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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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7 years ago

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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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Tesla Optimus Gen 3 is coming to the Tesla Diner with new ambitions

Tesla’s Optimus robot left the Hollywood Diner within months of opening. Now Musk is planning its return with a bigger role and a major Gen 3 upgrade underway.

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6 hours ago

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March 30, 2026

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Tesla Optimus Gen 3 [Credit: Tesla]

Tesla’s Optimus robot was one of the most talked-about features when the Tesla Diner opened on Santa Monica Boulevard in Hollywood on July 21, 2025. Dubbed “Poptimus” by Tesla fans, the Gen 2 robot stood upstairs at the retro-futuristic, drive-in theater and Tesla Supercharging station, scooping popcorn into bags and handing them to guests with a wave.

The diner itself had been years in the making. Elon Musk first floated the idea in 2018 with a tweet about building an “old-school drive-in, roller skates & rock restaurant” at a Hollywood Supercharger. What eventually opened was a unique two-story neon-lit space, with 80 EV charging stalls, and Optimus serving as a live demonstration of where Tesla’s ambitions were headed.


But Optimus did not stay long, and was gone by December 2025.

Now, the robot is set to return with a more demanding job. Musk has ambitions for Optimus to take on a food runner role in 2026, delivering meals directly to cars at the Supercharger stalls. While the latest Gen 3 Optimus is likely to initially take on its previous popcorn-serving role, it wouldn’t be out of the question for Optimus to see a quick promotion. With improved  hand dexterity that features 50 total actuators and 22 degrees of freedom per hand, and significantly more powerful processing through Tesla’s latest AI5 chip that includes Grok-powered voice interaction, Musk described Optimus at the Abundance Summit on March 12, 2026, as “by far the most advanced robot in the world, Nothing’s even close.”

That confidence is backed by a major manufacturing shift. At the Q4 2025 earnings call in January, Musk announced Tesla would discontinue the Model S and Model X and convert those Fremont production lines to build Optimus. “It’s time to basically bring the Model S and X programs to an end,” he said, calling for a pivot that reflects where the Tesla’s future lies.

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Musk forces Judge’s exit from shareholder battles over viral social media slip-up

McCormick insisted in a court filing that she harbors no actual bias against Musk or the defendants. She claimed she either never clicked the “support” button, LinkedIn’s version of a “like,” or did so accidentally.

Published

10 hours ago

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March 30, 2026

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(Credit: Tesla)

Many Tesla fans are familiar with the name Kathaleen McCormick, especially if they are investors in the company.

McCormick is a Delaware Chancery Court Judge who presided over Tesla CEO Elon Musk’s pay package lawsuit over the past few years, as well as his purchase of Twitter. However, she will no longer be sitting in on any issues related to Musk.

Elon Musk demands Delaware Judge recuse herself after ‘support’ post celebrating $2B court loss

In a rare admission of potential optics issues in one of America’s most powerful corporate courts, Delaware Chancery Court Chancellor Kathaleen McCormick stepped aside Monday from a cluster of shareholder lawsuits targeting Elon Musk and Tesla’s board.

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The move came just days after Musk’s legal team highlighted her apparent “support” on LinkedIn for a post that mocked the billionaire over his 2022 tweets about the $44 billion Twitter acquisition.

McCormick insisted in a court filing that she harbors no actual bias against Musk or the defendants. She claimed she either never clicked the “support” button, LinkedIn’s version of a “like,” or did so accidentally.

She wrote in a newly published memo from the Delaware Chancery Court:

“The motion for recusal rests on a false premise — that I support a LinkedIn post about Mr. Musk, which I do not in fact support. I am not biased against the defendants in these actions.”

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Yet she granted the reassignment anyway, acknowledging that the intense media scrutiny surrounding her involvement had become “detrimental to the administration of justice.”

The consolidated cases will now be handled by three of her colleagues on the Delaware Court of Chancery, the nation’s go-to venue for high-stakes corporate disputes. The lawsuits accuse Musk and Tesla directors of breaching fiduciary duties through lavish executive compensation and lax governance oversight.

One prominent claim, filed by a Detroit pension fund, challenges massive stock awards granted to board members, alleging the payouts harmed the company. The litigation also overlaps with issues stemming from Musk’s turbulent 2022 Twitter purchase.

McCormick’s history with Musk made her a lightning rod. In 2022, she presided over the fast-tracked lawsuit that ultimately forced Musk to complete the Twitter deal after he tried to back out.

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Then in 2024, she struck down his record $56 billion Tesla compensation package, ruling the approval process was flawed and overly CEO-friendly. The Delaware Supreme Court later reinstated the pay on technical grounds, but the ruling fueled Musk’s long-standing criticism of the state’s judiciary.

Musk has repeatedly urged companies to reincorporate elsewhere, arguing Delaware courts have grown hostile to visionary leaders. Monday’s recusal hands him a symbolic victory and underscores how personal social-media activity can collide with judicial impartiality standards.

Delaware law requires judges to step aside if there’s even a “reasonable basis” to question their neutrality.

Court watchers say the episode highlights growing tensions in corporate America’s legal epicenter. While McCormick maintained her impartiality, the appearance of bias proved too costly to ignore. The cases will proceed without her, but the broader debate over Delaware’s dominance in business litigation is far from over.

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Elon Musk has generous TSA offer denied by the White House: here’s why

Musk stepped in on March 21 via a post on X, writing: “I would like to offer to pay the salaries of TSA personnel during this funding impasse that is negatively affecting the lives of so many Americans at airports throughout the country.”

Published

12 hours ago

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March 30, 2026

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Gage Skidmore, CC BY-SA 4.0 , via Wikimedia Commons

Tesla and SpaceX CEO Elon Musk made a generous offer to pay the salaries of Transportation Security Administration (TSA) employees last week, but the offer was denied by the White House.

In a striking display of private-sector initiative clashing with federal bureaucracy, the White House has turned down an offer from Elon Musk to personally cover the salaries of TSA officers amid an ongoing partial government shutdown. The rejection, reported last Wednesday by multiple outlets, highlights the legal and political hurdles facing unconventional solutions to Washington’s funding gridlock.

The impasse began weeks ago when Congress failed to pass funding for the Department of Homeland Security (DHS), leaving TSA employees, essential workers who screen millions of travelers daily, without paychecks while still required to report for duty.

Frustrated travelers have endured record-long security lines at major airports, with reports of chaos and delays rippling across the country.

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Musk stepped in on March 21 via a post on X, writing: “I would like to offer to pay the salaries of TSA personnel during this funding impasse that is negatively affecting the lives of so many Americans at airports throughout the country.”

But it was not for no reason.

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White House spokesperson Abigail Jackson responded on behalf of the Trump administration, expressing appreciation for Musk’s gesture.

However, the legal obstacles, which would be insurmountable, would inhibit Musk from doing so. Jackson said:

“We greatly appreciate Elon’s generous offer. This would pose great legal challenges due to his involvement with federal government contracts.”

Musk’s companies hold significant federal contracts, including NASA launches through SpaceX and potential Defense Department work, raising concerns about conflicts of interest, ethics rules, and anti-bribery statutes that prohibit private payments to government employees. Administration officials also indicated they expect the shutdown to end soon, making external funding unnecessary.

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The episode underscores deeper tensions in Washington. Musk, who has advised on government efficiency efforts and maintains a close relationship with President Trump, has frequently criticized wasteful spending and bureaucratic delays.

His offer came as airport security lines ballooned, drawing public frustration toward both parties. TSA officers, many of whom rely on paychecks to cover mortgages and family expenses, have continued working without compensation, a situation that has drawn bipartisan concern but little immediate resolution.

Critics of the rejection argue it prioritizes red tape over practical relief for frontline workers and travelers. Supporters of the White House position counter that allowing private funding sets a dangerous precedent and could undermine congressional authority over the budget.

The White House eventually came to terms with the TSA on Friday and started paying them once again, and lines at airports instantly shrank.  The Department of Homeland Security (DHS) said that TSA staf would begin receiving paychecks “as early as” today.

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