News
Stoke Space to build SpaceX Raptor engine’s first real competitor
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.
The update that's rolling out to the fleet makes full use of the front and rear steering travel to minimize turning circle. In this case a reduction of 1.6 feet just over the air— Wes (@wmorrill3) April 16, 2024
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.
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.
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.
Investor's Corner
Mizuho keeps Tesla (TSLA) “Outperform” rating but lowers price target
As per the Mizuho analyst, upcoming changes to EV incentives in the U.S. and China could affect Tesla’s unit growth more than previously expected.
Mizuho analyst Vijay Rakesh lowered Tesla’s (NASDAQ:TSLA) price target to $475 from $485, citing potential 2026 EV subsidy cuts in the U.S. and China that could pressure deliveries. The firm maintained its Outperform rating for the electric vehicle maker, however.
As per the Mizuho analyst, upcoming changes to EV incentives in the U.S. and China could affect Tesla’s unit growth more than previously expected. The U.S. accounted for roughly 37% of Tesla’s third-quarter 2025 sales, while China represented about 34%, making both markets highly sensitive to policy shifts. Potential 50% cuts to Chinese subsidies and reduced U.S. incentives affected the firm’s outlook.
With those pressures factored in, the firm now expects Tesla to deliver 1.75 million vehicles in 2026 and 2 million in 2027, slightly below consensus estimates of 1.82 million and 2.15 million, respectively. The analyst was cautiously optimistic, as near-term pressure from subsidies is there, but the company’s long-term tech roadmap remains very compelling.
Despite the revised target, Mizuho remained optimistic on Tesla’s long-term technology roadmap. The firm highlighted three major growth drivers into 2027: the broader adoption of Full Self-Driving V14, the expansion of Tesla’s Robotaxi service, and the commercialization of Optimus, the company’s humanoid robot.
“We are lowering TSLA Ests/PT to $475 with Potential BEV headwinds in 2026E. We believe into 2026E, US (~37% of TSLA 3Q25 sales) EV subsidy cuts and China (34% of TSLA 3Q25 sales) potential 50% EV subsidy cuts could be a headwind to EV deliveries.
“We are now estimating TSLA deliveries for 2026/27E at 1.75M/2.00M (slightly below cons. 1.82M/2.15M). We see some LT drivers with FSD v14 adoption for autonomous, robotaxi launches, and humanoid robots into 2027 driving strength,” the analyst noted.
News
Tesla’s Elon Musk posts updated Robotaxi fleet ramp for Austin, TX
Musk posted his update on social media platform X.
Elon Musk says Tesla will “roughly double” its supervised Robotaxi fleet in Austin next month as riders report long wait times and limited availability across the pilot program in the Texas city. Musk posted his update on social media platform X.
The move comes as Waymo accelerates its U.S. expansion with its fully driverless freeway service, intensifying competition in autonomous mobility.
Tesla to increase Austin Robotaxi fleet size
Tesla’s Robotaxi service in Austin continues to operate under supervised conditions, requiring a safety monitor in the front seat even as the company seeks regulatory approval to begin testing without human oversight. The current fleet is estimated at about 30 vehicles, StockTwists noted, and Musk’s commitment to doubling that figure follows widespread rider complaints about limited access and “High Service Demand” notifications.
Influencers and early users of the Robotaxi service have observed repeated failures to secure a ride during peak times, highlighting a supply bottleneck in one of Tesla’s most visible autonomy pilots. The expansion aims to provide more consistent availability as the company scales and gathers more real-world driving data, an advantage analysts often cite as a differentiator versus rivals.
Broader rollout plans
Tesla’s Robotaxi service has so far only been rolled out to Austin and the Bay Area, though reports have indicated that the electric vehicle maker is putting in a lot of effort to expand the service to other cities across the United States. Waymo, the Robotaxi service’s biggest competitor, has ramped its service to areas like the San Francisco Bay Area, Los Angeles, and Phoenix.
Analysts continue to highlight Tesla’s long-term autonomy potential due to its global fleet size, vertically integrated design, and immense real-world data. ARK Invest has maintained that Tesla Robotaxis could represent up to 90% of the company’s enterprise value by 2029. BTIG analysts, on the other hand, added that upcoming Full Self-Driving upgrades will enhance reasoning, particularly parking decisions, while Tesla pushes toward expansions in Austin, the Bay Area, and potentially 8 to 10 metro regions by the end of 2025.
Tesla has finished construction at its biggest Supercharger ever in Lost Hills, California, and all 168 stalls are officially open as of today.
After several years of development, the company has officially announced that the Lost Hills Supercharger, known as Project Oasis, is officially open with 168 stalls active and available to drivers.
Tesla announced the completion of the Lost Hills Supercharger on Tuesday, showing off the site, which is powered by 10 Megapack batteries for storage and is completely independent of the grid, as it has 11 MW of solar panels bringing energy to the massive Battery Energy Storage System (BESS).
All 168 Stalls at the Tesla Supercharger in Lost Hills, California are officially open! pic.twitter.com/eo9xmZyUNB
— TESLARATI (@Teslarati) November 25, 2025
This is the largest Supercharger in the world and opens just in time for the Thanksgiving holiday, which is the most-traveled weekend of the year in the United States.
Spanning across 30 acres, it was partially opened back in July 2025 as Tesla opened just 84 of the 168 stalls at the site. However, Tesla finished certifying the site recently, which enabled the Supercharger to open up completely.
The site generates roughly 20 GWh of energy annually, which is enough to power roughly 1,700 homes. The launch of this site specifically is massive for the company as it plans to launch more Superchargers in more rural areas, making charging more available for cross-country rides that require stops in more remote regions of the United States.
This is perhaps the only weak point of Tesla’s massive charging infrastructure.
It has some features that are also extremely welcome for some owners, including things like pull-through stalls for those who tow, an idea that was extremely popular following the launch of the Cybertruck.
Tesla has over 70,000 active Superchargers across the world. The company has also made efforts to create unique experiences at some of the stops, most notably with its Tesla Diner, located on Santa Monica Boulevard in Los Angeles.
That Supercharger has two massive drive-in movie theaters and will soon transition to a full-service restaurant following the departure of its executive chef, Eric Greenspan.
Mizuho keeps Tesla (TSLA) “Outperform” rating but lowers price target
Tesla’s Elon Musk posts updated Robotaxi fleet ramp for Austin, TX
