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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 Model 3 hits quarter million miles with original battery and motor

The Model 3’s Battery Management System (BMS) shows a State of Health between 88% and 90%.

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(Credit: Tesla Asia/Twitter)

A Western Australian Tesla Model 3 has captured global attention after racking up an impressive 410,000 kilometers (254,000 miles) on its original battery and motor, while still retaining around 90% of its original battery health.

Long-term Model 3

The 2021 Model 3 Standard Plus, equipped with a 60 kWh lithium iron phosphate (LFP) battery, has been in constant use as an Uber rideshare vehicle. According to Port Kennedy EV specialist EV Workz, the car’s Battery Management System (BMS) shows a State of Health between 88% and 90%.

EV Workz owner Edi Gutmanis shared the findings on Facebook’s Electric Vehicles For Australia page on August 8, and the post quickly went viral. As per Gutmanis, the Model 3’s charging history shows 15,556 kWh delivered via DC fast charging (29% of the total) and 38,012 kWh via AC charging (71% of the total). 

Gutmanis also broke down the fuel savings for the Model 3. A petrol car covering the same 410,000 km at 7L/100km and $1.70 per liter would cost an estimated AU$50,000 in fuel. By comparison, charging the Tesla using average commercial rates would be about AU$20,737 and just AU$13,000 if using Western Australia’s EV tariff. That’s a potential refueling saving of roughly $37,000, not including the avoided maintenance costs of an internal combustion engine.

Simple fix

The car came into EV Workz for a driveline “judder” issue, as per a report form EV Central Australia. Gutmanis found the real cause was simply worn motor mount bushes. After seven hours of labor and $130 in parts, “the car drives just as good as the first day it left the dealership,” Gutmanis said.

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Gutmanis, whose business also performs EV conversions on classics and 4x4s, says the results aren’t surprising. “We expect this sort of longevity with EV batteries,” he explained, though this is the highest-mileage Model 3 he has encountered in Australia.

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Mysterious covered Tesla Model Y fleet spotted in Giga Berlin

The vehicles were sighted during a recent drone flyover of the Germany-based Model Y production site.

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Credit: @TobiasLindh/YouTube

A fleet of mysterious covered Model Y units has been spotted at the Giga Berlin complex. The vehicles were sighted during a recent drone flyover of the Germany-based Model Y production site.

A mysterious fleet

The mysterious Model Y fleet was sighted by longtime Giga Berlin watcher Tobias Lindh, who has been chronicling the progress and activities of Tesla’s German factory complex for years. During his flyover on August 12, 2025, Lindh noted that he was able to spot a fleet of fully covered Model Y units being gathered in one section of the Giga Berlin site.

The presence of the covered Model Y units caught a lot of attention online, with numerous Tesla watchers speculating if the vehicles were the Model Y L or the yet-to-be-released Model Y Performance. Giga Berlin only produces Model Y units, after all, and both the Model Y L and Model Y Performance are yet to be rolled out by the electric vehicle maker.

Tesla Model Y Performance the Model Y L

The Model Y is Tesla’s best-selling vehicle by a mile, selling so well that it was able to become the world’s best-selling car by volume in 2023. With the changeover to the new Model Y this year, Tesla has only released the vehicle’s updated RWD and AWD versions. The updated Model Y Performance is yet to be released as of writing, though sightings of apparent Model Y Performance units have been reported on social media.

In recent weeks, however, the Model Y news cycle has been dominated by the upcoming release of the Model Y L, an extended wheelbase, six-seat version of the best-selling all-electric crossover. The Model Y L is expected to be produced in Giga Shanghai initially, though Giga Berlin, the Fremont Factory, and Giga Texas are also expected to produce the variant in the near future. 

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Check out Giga Berlin’s mysterious Model Y fleet in the video below.

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Ukraine completes first Starlink direct-to-cell test in Eastern Europe

The trial was announced by the Ministry of Digital Transformation and Kyivstar’s parent company Veon, in a press release.

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Credit: SpaceX

Ukraine’s largest mobile operator, Kyivstar, has completed its first test of Starlink’s Direct to Cell satellite technology, enabling text messages to be sent directly from 4G smartphones without extra hardware. 

The trial was announced by the Ministry of Digital Transformation and Kyivstar’s parent company Veon in a press release.

First Eastern Europe field test

The Zhytomyr region hosted the pilot, where Deputy Prime Minister Mykhailo Fedorov and Kyivstar CEO Oleksandr Komarov exchanged texts and even made a brief video call via Starlink’s satellite link in northern Ukraine’s Zhytomyr region. 

Veon stated that the test marked Eastern Europe’s first field trial of the technology, which will allow Kyivstar’s 23 million subscribers to stay connected in areas without cellular coverage. The service will debut in fall 2025 with free text messaging during its testing phase.

“Our partnership with Starlink integrates terrestrial networks with satellite platforms, ensuring that nothing stands between our customers and connectivity – not power outages, deserts, mountains, floods, earthquakes, or even landmines,” Veon CEO Kaan Terzioglu stated.

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Starlink in Ukraine

Kyivstar signed its Direct to Cell agreement with Starlink in December 2024, about a year after a major cyberattack disrupted service and caused nearly $100 million in damages, as noted in a report from the Kyiv Independent. Starlink technology has been a pivotal part of Ukraine’s defense against Russia in the ongoing conflict.

“Despite all the challenges of wartime, we continue to develop innovative solutions, because reliable communication under any circumstances and in any location is one of our key priorities. Therefore, this Kyivstar project is an example of effective partnership between the state, business, and technology companies, which opens the way to the future of communication without borders,” Mykhailo Fedorov, First Deputy Prime Minister of Ukraine, said.

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