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SpaceX’s Starship Raptor Vacuum engine plans laid out by CEO Elon Musk

A 2016 render of Raptor Vacuum. Much has changed about the engine's design in the three years since, but SpaceX is still pursuing a vacuum variant. (SpaceX)

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Elon Musk says that SpaceX Starship engine upgrades are on track to begin static fire tests of a Raptor Vacuum variant as few as a “couple months” from now.

Designed to enable more efficient performance in thin atmosphere or vacuum, Musk admitted that the first version(s) of Raptor Vacuum (RVac) will likely be a compromise between efficiency and speed of development. Nevertheless, the faster SpaceX can prepare Raptor Vacuum for flight, the easier it will be for Starship to begin serious (sub)orbital flight tests.

As it turns out, SpaceX’s first and only official render of Raptor – published in September 2016 – showed the engine’s vacuum-optimized variant. In the years since, CEO Elon Musk has vacillated between keeping the vacuum engines as a central Starship feature and simply replacing them with regular sea level Raptors to expedite the spacecraft’s debut. The 2016 and 2017 vehicles featured a mixture of vacuum and sea-level engines, whereas Musk revealed a vehicle with sea-level engines only in 2018.

Known as the Interplanetary Transport System in 2016, the ship featured six vacuum Raptors and 3 SL engines. (SpaceX)
In 2017, Big Falcon Spaceship shrunk and changed to 4 x RVac and 3x x Raptor SL engines. (SpaceX)
In 2018, Musk decided to sidestep vacuum engines entirely, moving to 7 SL Raptors. (SpaceX)

Perhaps less than a month after Musk’s September 2018 presentation, the SpaceX CEO made the decision to radically redesign the vehicle – newly christened Starship and Super Heavy – by moving from a carbon composite aerostructure to stainless steel. At first, the seven SL Raptors remained a part of the design, but Musk took to Twitter in 2019 to indicate that SpaceX had changed gears again and had reprioritized Raptor Vacuum development.

This came as a bit of surprise and it should go without saying that there’s a significant chance that Musk/SpaceX will oscillate in the opposite direction once again before Raptor Vacuum is actually ready for flight. This time, though, Musk has sketched out a development schedule and strategy that suggests SpaceX is much more serious this time.

Most notably, Musk claims that the first Raptor Vacuum prototype could be ready for static fire testing just a “couple months” from now, an immensely ambitious schedule for any large liquid rocket engine development program. Nevertheless, Musk did indicate that the “V1.0” Raptor Vacuum design would be significantly compromised and “suboptimal”, an intentional decision to prioritize the engine’s “speed of development”.

Even then, Musk believes that the first variant – featuring a shortened bell nozzle – could still be up to 12% more efficient than sea level Raptors and thus already 70-80% of the way to the physical limit of methane-oxygen rocket efficiency.

A sea-level Raptor engine is static-fired at SpaceX’s McGregor, TX test facilities. (SpaceX)

On a positive note, shrinking V1.0 Raptor Vacuum’s nozzle a bit from its nominal length will likely mean that SpaceX can static fire fully-integrated engines at its McGregor, TX test facilities, critical for speedy development. If not, the company has experience with alternatives through Merlin Vacuum, which can only be tested on the ground with its lengthy nozzle detached. This method just makes it dramatically harder to optimize a vacuum nozzle design, as full-scale, flight-like testing is nearly impossible if a given vacuum engine can’t be tested on the ground with said nozzle installed.

Vacuum engines need such large and unwieldy nozzles in order to make them as efficient as possible. In a very simplistic sense, a rocket engine nozzle directs the flow of superheated, ultrafast gases in order to squeeze as much momentum transfer as possible out of available propellant. The lower the pressure of the surrounding atmosphere is, the more those gases will expand immediately after leaving the nozzle – giant vacuum nozzles simply try to harness the additional momentum available from that extra expansion. This is why rocket exhausts appear to spread and thin out as launch vehicles reach higher and higher altitudes.

A Falcon 9 upper stage’s vacuum nozzle glows white hot during an orbital MVac burn. (SpaceX)

In this sense, the perfect theoretical vacuum nozzle is quite literally infinitely long. The job of vacuum rocket engineers is to find the perfect balance between that impractical theoretical perfection and the limits of real-world materials and dynamics. In theory, SpaceX’s sea-level Raptor engines have already been designed to operate in vacuum conditions, while the engine’s closed-cycle design and regeneratively (i.e. propellant) cooled nozzle should apply well to a vacuum design.

If SpaceX is lucky, there will be few roadblocks in the way of simply lengthening a SL Raptor-style nozzle and calling it a day, in which case it would be impressive but not all that surprising if SpaceX is actually able to begin RVac testing before the end of 2019. Once a rough V1.0 engine is in place, the process of optimizing efficiency can be done slowly and methodically, all while exploiting an unprecedented wealth of data from flight and orbit-tested Raptor Vacuum engines.

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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 will resolve massive China recall with stickers and a software update

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tesla frozen door handle
Credit: YouTube | HMKARKI

Tesla will resolve its massive recall of nearly three million vehicles in China with stickers and a software update.

On Friday, Chinese regulators filed recall plans against Tesla, Xiaomi, Leapmotor, Xpeng, Chery, Geely, Dongfeng, Arcfox, and FAW to resolve what is essentially a carbon-copy issue throughout each of the companies’ vehicle models: emergency door release latches are simply not visible enough.

Tesla door handle saga gets its latest chapter and a big change is coming

The companies will be required to add things that will make these latches, which will open the door in the event of an emergency, more visible. Of the 7 million vehicles impacted, Tesla accounts for 2,975,910 units. More than 1.9 million of those are Model Y vehicles, with the rest, just over 970,000, being Model 3s.

To resolve the issue, Tesla is going to add warning labels to the emergency latches free of charge, and then utilize an Over-the-Air update to add a post-crash window-lowering strategy, according to CNEVpost.

This massive effort to fix the all-electric Model Y and Model 3’s emergency latch system comes just months after several probes across various markets identified the trouble some had identifying this latch. Those who had gotten involved in car accidents that stripped the vehicle of its power were not aware that every Tesla has emergency door latches.

China’s State Administration for Market Regulation (SAMR) said that severe crashes that disable a vehicle’s low-voltage system could not only hinder occupants from getting out, but also make it more difficult for emergency response workers to gain entry.

SAMR is starting to tighten the regulations it has on door handles on vehicles. A new mandatory national standard will take effect for all models starting January 1, 2027, and will require all doors to be equipped with mechanical release mechanisms. This will effectively end purely electronic door handles. Models already on sale with type approval have been granted a two-year transition period, which will enable things to change until January 2029.

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Tesla Semi is officially headed to Europe

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Credit: Tesla

Tesla has officially confirmed plans to bring its all-electric Semi truck to Europe, with full specifications and market-launch details set for unveiling at the IAA Transportation trade fair in Hannover, Germany.

The event runs September 15–20, with a possible press preview on September 14. The announcement, shared via Tesla’s Semi account, marks a significant expansion beyond North America nearly nine years after the truck’s original 2017 reveal.

In the United States, the Semi’s path has been gradual. Limited pilot production and customer deliveries began in late 2022, primarily to fleets such as PepsiCo. After years of refinement, high-volume manufacturing started on April 29, 2026, at a dedicated facility adjacent to Gigafactory Nevada.

The plant targets an annual capacity of 50,000 units, though the ramp is expected to be gradual, with “many thousands” of trucks projected by the end of 2026.

Demand is building, with recent orders including 500 units for Einride (deliveries starting September 2026, serving Amazon and others) and hundreds more from operators such as WattEV. Pricing stands at approximately $260,000 for the Standard Range and $290,000 for the Long Range before incentives.

Tesla Semi pricing revealed after company uncovers trim levels

Earlier in 2026, Tesla finalized production specifications that incorporated substantial updates. In February, the company detailed two variants designed for a full 82,000-pound gross combination weight.

The Standard Range offers about 325 miles of range with a 548 kWh battery and curb weight under 20,000 pounds. The Long Range delivers roughly 500 miles with an 822 kWh pack and a 23,000-pound curb weight. Both use three independent rear-axle motors producing up to 800 kW (about 1,073 horsepower), achieve energy consumption of around 1.7 kWh per mile, and support megawatt-class charging at up to 1.2 MW—recovering about 60 percent of range in 30 minutes through the MCS standard.

Additional refinements include a roughly 1,000-pound weight reduction versus earlier prototypes, improved aerodynamics, a 48-volt electrical architecture, electric power take-off up to 25 kW for refrigerated trailers, and fleet management software with over-the-air updates.

These advances position the Semi as a competitive option against diesel trucks on operating costs and performance. For Europe, adaptations such as lighting, cab configurations (including potential sleeper options), and regulatory compliance are anticipated.

With series production underway in Nevada and major fleet commitments secured, the upcoming IAA reveal will clarify timelines, European-specific specs, and pricing, potentially accelerating electrification of heavy-duty freight on both continents.

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Tesla Robotaxi gets a massive upgrade in Nevada

Nevada regulators just approved a massive expansion of Tesla’s robotaxi fleet across the entire county.

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Concept art of a Tesla Cybercab in Las Vegas Strip as rendered via Grok

Tesla’s robotaxi footprint in Nevada just grew by roughly 500 times in a single regulatory vote.

The Nevada Transportation Authority approved Tesla’s full Autonomous Vehicle Network Company permit on Thursday, clearing the way for the company to deploy up to 5,000 driverless vehicles across Clark County over the next 12 months. The decision came during a four hour general session meeting that Tesla investor Sawyer Merritt watched live and reported on X, noting the vote replaces the interim order that had limited Tesla to just 10 robotaxis on a narrow stretch of the Las Vegas Strip.

That earlier cap, covered here after it surfaced on August 13, came with restrictions that looked stricter than what Tesla runs in Austin: a 45 mph speed ceiling, no airport pickups, and a geofence confined to the Strip corridor. The new approval extends Tesla’s operating authority to all of Clark County, with room to request an even wider geofence across the state.

Tesla representatives at the meeting said they have no intention of putting 5,000 cars on the road right away. Commercial rides are expected to start within 30 days, pending vehicle inspections, insurance filings, and fare approval, the standard steps every robotaxi operator in Nevada has had to clear.

Tesla’s own Robotaxi account replied to the news with a short line, The golden future is upon us.

The timing lines up with Tesla’s broader robotaxi push this month. The company is preparing to open Cybercab rides to the public in Austin as soon as this month, and it opened a sweepstakes for riders to win a seat at the launch event. Tesla filed its original application for a 5,000 vehicle Nevada fleet back in June, a request regulators trimmed to 10 vehicles when they issued the interim order in July. Thursday’s vote effectively grants the number Tesla asked for from the start.

Zoox, the Amazon owned robotaxi operator, has run in Nevada since 2025 and was capped at 100 vehicles before Thursday’s decision. Tesla’s new ceiling puts it well ahead of that comparison on paper, though the company has said its actual fleet size will depend on how quickly FSD v15 rolls out, the software update executives have called the gateway to scaling unsupervised robotaxi operations nationwide.

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