News
SpaceX Starship fires up Raptor Vacuum engine twice in one hour
After weeks of exceptionally cautious buildup, SpaceX’s first orbital-class Starship prototype has repeatedly broken new ground tests in the first few hours of its first static fire test window.
SpaceX first installed Starship S20 on one of two suborbital launch and test stands more than two months ago. After almost six weeks of largely invisible work, longer than any other new Starship prototype has spent inactive at Starbase launch facilities, Ship 20 came to life for the first time during a ‘pneumatic proof’ test completed on September 27th. Two days later, put the Starship through a complex cryogenic proof test, loading supercool liquid nitrogen instead of ambient-temperature gas and simulating the thrust of six Raptor engines with hydraulic rams.
According to CEO Elon Musk, Ship 20 passed its first ‘cryoproof’ without issue, opening the door for static fire testing with real methane and oxygen (LCH4/LOx) propellant and Raptor engines. However, for unknown reasons, it would ultimately take SpaceX more than three weeks of additional work to prepare Starship S20 for its first engine-involved test.
On October 19th, near the end of a seven-hour test window, Starship S20 sort of fired up for the first time, completing what is known as a preburner test. Effectively the first half of static fire test without full ignition, it was nevertheless the first time a Raptor Vacuum engine was operated on a Starship prototype. Originally, based on road closures scheduled with Cameron County, Texas, that preburner test and associated static fire testing was initially scheduled to begin as early as Friday, September 31st.
SpaceX continued to file for and cancel closures throughout the next week, culminating in a few local residents receiving a routine safety notice about a possible test on October 13th. That attempt was canceled soon after and SpaceX ultimately distributed alerts for tests on October 14th and October 18th. Ship 20’s first preburner test was completed on the 19th, followed by another soon-to-be-rescinded notice on the 20th.
Finally, after perhaps the windiest road yet for a Starship from cryoproof to static fire, Starship S20 sailed through a static fire test flow on October 21st and ultimately fired up for the first time ever at 7:16 pm CDT (00:16 UTC). In perfect opposition to weeks of unprecedentedly slow testing, Starship S20 not only completed its first true static fire early in the test window, but it completed the first on-vehicle static fire of a Raptor Vacuum engine and then, just over an hour later, performed a second static fire – this time simultaneously igniting both a Raptor Vacuum and Raptor Center (sea-level-optimized) engine. Aside from also marking the first time that two Raptor variants have been simultaneously fired on the same vehicle, Starship S20’s two-test surprise was technically the fastest back-to-back static fire SpaceX has ever completed, beating Starship SN9 by about 15 minutes.
Back in January 2021, SN9 completed an unprecedented three back-to-back-to-back Raptor static fires in less than 100 minutes as part of what Musk described as “[a day] about practicing Starship engine starts.” SN9 ultimately completed two of those tests in 75 minutes, setting a niche but still impressive turnaround record. Starship S20, however, managed two static fires in 62 minutes on October 21st.
With any luck, Ship 20’s unexpected first-test milestones will mark the start of a more energetic period for the orbital-class prototype, potentially building up to the first Starship static fire with more than three Raptors and the first test with all six engines installed. Super Heavy Booster 4 is also well overdue for its own proof and static fire test campaign, virtually all of which will be new territory for SpaceX.
Tesla has reached a notable benchmark in its autonomous driving program after its Robotaxi fleet surpassed one million miles of unsupervised operation. The company made the announcement during its Cybercab event in Austin on September 3.
Tesla Vice President of AI Ashok Elluswamy told attendees he was happy to report the fleet had achieved one million miles of unsupervised Robotaxi operation as a testament to safety.
The new total marked a sharp increase from the 380,000 unsupervised miles Tesla disclosed during its second-quarter 2026 earnings update in late July.
In roughly six weeks, the company added about 620,000 miles. That acceleration followed Tesla’s decision to remove in-vehicle safety monitors from most of its operations outside the San Francisco Bay Area.
Credit: Tesla
Tesla first launched Robotaxi service in Austin in June 2025 with safety drivers present. It later began fully unsupervised rides and expanded into Dallas, Houston, Miami, Orlando, and Tampa. The San Francisco Bay Area remains the exception, where a safety monitor still rides in the vehicle under California permitting rules.
The company has not released a city-by-city breakdown of the one million unsupervised miles.
The milestone arrived as Tesla began offering public Cybercab rides in Austin. The purpose-built vehicle has no steering wheel or pedals and is designed only for autonomous ride-hailing. Production versions joined the existing fleet of modified Tesla vehicles already operating in the service.
Tesla’s unsupervised mileage is growing at a double-digit weekly rate according to earlier company comments, yet its fleet size remains modest compared with established competitors. Waymo has accumulated more than 200 million fully autonomous rider-only miles. Tesla has described its own unsupervised operations as having recorded zero notable incidents in the period leading up to the July update.
The one-million-mile figure reflects Tesla’s shift from supervised testing to broader driverless service in multiple states. It also highlights the company’s strategy of using both existing Model Y vehicles and the new Cybercab to scale its network.
Credit: Tesla
Whether the rapid recent growth continues will depend on further city expansions, regulatory approvals, and the performance of the purpose-built Cybercab in everyday paid rides. Tesla has not specified how many of the latest miles involved the new vehicle versus the rest of the fleet.
The announcement underscores Tesla’s progress toward a larger robotaxi network while illustrating the remaining gap in total autonomous experience relative to longer-operating rivals.
Tesla AI lead Ashok Elluswamy said this week that 24-hour Robotaxi service is close. Replying on X to a rider who wanted Cybercab trips all night, he wrote that the capability would arrive “next month or so” once “the next tech to merge on the v15 plan” is ready.
The comment landed on September 4, one day after Tesla opened public Cybercab rides in Austin. It is the clearest near-term timeline yet for overnight unsupervised operation. Tesla’s paid Robotaxi network currently runs from 6 a.m. to 10 p.m. seven days a week across Austin, Dallas, Houston, Miami, Orlando, and Tampa.
next month or so. the next tech to merge on the v15 plan will enable it.
— Ashok Elluswamy (@aelluswamy) September 4, 2026
That 16-hour window is shorter than the 6 a.m. to 2 a.m. schedule the company used for much of the prior year.
Elluswamy did not name the specific feature or say whether the change would apply first to purpose-built Cybercabs, the existing Model Y fleet, or both. He also offered no city-by-city rollout list. The link to Full Self-Driving v15 is nevertheless significant.
Tesla has described v15 as a step-change architecture with seven parallel improvement tracks and roughly ten times more parameters than earlier builds. Early versions of that software already operate on the Robotaxi fleet and contain about 40 percent of the planned gains.
By July 2026, the unsupervised fleet had logged more than 380,000 miles across six cities in two states with what the company called an impeccable safety record and no notable incidents caused by the vehicles themselves. Tesla has repeatedly argued that camera-based end-to-end neural networks, rather than extra sensors, are the core of the solution.
Overnight service would test that claim in lower-light conditions and would also raise vehicle utilization, a key variable for Robotaxi unit economics. The company has already begun using public Superchargers at night and is building dedicated Robotaxi charging sites.
Riders have asked why software must change if the cars already drive in the dark. The practical answer appears to be reliability and scale: Tesla has held back mass expansion until more of the v15 stack is merged, citing the need for higher confidence before putting thousands of unoccupied vehicles on streets around the clock.
If the next module arrives on the timetable Elluswamy sketched, 24-hour service could begin in October 2026 in at least some markets.
That would mark a shift from a daytime-bounded pilot to a service that can run whenever demand exists, including the late-night hours that have so far remained out of reach.
Tesla is beginning to roll out Full Self-Driving Supervised v14.3.9 with a new active safety layer that can take control even when the driver is operating the car manually.
Tesla AI said the software can activate FSD on the driver’s behalf when an imminent collision is detected and Automatic Emergency Braking may not be enough. It may also engage if the system detects heavy distraction or an accidental FSD disengagement.
FSD Supervised v14.3.9 starting to roll out shortly
This release includes a new active safety feature set: FSD Supervised can now activate on your behalf when an imminent collision is detected and Automatic Emergency Braking (AEB) may not be enough.
It may also engage if we…
— Tesla AI (@Tesla_AI) September 4, 2026
The capability is essentially Automatic Collision Evasion. However, unlike conventional AEB, which mainly applies the brakes in a straight line, this feature can use steering, braking, and acceleration together if the car calculates that stopping alone will not prevent impact and a safer path exists. The system may change lanes or move toward a shoulder when conditions allow, then continue driving after the immediate threat is handled rather than simply coming to a stop.
The intervention is meant as a last-resort safety net, not a replacement for attentive driving.
Tesla Full Self-Driving v14.3.7 early review: FSD saved me from an accident
Tesla’s own description still frames FSD as supervised assistance. Secondary reports on internal release notes say the feature can fire while the car is being driven manually if cabin-camera monitoring suggests the driver is not sufficiently attentive, such as reaching toward the back seat, or if FSD appears to have been turned off unintentionally.
After the emergency maneuver, the car is expected to alert the driver and request a return to manual control.
The safety case is straightforward. Many collisions happen in the last second because a driver is looking away, fumbles a control, or faces an obstacle that braking cannot fully solve. A system that can both recognize that AEB is insufficient and execute a coordinated evasive path can reduce those remaining high-severity events.
Re-engaging after accidental disengagement also addresses a practical failure mode: a small steering nudge that drops FSD at the worst moment. The advantage is a background safety net that uses the same vision stack already running in v14, instead of leaving the car solely to emergency braking once the driver is no longer in command.
The feature still depends on FSD being enabled and, according to reports, an active FSD purchase or subscription. It does not make the vehicle unsupervised. Drivers remain responsible, and Tesla has not published how often the system is expected to intervene or how it will handle false positives.
If the rollout is conservative and the false-alarm rate stays low, the update is a meaningful step: FSD is no longer only a feature the driver turns on. In the rare moments when disaster is already forming, it can step in.
Tesla crosses major Unsupervised Self-Driving milestone
Tesla Robotaxi will be a 24/7 service: here’s when
