News
SpaceX Starship fires up three Raptor engines in prelude to high-altitude flight
Update: At 1:21am CDT (6:21 UTC) on October 20th, Starship SN8 ignited all three of its Raptors’ preburners, producing a spectacular fireball noticeably larger than the one produced during the rocket’s first October 19th preburner test. A mere two hours later, with no break in between, the steel rocket prototype fully ignited all three Raptor engines for the first time ever, likely producing thrust equivalent to ~90% of a nine engine Falcon 9 booster for a brief moment.
Crucially, aside from physically demonstrating Raptor’s multi-engine capabilities, Starship SN8 – already a first-of-a-kind prototype – completed and survived a static fire seemingly unscathed on its first attempt. If the data SpaceX gathers from the milestone is as good as the test appeared to be, the company could be just a few days away from installing Starship SN8’s recently-stacked nosecone, followed by a second triple-Raptor static fire test. If that second static fire goes well, SN8’s next task will be the first high-altitude Starship flight test.
Minutes after an adjacent highway was scheduled to reopen, SpaceX’s first high-altitude Starship prototype – serial number 8 – attempted what was likely the first multi-engine Raptor test ever.
At 6:01 am, October 19th, Starship SN8’s trio of Raptor engines were barely unleashed, producing a large fireball indicative of a ‘preburner’ ignition test. One of the most complex rocket engines ever developed, Raptor relies on a maximally efficient but temperamental “full-flow staged combustion” cycle (FFSC), a concise name for the many, many steps required to turn liquid propellant into thrust.
Adding additional difficulty, Raptor’s full-flow staged combustion necessitates ignition of gaseous oxygen and methane in the combustion chamber. Given that the Raptor-powered Starship spacecraft and Super Heavy booster exclusively use cryogenic liquid methane and oxygen, a major challenge posed by FFSC is the need to efficiently turn that ultra-cold propellant into hot gas almost instantaneously. This is where gas generators (or preburners) come in.
In a full-flow staged combustion engine, both oxidizer and fuel require their own separate turbopumps, which then require their own preburners to create the pressures needed to power those turbopumps and the gas the combustion chamber ignites to produce thrust. A step further, to enable high combustion chamber pressure like Raptor’s 300+ bar (~4400+ psi), those preburners need to produce gas at far higher pressures to account for energy losses as those gases wind their way through the engine’s plumbing.
As a result, preburners are possibly the single most stressed system in an engine like Raptor. Unsurprisingly, this has often lead SpaceX to separately test each engine’s preburners as a sort of partial static fire before the actual engine ignition test. This is the test Starship SN8 attempted in the early morning on October 19th, representing Raptor’s very first multi-engine ignition event.
Curiously, moments before preburner ignition, one of the three Raptor engines appeared to command an aggressive jet-like vent of liquid oxygen identical to a vent seen just a few hours prior during the first aborted preburner test. There’s thus a chance that only two of SN8’s three Raptor engines successfully started their preburners
Raptor is the first FFSC engine in the world to fly and – as far as the duration of lifetime testing and volume production goes – is almost certainly the most advanced of the three FFSC programs to graduate to static fire tests. In other words, given that SN8’s test campaign is the first time SpaceX has ever attempted to operate multiple adjacent Raptor engines at the same time, it’s not a huge surprise that progress towards the first three-engine static fire has been cautious and halting. Mirroring its Sunday/Monday testing, SpaceX will put Starship SN8 through another preburner and/or static fire attempt between 9pm and 6am CDT (UTC-5) on October 19/20. Even more 9-6 test windows are scheduled on October 21st and 22nd.
Meanwhile, not long after Starship SN8’s first preburner test was completed, SpaceX teams rolled a section of five steel rings inside a small windbreak and stacked the first truly functional nosecone – already outfitted with forward flaps – atop it. If Starship SN8 survives its first full triple-Raptor preburner and static fire tests, that new nosecone will likely be rolled to the launch pad for in-situ installation, topping off the rocket ahead of a spectacular 15 km (~50,000 ft) flight test.
A Tesla Semi caught fire in Hayward, California, which caused both directions of traffic to shut down for hours before being completely reopened early on Wednesday, the California Highway Patrol said.
The fire occurred just after 5:30 local time in Hayward on Tuesday, as the Semi caught fire in the southbound lanes of I-880 before CHP officials made the decision to shut down both lanes of traffic due to potential risks from hazardous chemical smoke.
There were no injuries reported.
🚨 A Tesla Semi reportedly caught fire, with California Highway Patrol confirming. The Semi was on I-880 SB
An estimated 5,000 to 7,000 semi-truck and large commercial vehicle fires occur on U.S. roadways every year
— TESLARATI (@Teslarati) October 28, 2026
The cause of the fire is currently unknown, as neither Tesla nor the CHP have not determined a cause.
However, some images taken before the Semi was completely destroyed by the fire seem to indicate this might have been an older unit, as it appears to be one of the designs that Tesla shipped as part of its pilot program, before revising it and starting mass production just a month ago.
@Tslachan From on of the videos looks like it’s an old Semi (not the refresh version that recently started production) https://t.co/KzwmR2kXow
— Area Under The Curve 🎗️ (@AreaUnderCurve) October 28, 2026
At the time of publication, CHP had not returned our request for a comment for additional details, including the Semi involved and any potential collaboration on an investigation between the CHP and Tesla. We will update this story when we hear back from them.
The southbound lanes were reopened at 3:30 a.m. on Wednesday, with the northbound lanes opening last night a few hours after the fire began. The CHP did state that the lithium batteries were “incredibly difficult to extinguish,” according to NBC Bay Area.
The truck’s driver said that the Semi caught fire, but he did not have an explanation.
An estimated 5,000 to 7,000 semi-truck and large commercial vehicle fires occur on U.S. roadways every year.
Tesla’s launch of the “Emergency Drive Away” function a few months back offered owners a safe option to evacuate an area if they were in reasonable danger. The function finally got its first use in the real world, but it appears it was by mistake.
A video shared by u/Joshalander in the r/TeslaLounge subreddit recorded the instance from his vehicle and said the incident took place in Austin this past weekend during the city’s F1 Race.
“Was charging around 6 AM this past Sunday in Austin before heading to the F1 race and heard a pop. Looked over and saw the new emergency drive-away feature in action. Genuinely felt bad for the dude when he got out and realized what happened, since he looked exhausted and only seemed to half-read the prompts.”
🚨 Here’s the first look at Tesla’s Emergency Drive Away function in action:
Apparently this driver accidentally enabled it and drove forward; you can see the Supercharger pull with the car.
Tesla said previously this would cost up to $25k if not used properly. https://t.co/B4qQRrsO6B
— TESLARATI (@Teslarati) October 28, 2026
Emergency Drive Away unlatches the Supercharger connector from the vehicle, but still causes damage to both the car and the Supercharger. Tesla has said that it will cost up to $25,000 in repairs to have everything fixed back to normal.
Additionally, the company said that if it were not used in an emergency situation, the driver of the vehicle who activated the Emergency Drive Away feature would be responsible for all repair costs.
Tesla constitutes the following situations as reasonable justifications for activating the feature:
- You face an immediate threat to your life or personal safety.
- You must leave the area immediately.
- Exiting the vehicle is unsafe.
- Unplugging the charge connector would unreasonably delay your departure or expose you to a risk to your personal safety.
After using the feature, Tesla requires the driver to schedule Service so the car can be inspected.
News
Tesla’s Cybercab battery design could make robotaxis even cheaper
Tesla built the Cybercab’s battery pack with spare room for a future switch to LFP.
Tesla built the Cybercab’s battery pack with empty space inside it on purpose, and the reason points to a cheaper robotaxi down the road.
Robert Sumpf, Tesla’s director of mechanical design engineering for battery modules and packs, said the extra room beside and beneath the Cybercab’s modules was left there so the company can move to lithium iron phosphate cells later. “So, we protected this pack to go to an even lower energy dense chemistry as we scale and need to bring LFP into the platform,” Sumpf said in a Cybercab deep dive with Munro Live.
The Cybercab runs on Tesla’s own 4680 cells with a nickel chemistry today. LFP cells store less energy for their size, so a straight swap would cut range. The reserved space lets Tesla add more LFP cells to make up the difference. In return, Tesla would get cells that cost less, run cooler and survive more charge cycles. LFP became the most used EV battery chemistry in the world last year.
Not all of that room was planned for a chemistry change. Lars Moravy, Tesla’s Vice President of Vehicle Engineering, said part of it exists because “we didn’t need as many batteries as we thought we did.” Tesla told Sandy Munro in early 2025 that it was targeting a Cybercab pack under 50 kWh with close to 300 miles of range.
The pack also breaks from the structural design Tesla used in some Model Y and Cybertruck builds. Instead of potting hundreds of cells into one block, the Cybercab uses four separate, individually sealed modules, so a bad module can be replaced without scrapping the whole pack. Sumpf was blunt about the older approach, giving the Model Y structural battery “a grade D” because it was hard to build and nearly impossible to repair. He estimated a fully structural pack gains about 10% more cell volume, but said “the issue is the service cost.”
That cost matters more for a car that rarely sits parked. Cybercab chief engineer Eric Earley said replacing an entire pack “before half a million miles is a killer on cost,” which is why remanufacturing and serviceability were built into the design from the start.
The same Munro Live tour produced Moravy’s admission that the Cybercab line at Giga Texas is now outpacing Robotaxi deployments, along with a look at the robotaxi’s unorthodox paint process. Tesla is aiming to deliver the first Cybercabs to outside customers by the end of 2026, though Elon Musk has said the vast majority will stay owned by Tesla and run as a transport service.
Sumpf did not give a date for an LFP version, name a cell supplier or say how a chemistry change would affect range. For now, the 4680 cars keep piling up: Texas DMV records from Tuesday list 544 Cybercabs authorized for Tesla’s Robotaxi fleet, more than the 507 Model Ys on the same roster for the first time.
Tesla Semi catches fire in California: what we know
Tesla’s ‘Emergency Drive Away’ function gets its first use in the real world
