Connect with us

News

SpaceX’s first orbital Starship engine just breathed fire

Published

5 years ago

on

Less than three weeks after shipping to Texas, SpaceX says that Starship’s first Raptor Vacuum engine has completed a “full duration test fire” on the march towards orbital test flights.

Known as Raptor Vacuum or RVac, the engine is almost entirely based off of its sea level-optimized cousin, taking all of the complex turbomachinery and combustion chambers that represent the bulk of a rocket engine. Things start to diverge below the throat of the combustion chamber (the narrow part of the central hourglass-like curve), where SpaceX has expanded Raptor’s existing bell nozzle by a factor of five or more.

SpaceX’s reusable Starship spacecraft will use a mix of three sea level Raptors and three Raptor Vacuum engines to give it the thrust it needs to reach orbit and ensure efficient operations both in atmosphere and vacuum.

Raptor Vacuum (roughly) to scale alongside Raptor Sea Level, a Space Shuttle Main Engine (SSME), and a Saturn V F-1. (Teslarati)

In simple terms, a rocket engine can benefit from a vacuum-optimized nozzle because the added surface area (more or less) gives the extremely high-pressure gases exiting its combustion chamber even more footholds to push against. Rocket nozzles are at their most efficient when the engine’s exhaust gas finishes expanding to match ambient pressure at the exact moment it exits the bell. Logically, at sea level on Earth, the ambient air pressure is quite high, meaning that rocket exhaust doesn’t have to expand as much to equalize.

In the vacuum of space, however, exhaust gases must expand far more to reach the same pressure as its surroundings. For rocket propulsion, that extra expansion can be exploited to make a more efficient engine, squeezing extra energy out of the same propellant and in a perfect vacuum, the most efficient nozzle would technically be infinite. Engineering and physical infinities don’t exactly get along, unfortunately, so vacuum rocket engineers are forced to settle on a nozzle size at a scale that humans can feasibly manufacture.

In theory, Starship doesn’t need Raptor Vacuum engines to be a functioning orbital spacecraft and CEO Elon Musk himself floated a design with seven sea-level engines just two years ago. Since then, the SpaceX CEO revealed that Raptor was making such good progress that the company undid the removal of vacuum-optimized engines from Starship’s baseline design.

Look, Ma, no vacuum engines! (SpaceX)

It’s unclear exactly what SpaceX means when it says that Raptor Vacuum SN1 completed a “full duration test fire.” For Starship, a full-duration orbital insertion burn – beginning immediately after Super Heavy booster separate – would likely be no shorter than five or six minutes. Even for SpaceX, going from shipping the very first engine (Raptor Vacuum) produced to a successful several-minute static fire in less than three weeks’ time would be an almost inconceivable feat of engineering. The feat would imply that SpaceX is already extremely comfortable with several-minute Raptor burns – perhaps the single biggest hurdle standing between Starship and orbit.

More likely, “full duration test fire” simply refers to the fact that the pathfinder Raptor Vacuum engine managed to ignite, burn, and shut down on schedule – avoiding a premature shutdown, in other words. For an engine as large and complex as Raptor, even that downgraded interpretation would represent an impressive achievement.

Advertisement

Check out Teslarati’s Marketplace! We offer Tesla accessories, including for the Tesla Cybertruck and Tesla Model 3.

Related Topics:

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.

Advertisement
Comments

Cybertruck

FIRST LOOK: Tesla Cybertruck police cruiser interior

The LVMPD released a new video of the police cruisers that were donated by billionaires Ben and Felicia Horowitz.

Published

59 minutes ago

on

October 29, 2025

By

Credit: LVMPD | X

The first look at the Tesla Cybertruck police cruisers for the Las Vegas Metro Police Department has been going around as the city begins to add them to its active fleet.

The LVMPD released a new video of the police cruisers that were donated by billionaires Ben and Felicia Horowitz, showing their design, as well as the first look at the front of the vehicle where police will sit, as well as the back where the criminals will think about their actions.

Sheriff Kevin McMahill commented on the addition of the Cybertrucks to the fleet, which includes recognition of their symbolism regarding the mission of the Department itself:

“These represent something bigger than a police vehicle. They represent innovation and our continued commitment to serve this community with the best tools available — safely, efficiently, and responsibly. They can handle everything from Fremont Street to Red Rock Canyon.”

The LVMPD had the Cybertrucks primed for law enforcement use by Upfit Tesla, a division of Unplugged Performance, the unequivocal leader in performance upgrades for Teslas.

The first look at the interior of the police cruisers is awesome to see, especially as it shows the Cybertruck’s ability to cater to every and any application for personal or professional use.

The front of the Cybertruck police vehicle shows an interior fully outfitted for a shift in Las Vegas. A laptop is mounted next to the center touchscreen, and siren and light controls are located in the center for easy access for officers:

The rear of the cruiser is plain and fitted with plastic seats, typical for the transportation of criminals and suspects, as well as a partition that appears to be made of ballistic glass, helping to protect officers from those they have arrested. It is also reinforced with steel and foam lines the top of the partition:

The fleet was donated shortly after a Cybertruck exploded at the front entrance of Trump Tower in Las Vegas in January. While the person inside lost their life, the Cybertruck’s ability to muffle most of the blast and keep damage relatively limited to the building impressed many.

Continue Reading

News

Tesla Cybercab spotted testing on public roads for the first time

The car was spotted just minutes from Tesla’s Engineering Headquarters in Los Altos, California. There are a few interesting tidbits we can gather from the photo and the information shared with it.

Published

9 hours ago

on

October 29, 2025

By

Credit: Teslarati

The Tesla Cybercab has been spotted testing on public roads for the first time, marking a substantial step forward in the vehicle’s development.

The car was spotted just minutes from Tesla’s Engineering Headquarters in Los Altos, California. There are a few interesting tidbits we can gather from the photo and the information shared with it:

The vehicle had a driver and side view mirrors equipped on it, which seems to be pretty expected, especially at this stage.

Tesla might have been using its Full Self-Driving software with the vehicle as it enters this new stage of testing on public roads. This seems most likely, especially as the car, which has long been developed to be void of a steering wheel and pedals, will totally rely on autonomous tech to transport one or two passengers to their destination.

Additionally, side view mirrors are required by law at delivery, and Tesla was likely looking to keep things as safe and elementary as possible, especially with this early stage of testing.

As this is the first time the vehicle has been spotted on public roads and the first time it was likely testing on them, Tesla was being cautious.

There have been a lot of developments with Cybercab over the past few weeks, as the car has been spotted testing on the Fremont Factory’s test track, units have been seen outside of Gigafactory Texas’s crash testing facility, and there has been some additional speculation about what the vehicle’s standard equipment will be.

There have also been quite a few job postings by Tesla for manufacturing and production roles related to Cybercab over the past few weeks.

Yesterday, Tesla’s Board Chair, Robyn Denholm, revealed that the company could end up building Cybercab with a steering wheel and pedals, contrary to what Tesla and CEO Elon Musk have wanted to do.

Tesla Cybercab might be getting a huge change

The vehicle has yet to reach that stage of regulatory testing, but Tesla wants to start volume production in Q2. If it wants to release the vehicle without any manual controls, that means that Full Self-Driving will need to be completed within the next eight months.

Continue Reading

News

Tesla hints it could see ‘a few more vehicles’ released soon

Denholm said on CNBC yesterday that “we do have a few other vehicles coming out.”

Published

12 hours ago

on

October 29, 2025

By

Tesla Board Chair Robyn Denholm hinted the company could see “a few more vehicles” coming out and being released soon, although there is no indication of what could be on the way based on her comments.

However, Tesla has hinted toward several potential releases in the coming years, as other executives, including Chief Designer Franz von Holzhausen, have talked briefly about what could be on the way.

Denholm said on CNBC yesterday that “we do have a few other vehicles coming out.”

It was a vague and almost cryptic sentence, as, in all honesty, it was not completely clear whether she was talking about recent releases that are just making their way to market, like the Model 3 and Model Y “Standard,” or new vehicles altogether.

Nevertheless, it’s worth dissecting.

Tesla “Standard” Models

On October 7, Tesla launched the Standard Model 3 and Model Y, stripped-down versions of their now “Premium” siblings. The Standard trims lack premium features like leather seats, a rear touchscreen, and a glass roof, among other features.

Tesla begins deliveries of its affordable Model Y Standard

These cars are just starting to be delivered for the first time, so it is possible that Denholm was referring to these cars.

Potential Model 2 Hint?

There has always been a looming vehicle model that many Tesla fans and owners have been intrigued by: the Model 2.

This car was hinted at being the $25,000 model that Tesla was rumored to be developing, and many thought that was the vehicle that would be released earlier this month, not the Standard Model 3 and Model Y.

Instead, the Model 2 could be something that would enable Tesla to reach an entirely new consumer base, including those who are not able to swing the payment for the company’s more premium offerings.

It seems Tesla will have to launch some sort of extremely affordable model in the future, and with the Cybercab being slotted at that rough price point, it would not be out of the question for it to be in the realm of possibility for future releases.

It’s worth noting, however, that it is probably unlikely this will happen. Tesla is so deadset focused on autonomy, it seems Cybercab would take extreme precedence over the unconfirmed “Model 2.”

Cybertruck-inspired SUV

Tesla fans have been begging the company to develop a full-size SUV that would compete with the Ford Expedition or Chevrolet Tahoe, but the company has not given any indication that this would be something it would build.

Nevertheless, there was a very subtle hint in a recent promotional clip that showed a Cyber SUV mock-up placed strategically next to a clay model of a Model 3:

Tesla appears to be mulling a Cyber SUV design

The Model X is simply not what people want when it comes to an SUV, as it does not have the seating capacity and cargo space that many need with a full-sized SUV.

This issue, in particular, has been one that has been extremely relevant to the company’s future lineup as consumers have shown they would be interested in a Tesla vehicle that fit this description.

Additionally, von Holzhausen said in September that a Cyber SUV or a smaller electric pickup with a more traditional design is “definitely things we’ve considered…We’re working on so many innovative and fun things.”

Tesla gives big hint that it will build Cyber SUV, smaller Cybertruck

Continue Reading

Trending