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SpaceX sends “radically redesigned” Starship engine to Texas for hot-fire tests

As of September 2017, subscale Raptor engines had been cumulatively fired for more than 1200 seconds in just 12 months of testing. (SpaceX)

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SpaceX has shipped one of the first of a group of Starship engines known as Raptor, described last month by CEO Elon Musk as “radically redesigned”. A culmination of more than 24 months of prototype testing, the first flight-worthy Raptor could be ignited for the first time as early as February.

According to Musk, three of these redesigned Raptors will power the first full-scale BFR prototype, a Starship (upper stage) test article meant to conduct relatively low-altitude, low-velocity hop tests over the southern tip of Texas. Those tests could also begin next month, although a debut sometime in March or April is increasingly likely.

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Effectively designed on a blank slate, Raptor began full-scale component-level tests in 2014 at NASA’s Mississippi-based Stennis Space Center, evolving from main injector development to oxygen preburner hot-fires in 2015. Soon after Raptor’s prototype preburner design was validated at Stennis, SpaceX moved testing to its privately-owned and operated facilities in McGregor, Texas, where Raptor static fire testing has remained since.

Just days before CEO Elon Musk was scheduled to reveal SpaceX’s next-generation rocket (BFR, formerly known as the Interplanetary Transport System or ITS) in September 2016, he announced in a tweet that propulsion engineers and technicians had successful hot-fired an integrated Raptor prototype – albeit subscale – for the first time ever. Just 12 months later, Musk once again took to the stage to announce an update to BFR’s design, while also revealing that prototype Raptor engines had already completed more than 1200 seconds (20 minutes) of cumulative hot-fire tests, an extremely aggressive and encouraging rate of progress for such a new engine.

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Although Raptor undoubtedly borrows heavily from much of the same expertise that designed Merlin 1 and operated and improved it for years, that is roughly where the similarities between Raptor and M1D end. M1D, powered by refined kerosene (RP-1) and liquid oxygen, uses a combustion cycle (gas-generator) that is relatively simple and reliable at the cost of engine efficiency, although SpaceX propulsion expertise still managed to give M1D the highest thrust-to-weight ratio of any liquid rocket engine ever flown. Still, measured by ISP (instantaneous specific impulse), M1D’s inefficient kerolox gas-generator cycle ultimately means that the engine simply can’t compete with the performance of engines with more efficient propellants and combustion cycles.

While SpaceX’s Falcon 9 and Heavy rockets – powered by Merlin 1D and Merlin Vacuum – are more than adequate in and around Earth orbit, a far more efficient engine was needed for the company to enable the sort of interplanetary colonization Musk had in mind when he created SpaceX. Raptor was the answer. Ultimately settling on liquid methane and oxygen (methalox) as the propellant and a full-flow staged-combustion (FFSC) cycle, Raptor was designed to be extraordinarily reliable and efficient in order to safely power a spacecraft (BFS/Starship) meant to ferry dozens or hundreds of people to and from Mars.

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An excellent NASASpaceflight article explores the engine’s journey from a blank sheet to integrated static-fire tests and offers a deeper explanation of the technical details.

Raptor enters a new era

For all the extensive and invaluable testing SpaceX has done with a series of prototype Raptor engines, the engines tested were subscale versions with around 30% the thrust of the c. 2016 Raptor and around 40-50% of the updated c. 2017 iteration, producing almost the same amount of thrust as Merlin 1D (914 kN to Raptor’s ~1000 kN). In September 2018, Musk described Raptor as an “approximately…200-ton (~2000 kN) thrust engine” that would eventually operate with a chamber pressure as high as 300 bar (an extraordinary ~4400 psi), requiring at least one of the FFSC engine’s two preburners (used to power separate turbopumps) to operate at a truly terrifying ~810 bar (nearly 12,000 psi).

Conveniently stood beside a Merlin 1D engine also ready for hot-fire acceptance testing, the Raptor engine spotted departing SpaceX’s Hawthorne, CA factory last week was reportedly immense in person, towering over an M1D engine. Raptor also featured a mass of spaghetti-like plumbing (complexity necessary for its advanced combustion cycle), with a significant fraction of the metallic pipes and tubes displaying mirror-like finishes. Most notable was an obvious secondary preburner/turbopump stack and the lack of any exhaust port, whereas M1D relies on a single turbopump and exhausts the gases used to power it. Raptor’s full-flow staged-combustion cycle uses separate oxygen and methane preburners to power separate turbopumps, significantly improving mass flow rate and smoothing out combustion mixing.

 

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Unlike all previous hot-fired Raptors, those shipping now to McGregor, Texas are expected to be the first completed engines with a finalized design, arrived at only after a period of extensive testing and iterative improvement. They also appear to be full-scale, meaning that the test bays dedicated to Raptor will likely need to be upgraded (if they haven’t been already) to support a two- or threefold increase in maximum thrust.

SpaceX’s Starship hopper will need three finalized engines, meaning that the Raptor now in McGregor, Texas may not have been the first to arrive. Nevertheless, the shipment of full-scale hardware is always an extremely encouraging milestone for any advanced technology development program, while also foreshadowing the first imminent static-fires of the “radcally redesigned” rocket engine. With hardware now at the test site before January is out, a February test debut – one month behind a January debut teased by Elon Musk last December – is not out of the question.

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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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SpaceX and xAI tapped by Pentagon for autonomous drone contest

The six-month competition was launched in January and is said to carry a $100 million award.

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Credit: SpaceX/X

SpaceX and its AI subsidiary xAI are reportedly competing in a new Pentagon prize challenge focused on autonomous drone swarming technology, as per a report from Bloomberg News

The six-month competition was launched in January and is said to carry a $100 million award.

Bloomberg reported that SpaceX and xAI are among a select group invited to participate in the Defense Department’s effort to develop advanced drone swarming capabilities. The goal is reportedly to create systems that can translate voice commands into digital instructions and manage fleets of autonomous drones.

Neither SpaceX, xAI, nor the Pentagon’s Defense Innovation Unit has commented on the report, and Reuters said it could not independently verify the details.

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The development follows SpaceX’s recent acquisition of xAI, which pushed the valuation of the combined companies to an impressive $1.25 trillion. The reported competition comes as SpaceX prepares for a potential initial public offering later this year.

The Pentagon has been moving to speed up drone deployment and expand domestic manufacturing capacity, while also seeking tools to counter unauthorized drone activity around airports and major public events. Large-scale gatherings scheduled this year, including the FIFA World Cup and America250 celebrations, have heightened focus on aerial security.

The reported challenge aligns with broader Defense Department investments in artificial intelligence. Last year, OpenAI, Google, Anthropic, and xAI secured Pentagon contracts worth up to $200 million each to advance AI capabilities across defense applications.

Elon Musk previously joined AI and robotics researchers in signing a 2015 open letter calling for a ban on offensive autonomous weapons. In recent years, however, Musk has spoken on X about the strengths of drone technologies in combat situations.

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Doug DeMuro names Tesla Model S the Most Important Car of the last 30 years

In a recent video, the noted reviewer stated that the choice was “not even a question.”

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Popular automotive reviewer and YouTuber Doug DeMuro has named the 2012 Tesla Model S as the most important car of the last 30 years.

In a recent video, the noted reviewer stated that the choice was “not even a question,” arguing that the Model S did more to change the trajectory of the auto industry than any other vehicle released since the mid-1990s.

“Unquestionably in my mind, the number one most important car of the last 30 years… it’s not even a question,” DeMuro said. “The 2012 Tesla Model S. There is no doubt that that is the most important car of the last 30 years.”

DeMuro acknowledged that electric vehicle adoption has faced recent headwinds. Still, he maintained that long-term electrification is inevitable.

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“If you’re a rational person who’s truthful with yourself, you know that the future is electric… whether it’s 10, 20, 30 years, the future will be electric, and it was the Model S that was the very first car that did that truthfully,” he said.

While earlier EVs like the Nissan Leaf and Chevrolet Volt arrived before the Model S, DeMuro argued that they did not fundamentally shift public perception. The Model S proved that EVs “could be cool, could be fast, could be luxurious, could be for enthusiasts.” It showed that buyers did not have to make major compromises to drive electric.

He also described the Model S as a cultural turning point. Tesla became more than a car company. The brand expanded into Superchargers, home energy products, and a broader tech identity.

DeMuro noted that the Leaf and Volt “made a huge splash and taught us that it was possible.” However, he drew a distinction between being first and bringing a technology into the mainstream.

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“It’s rarely about the car that does it first. It’s about the car that brings it into the mainstream,” he said. “The Model S was the car that actually won the game even though the Leaf and Volt scored the first.”

He added that perhaps the Model S’ most surprising achievement was proving that a new American automaker could succeed. For decades, industry observers believed the infrastructure and capital requirements made that nearly impossible.

“For decades, it was generally agreed that there would never be another competitive American car company because the infrastructure and the investment required to start up another American car company as just too challenging… It was just a given basically that you couldn’t do it. And not only did they go it, but they created a cultural icon… That car just truly changed the world,” he said. 

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Elon Musk doubles down on Tesla Cybercab timeline once again

“Cybercab, which has no pedals or steering wheel, starts production in April,” Musk said.

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Credit: @JT59052914/X

CEO Elon Musk doubled down once again on the timeline of production for the Tesla Cybercab, marking yet another example of the confidence he has in the company’s ability to meet the aggressive timeline for the vehicle.

It is the third time in the past six months that Musk has explicitly stated Cybercab will enter production in April 2026.

On Monday morning, Musk reiterated that Cybercab will enter its initial manufacturing phase in April, and that it would not have any pedals or a steering wheel, two things that have been speculated as potential elements of the vehicle, if needed.

Musk has been known to be aggressive with timelines, and some products have been teased for years and years before they finally come to fruition.

One of perhaps the biggest complaints about Musk is the fact that Tesla does not normally reach the deadlines that are set: the Roadster, Semi, and Unsupervised Full Self-Driving suite are a few of those that have been given “end of this year” timelines, but have not been fulfilled.

Nevertheless, many are able to look past this as part of the process. New technology takes time to develop, but we’d rather not hear about when, and just the progress itself.

However, the Cybercab is a bit different. Musk has said three times in the past six months that Cybercab will be built in April, and this is something that is sort of out of the ordinary for him.

In December 2025, he said that Tesla was “testing the production system” of the vehicle and that “real production ramp starts in April.

Elon Musk shares incredible detail about Tesla Cybercab efficiency

On January 23, he said that “Cybercab production starts in April.” He did the same on February 16, marking yet another occasion that Musk has his sights set on April for initial production of the vehicle.

Musk has also tempered expectations for the Cybercab’s initial production phase. In January, he noted that Cybercab would be subjected to the S-curve-type production speed:

“…initial production is always very slow and follows an S-curve. The speed of production ramp is inversely proportionate to how many new parts and steps there are. For Cybercab and Optimus, almost everything is new, so the early production rate will be agonizingly slow, but eventually end up being insanely fast.”

Cybercab will be a huge part of Tesla’s autonomous ride-sharing plans moving forward.

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