. Percoco seems to be less optimistic and bullish on Tesla shares, while still being fair and balanced in his analysis.
Percoco dug into the Robotaxi fleet and its expansion in the coming years in his latest note, released on Tuesday. The firm expects Tesla to increase the Robotaxi fleet size to 1,000 vehicles in 2026. However, that’s small-scale compared to what they expect from Tesla in a decade.
Tesla expands Robotaxi app access once again, this time on a global scale
By 2035, Morgan Stanley believes there will be one million Robotaxis on the road across multiple cities, a major jump and a considerable fleet size. We assume this means the fleet of vehicles Tesla will operate internally, and not including passenger-owned vehicles that could be added through software updates.
He also listed three specific catalysts that investors should pay attention to, as these will represent the company being on track to achieve its Robotaxi dreams:
- Opening Robotaxi to the public without a Safety Monitor. Timing is unclear, but it appears that Tesla is getting closer by the day.
- Improvement in safety metrics without the Safety Monitor. Tesla’s ability to improve its safety metrics as it scales miles driven without the Safety Monitor is imperative as it looks to scale in new states and cities in 2026.
- Cybercab start of production, targeted for April 2026. Tesla’s Cybercab is a purpose-built vehicle (no steering wheel or pedals, only two seats) that is expected to be produced through its state-of-the-art unboxed manufacturing process, offering further cost reductions and thus accelerating adoption over time.
Robotaxi stands to be one of Tesla’s most significant revenue contributors, especially as the company plans to continue expanding its ride-hailing service across the world in the coming years.
Its current deployment strategy is controlled and conservative to avoid any drastic and potentially program-ruining incidents.
So far, the program, which is active in Austin and the California Bay Area, has been widely successful.