Connect with us

News

Stoke Space to build SpaceX Raptor engine’s first real competitor

Stoke Space has begun testing parts of an engine similar to SpaceX's famous Raptor.

Published

on

Seattle startup Stoke Space has revealed plans to develop an efficient rocket engine similar to the Raptors that power SpaceX’s Starship.

Formed in October 2019, Stoke Space secured its first significant round of funding – $9.1 million – less than three years ago. At that time, CEO and co-founder Andy Lapsa says that the startup had just five employees, no permanent workspace, and a “barren field” for a test site. Within 18 months, Stoke Space had turned that empty field into an impressive test facility, conducted numerous component tests, and assembled its first full-scale rocket engine – an exotic UFO-like device unlike any seen before.

It also raised another $65 million – enough funding to begin earnestly developing a potentially revolutionary rocket capable of launching more than 1.65 tons (~3600 lb) into orbit for less than half a million dollars. To realize that extremely ambitious goal, Stoke Space has taken the even more ambitious step of attempting to make the first rocket it develops fully reusable. Simultaneously, the company has incorporated several exotic technologies into that rocket, recently culminating in a surprise announcement that it will attempt to develop one of the most difficult types of engines to power that rocket’s booster stage.

Full-flow staged combustion

At the end of an extended interview and tour with YouTuber Tim Dodd (The Everyday Astronaut), CEO Andy Lapsa revealed that Stoke Space has decided to build a full-flow staged combustion (FFSC) engine for the first stage of its reusable rocket. FFSC is the most efficient type of combustion cycle available for a chemical bipropellant rocket engine, but it’s also the most difficult to develop.

Advertisement

A full-flow engine attempts to squeeze every possible ounce of performance out of the propellant it consumes. The most powerful and efficient chemical rocket engines must consume huge volumes of propellant in a short amount of time without destroying the launch vehicle they’re attached to. To create pressure and spin the pumps that are needed to feed that propellant into their main combustion chamber, engines often burn a small amount of propellant in a separate gas generator or preburner. Gas-generator engines vent that exhaust overboard, reducing efficiency but making for a much simpler design. Staged-combustion engines use preburners to create gas that pumps liquid propellant, and that exhaust gas is eventually injected into the main combustion chamber.

Full-flow staged combustion sets itself apart by having two separate pumps and preburners for oxidizer and fuel. Unlike simpler variants of staged combustion, FFSC engines turn all of their propellant into gas before injecting it into the combustion chamber. That hot gas increases the heat of combustion and the pressure inside the combustion chamber, ensuring that virtually all of the propellant that flows through the engine is combusted and turned into thrust as efficiently as possible. FFSC is exceptionally difficult because of the extra-high temperatures and pressures it requires, as well as the need for an oxygen-rich preburner and pump. In a high-pressure, hot-oxygen environment, virtually anything imaginable – including most metals – will spontaneously combust.

Only complex custom-designed alloys can survive those conditions. SpaceX’s Raptor, the only FFSC engine that has ever flown, is especially difficult because it’s meant to be highly reusable. To be successful, Raptor will have to survive those conditions dozens or even hundreds of times in a row with little to no maintenance in between.

The first booster engine Stoke Space ever attempts to build will be a reusable full-flow staged combustion engine powered by liquid methane and liquid oxygen – essentially a smaller version of SpaceX’s Raptor. Stoke’s booster is otherwise familiar and features deployable landing legs like SpaceX’s Falcon boosters. Lapsa says it will likely also have grid fins.

Reusing the upper stage

In some ways, the upper stage of Stoke’s first rocket is even more ambitious. Powered by hydrogen and oxygen propellant, Stoke has designed a conical capsule-like upper stage with an integral fairing. The upper stage’s propulsion is exotic and unique. A large pump will feed propellant to up to 30 combustion chambers distributed around the rim of its heat shield. The exhaust coming from those 30 chambers will expand and partially push against the upper stage’s equally exotic metallic, liquid-cooled heat shield. That expansion against the heat shield improves the efficiency of the upper stage and means that its engine will technically be an aerospike.

Advertisement

Stoke has already begun testing a full-scale version of the upper stage’s UFO-like rocket engine with 15 combustion chambers. Since testing began in the second half of 2022, Stoke has completed dozens of static fires. Everyday Astronaut’s tour also revealed that the startup has made significant progress fabricating and assembling its first full-scale upper stage prototype – tanks, nosecone, heat shield, engine, and all.

Reminiscent of SpaceX’s Grasshopper and Starhopper campaigns, Stoke plans to conduct hop tests with that prototype if it makes it through qualification testing. On February 7th, Stoke also revealed that it’s begun testing a crucial component of its full-flow booster engine. All told, Stoke Space is making progress at a remarkable pace and continues to tackle the hardest problems. The startup has also avoided widely publicizing any specific deadlines, instead choosing to let hardware and tangible results speak for themselves. Only time will tell if that approach pays off, but Stoke is off to an exceptionally impressive start in an industry full of impressive rocket startups.

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

Elon Musk clarifies viral Tesla Cybertruck accident with driver logs

Musk has come out to say that the driver logs have already shown that the driver “disengaged Autopilot four seconds before crashing,” in a post on X.

Published

on

Credit: Fox Business | Hilliard Law Firm

Tesla CEO Elon Musk has clarified some details regarding the viral Tesla Cybertruck accident with company driver logs, which show various metrics at the time of an incident.

The logs have been used in the past to pull responsibility off of Tesla when the automaker’s Full Self-Driving (Supervised) or Autopilot platforms are blamed for a collision or accident. It appears this will be no different.

On Tuesday, a video of a Cybertruck crashing into an overpass barrier in August 2025 was shared by Fox Business in a story that reported a woman was suing the automaker for $1 million in a liability and negligence case.

In the suit, Justine Saint Amour said that, “Something terrifying happened, without warning, the vehicle attempted to drive straight off an overpass.” Her attorney, Bob Hilliard, said Amour “tried to take control, but crashed into the barrier and was seriously injured (mostly her shoulder, neck, and back).”

The Tesla Model Y is leading China’s electric SUV segment by a wide margin

Tesla vehicle crashes are widely popular to report by mainstream media outlets because of the sensationalism of the event. Oftentimes, these outlets will include Tesla in the headline, especially because it will pique the interest of the masses, as most who read the story are waiting to see the claim that Autopilot or Full Self-Driving was the culprit of the accident.

However, Tesla has access to the logs of every vehicle in its fleet, which will show the various metrics, like whether either FSD or Autopilot was active, if the accelerator was pressed, the speed, and other important factors.

Musk has come out to say that the driver logs have already shown that the driver “disengaged Autopilot four seconds before crashing,” in a post on X.

If the logs do show this, which Tesla will likely have to prove in court, the real question would be why did the Amour disengage the suite?

Tesla’s Full Self-Driving suite is still not fully autonomous, meaning the driver cannot pull attention away from the road and must be ready to take over the vehicle at all times.

It will be interesting to see how this particular case pans out, especially considering the clip that was released by the law firm starts at about four seconds before the collision. Tesla logs have dispelled media reports in the past that have accused the company’s suite of being responsible for an accident, so there will be some major attention on what is proven in this particular case.

Continue Reading

News

Tesla Robotaxi appears to be heading to a new U.S. city

Things are expanding for Robotaxi, but the big sign that it is really moving along greatly will be with the expansion to a new city. Tesla has not gone outside of Austin or the Bay Area as of yet, and launching in a new city will be a great indicator of progress.

Published

on

Credit: Tesla

Tesla Robotaxi appears to be heading to a new U.S. city, and although the company has revealed plans to launch in six new metros this year, it has yet to establish a new location outside of Austin and the Bay Area of California, where it has operated since last Summer.

A lot full of Model Y vehicles was spotted in Henderson, a town just north of Las Vegas, but there seems to be more than just this hint indicating that the Sin City will be the next location to offer potentially driverless rides in a Tesla using its Full Self-Driving suite.

These Model Ys are not your typical vehicles, as they are fitted with hardware that is only on Robotaxis: a rear camera washer is the dead giveaway:

The photos and video of the lot were taken by TheZacher on X, who spotted the Model Y fleet in the Henderson parking lot.

The rear camera washer is the main piece of evidence here that indicates Tesla could be looking to expand Robotaxi to Las Vegas, a major ride-hailing hot spot, as it is one of the biggest tourist attractions in the United States. Ride-sharing is a major industry in Vegas, especially for those who are staying off the Strip.

Tesla has also been extremely transparent that Vegas is on its radar for the Robotaxi fleet, as it revealed last year that it was one of five new U.S. cities that it planned to launch the ride-hailing service in this year.

Tesla confirms Robotaxi is heading to five new cities in the U.S.

The others were Phoenix, Dallas, Houston, and Miami.

Things are expanding for Robotaxi, but the big sign that it is really moving along greatly will be with the expansion to a new city. Tesla has not gone outside of Austin or the Bay Area as of yet, and launching in a new city will be a great indicator of progress.

It will also give Tesla a new benchmark against rival company Waymo, which has operated in Las Vegas for some time.

Continue Reading

News

Tesla Roadster gets new unveiling date once again

Musk announced last year that the unveiling, which initially happened back in 2018, would take place on April Fool’s Day. Initial deliveries at the 2018 event were slotted for 2020, but delays in the project, as well as prioritization of other things, continued to push the Roadster back.

Published

on

A red Tesla Roadster driving around a turn
(Credit: Tesla)

The Tesla Roadster is perhaps the most anticipated vehicle in the company’s history, but those who have been waiting anxiously for it will have to push their timelines back once again.

Tesla CEO Elon Musk has revealed that the company is once again pushing back the unveiling event that was originally planned for April 1. It will now take place “probably in late April.”

Musk announced last year that the unveiling, which initially happened back in 2018, would take place on April Fool’s Day. Initial deliveries at the 2018 event were slotted for 2020, but delays in the project, as well as prioritization of other things, continued to push the Roadster back.

There has been so much hype about the Roadster that people are right to be excited about the prospect of its existence.

Musk’s most recent rumblings about the vehicle came last Fall, when he appeared on the Joe Rogan Experience podcast, where he once again hinted the car would be able to hover for a short period.

He said:

Whether it’s good or bad, it will be unforgettable. My friend Peter Thiel once reflected that the future was supposed to have flying cars, but we don’t have flying cars. I think if Peter wants a flying car, he should be able to buy one…I think it has a shot at being the most memorable product unveiling ever. [It will be unveiled] hopefully before the end of the year. You know, we need to make sure that it works. This is some crazy technology in this car. Let’s just put it this way: if you took all the James Bond cars and combined them, it’s crazier than that.”

Additionally, he said the vehicle would not be something that would prioritize safety. Musk said that “If safety is your number one goal, do not buy the Roadster.” It’s made for speed and excitement, not for grocery-getting.

Elon Musk just said some crazy stuff about the Tesla Roadster

As the April 1 unveiling event that was originally planned was nearing without any communication to fans, media, or anyone who would potentially be in attendance, it seemed to be pretty obvious that Tesla was not ready to pull the trigger on the event quite yet.

There could be some last-minute things to finalize, or it could be something else. One thing is for certain, though: we are not super surprised that things were moved back.

Tesla has definitely been putting some things in motion for the Roadster. A few months back, Tesla started to ramp up hiring for the Roadster, and earlier in March, it submitted a patent application for a new seat design.

Continue Reading