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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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Elon Musk’s $10 Trillion robot: Inside Tesla’s push to mass produce Optimus

Tesla’s surging Optimus job listings reveal a company sprinting from prototype to one million robot production.

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Tesla is accelerating its push to bring the Optimus humanoid robot to high volume production, and its recent job listings tells the story as clearly as any earnings call.

With well over 100 Optimus related job openings now posted across its U.S. facilities, Tesla is signaling a critical pivot for the program, moving it from a captivating tech demo to a serious manufacturing endeavor. Roles span the full spectrum of the product lifecycle, from Robotics Software Engineers and Manufacturing Engineers to Mechanical Integration Engineers and AI Engineers focused on world modeling and video generation. One active listing for a Software Engineer on the Optimus team asks candidates to build scalable and reliable data pipelines for Optimus manufacturing lines and develop automation tools that accelerate analysis and visualization for mass manufacturing.

Tesla is racing toward a one million unit annual production target. The clearest signal yet that Tesla is treating Optimus as its primary business came on January 28, 2026, during the company’s Q4 2025 earnings call. Musk announced that Tesla is ending production of the Model S and Model X, and will repurpose those lines at its Fremont, California factory to build Optimus humanoid robots.

A production intent prototype of Optimus Version 3 is planned to be ready in early 2026, after which Tesla intends to build a one million unit production line with a targeted production start by the end of 2026. To support that ramp, Tesla broke ground on a massive new Optimus manufacturing facility at Gigafactory Texas in late 2025, with ambitions to eventually reach 10 million units per year.

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Tesla Giga Texas to feature massive Optimus V4 production line

The business case for scaling this aggressively is rooted in labor economics. Musk has stated that “Optimus has the potential to be the biggest product of all time,” reasoning that if Tesla can produce capable humanoid robots at scale and reasonable cost, every task currently performed by human labor becomes a potential application. In a separate statement, Musk framed Optimus’s long term importance even more bluntly, saying it could surpass Tesla’s vehicle business in scale with the potential to generate $10 trillion in revenue.

The industries Tesla is targeting first are those most burdened by repetitive physical labor. Early applications include manufacturing assembly, material handling and quality inspection, as well as logistics tasks like loading, unloading, sorting, and transporting goods in warehouses and distribution centers. Longer term, Tesla’s vision is for Optimus to penetrate household, medical, and logistics scenarios at the scale of a smartphone rollout.

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Tesla officially begins sunset of Model S and Model X

In the latest move to show Tesla is planning to eliminate the Model S and Model X from production, the company’s Korean arm has officially set a firm cutoff date of March 31, 2026, for new orders of both models.

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Credit: Tesla

Tesla has officially started its process of sunsetting the Model S and Model X just months after the company confirmed it would stop producing the two flagship vehicles in 2026.

This step marks the end of an era for the vehicles that helped establish not only Tesla’s prowess as an automaker but also its status as a disruptor in the entire car industry. While these two cars have done a tremendous amount for Tesla, the signal that it is time to wind down their production has evidently arrived.

In the latest move to show Tesla is planning to eliminate the Model S and Model X from production, the company’s Korean arm has officially set a firm cutoff date of March 31, 2026, for new orders of both models.

This is the first time Tesla has announced a hard global deadline for the Model S and X, as after that date, only existing inventory will be available in South Korea.

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The move to bring closure to the Model S and Model X aligns with CEO Elon Musk’s plans for Tesla moving forward. During the Q4 2025 Earnings Call in January, Musk said the two cars deserved an “honorable discharge” for what they have done for the company.

The long-running programs are primarily being removed so that manufacturing lines can be repurposed for high-volume manufacturing of the Optimus humanoid robot. Tesla is targeting a production rate of up to one million units each year.

The Model S and Model X being removed from Tesla’s plans is a tough choice, but it was one that was written on the wall. Sales of these premium models have declined sharply in recent years, and even with Plaid configurations that are performance-forward, the company still has had trouble getting them sold.

In 2025, the Model S and Model X together accounted for roughly 3 percent of Tesla’s global deliveries, down significantly from prior periods as competition intensified in the luxury EV segment and buyers shifted toward more affordable options like the Model 3 and Model Y.

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The Model S saw sales drop over 50 percent year-over-year in some quarters, while the Model X faced similar pressures from rivals, including the Rivian R1S and BMW iX.

Despite their dwindling volume, the Model S and Model X remain technological showcases. The Plaid variants deliver blistering acceleration, advanced Full Self-Driving capability, and luxurious interiors.

The phase-out paves the way for Tesla’s strategic pivot toward autonomy, robotics, and higher-volume vehicles.

Tesla brings closure to flagship ‘sentimental’ models, Musk confirms

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Fremont will continue producing the refreshed Model 3 and Model Y, ensuring the factory remains a key automotive hub while expanding into robotics. Tesla has stated that the shift is not expected to result in job losses and could increase headcount as Optimus production ramps up.

For Tesla fans, the sunset represents a bittersweet moment. The Model S, introduced in 2012, proved EVs could compete with luxury sedans, while the Falcon-wing-door Model X set new standards for family haulers. Owners can expect continued software support and service for years to come.

Many fans have pushed for the Model X to hang around due to its appeal for families.

With the two cars heading out, Tesla’s priority now becomes its future products, especially that of the Optimus robot, which is the main reason for the S/X platform’s conclusion.

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Tesla shows off mysterious vehicle at Giga Texas

The mysterious structure, partially unboxed amid construction materials, has sparked widespread speculation among Tesla enthusiasts and analysts. Many are convinced it is the long-rumored Model Y L, the extended-wheelbase variant already popular in China, now arriving in Texas for potential U.S. production.

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Credit: Joe Tegtmeyer | X

Tesla seemingly showed off a mysterious vehicle at Giga Texas, one that seems to be completely different than anything the company currently makes for the U.S. market.

The vehicle, which was spotted on the plant’s property, appears to be similar to the Model Y L that has not yet launched in North America, and is currently built at Gigafactory Shanghai in China.

Drone pilot Joe Tegtmeyer captured intriguing footage at Tesla’s Giga Texas on March 23, 2026, revealing what appears to be a large, blue plastic-wrapped vehicle body resting inside a wooden shipping crate outdoors.

The mysterious structure, partially unboxed amid construction materials, has sparked widespread speculation among Tesla enthusiasts and analysts. Many are convinced it is the long-rumored Model Y L, the extended-wheelbase variant already popular in China, now arriving in Texas for potential U.S. production.

The images show an elongated silhouette that stands out from standard Model Y bodies. Side-by-side comparisons shared in replies to Tegtmeyer’s post highlight key differences: the rear door extends farther over the wheel arch than on a regular Model Y, and the rear glass appears to run all the way to the spoiler lip without the metal trim seen on shorter versions.

One overlay analysis noted that the visible proportions align precisely with the Chinese-market Model Y L, which measures approximately 4.98 meters long with a 3.04-meter wheelbase, which is about seven inches longer overall than the standard Model Y sold in the U.S.

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The vehicle is a bare “body-in-white” shell, typical of prototypes sent abroad for tooling validation and local manufacturing ramp-up. Tesla has already launched the six- and seven-seat Model Y L in China and other markets, where it offers roughly 10% more cargo space and greater family-friendly versatility.

This sighting fits Tesla’s broader strategy. Industry observers expect the company to localize Model Y L production at Giga Texas by mid-2026 to serve American families seeking extra room without stepping up to the larger Cybertruck or a future full-size SUV.

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Bringing the design stateside could add tens of thousands of annual deliveries while leveraging existing Model Y lines. People have been adamant that they want the Model Y L in the U.S., especially as Tesla plans to fade the Model X, the company’s most ideal vehicle for large families, out of production in the near future.

Tesla Model Y lineup expansion signals an uncomfortable reality for consumers

While Tesla has made no official comment, the timing, amid Giga Texas expansion and steady Model Y output, suggests the mysterious crate is more than a random prototype.

If confirmed as the Model Y L, it marks another step in Tesla’s effort to refresh its bestselling SUV for global demand. The vehicle would perform exceptionally well in the U.S., and despite the company’s rather mute stance on bringing it to America, this might be the biggest hint to date that it could be on the way.

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