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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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Tesla’s newest “Folding V4 Superchargers” are key to its most aggressive expansion yet

Tesla’s folding V4 Supercharger ships 33% more per truck, cuts deployment time and cost significantly.

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Tesla V4 Supercharger installation ramping in Europe

Tesla is rolling out a folding V4 Supercharger design, an engineering change that allows 33% more units to fit on a single delivery truck, cuts deployment time in half, and reduces overall installation cost by roughly 20%.

The folding mechanism addresses one of the least glamorous but most consequential bottlenecks in charging infrastructure: getting hardware from factory floor to job site efficiently. By collapsing the form factor for transit and unfolding into an operational configuration on arrival, the new design dramatically reduces the logistics overhead that has historically slowed Supercharger rollouts, particularly at large or remote sites where multiple units are needed simultaneously.

The timing aligns with a broader acceleration in Tesla’s network strategy. In March 2026, Tesla’s Gigafactory New York produced its final V3 Supercharger cabinet after more than seven years and 15,000 units, pivoting entirely to V4 cabinet production. The V4 cabinet itself is already a generational leap, delivering up to 500 kW per stall for passenger vehicles and up to 1.2 MW for the Tesla Semi, while supporting twice the stalls per cabinet at three times the power density of its predecessor. The folding transport innovation layers logistical efficiency on top of that technical foundation.

Tesla launches first ‘true’ East Coast V4 Supercharger: here’s what that means

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Tesla Charging’s Director Max de Zegher, commenting on the V4 cabinet when it launched, captured the operational philosophy behind these changes: “Posts can peak up to 500kW for cars, but we need less than 1MW across 8 posts to deliver maximum power to cars 99% of the time.” The design philosophy has always been about maximizing real-world throughput, not just peak specs, and the folding transport upgrade extends that thinking into the supply chain itself.

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The Boring Company clears final Nashville hurdle: Music City loop is full speed ahead

The Boring Company has cleared its final Nashville hurdles, putting the Music City Loop on track for 2026.

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The Boring Company has cleared one of its most significant regulatory milestones yet, securing a key easement from the Music City Center in Nashville just days ago, the latest in a series of approvals that have pushed the Music City Loop project firmly into construction reality.

On March 24, 2026, the Convention Center Authority voted to grant The Boring Company access to an easement along the west side of the Music City Center property, allowing tunneling beneath the privately owned venue. The move follows a unanimous 7-0 vote by the Metro Nashville Airport Authority on February 18, and a joint state and federal approval from the Tennessee Department of Transportation and the Federal Highway Administration on February 25. Together, these green lights have cleared the path for a roughly 10-mile underground tunnel connecting downtown Nashville to Nashville International Airport, with potential extensions into midtown along West End Avenue.

Music City Loop could highlight The Boring Company’s real disruption

Nashville was selected by The Boring Company largely because of its rapid population growth and the strain that growth has placed on surface infrastructure. Traffic has become a persistent problem for residents, convention visitors, and airport travelers alike. The Music City Loop promises an approximately 8-minute underground transit time between downtown and the Nashville International Airport (BNA), removing thousands of vehicles from surface roads daily while operating as a fully electric, zero-emissions system at no cost to taxpayers.

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The project fits squarely within a broader vision Musk has championed for years. In responding to a breakdown of the Loop’s construction costs, Musk posted on X: “Tunnels are so underrated.” The comment reflected a longstanding belief that underground transit represents one of the most cost-effective and scalable infrastructure solutions available. The Boring Company has claimed it can build 13 miles of twin tunnels in Nashville for between $240 million and $300 million total, a fraction of what comparable projects cost elsewhere in the country.

The Las Vegas Loop, The Boring Company’s first operational system, has served as a proof of concept. During the CONEXPO trade show in March 2026, the Vegas Loop transported approximately 82,000 passengers over five days at the Las Vegas Convention Center, demonstrating the system’s capacity during large-scale events. Nashville draws millions of convention visitors and tourists each year, and local business leaders have pointed to that same capacity as a major draw for supporting the project.

The Music City Loop was first announced in July 2025. Construction began within hours of the February 25 state approval, with The Boring Company’s Prufrock tunneling machine already in the ground the same evening. The first operational segment is targeted for late 2026, with the full route expected to be complete by 2029. The project represents one of the largest privately funded infrastructure efforts currently underway in the United States.

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Elon Musk

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

A banner on the post read “Katie McCormick supports this,” using LinkedIn’s heart-in-hand “support” icon, an endorsement stronger than a simple “like.” Musk’s lawyers argue the action creates “a perception of bias against Mr. Musk,” warranting immediate recusal to preserve judicial impartiality.

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elon musk
Ministério Das Comunicações, CC BY 2.0 , via Wikimedia Commons

Tesla CEO Elon Musk’s legal team has filed a motion demanding that Delaware Chancellor Kathaleen McCormick disqualify herself from an ongoing high-stakes Tesla shareholder lawsuit.

The filing, submitted March 25, cites an apparent LinkedIn “support” reaction from McCormick’s account to a post celebrating a $2 billion jury verdict against Musk in a separate California securities-fraud case.

The move escalates long-simmering tensions between Musk, Tesla, and the Delaware judiciary, where McCormick previously presided over the landmark challenge to Musk’s record $56 billion 2018 compensation package.

Delaware Supreme Court reinstates Elon Musk’s 2018 Tesla CEO pay package

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The LinkedIn post was written by Harry Plotkin, a Southern California jury consultant who assisted the plaintiffs who sued Musk over 2022 tweets about his Twitter acquisition. Plotkin praised the trial team for “standing up for the little guy against the richest man in the world.”

The New York Post initially reported the story.

A banner on the post read “Katie McCormick supports this,” using LinkedIn’s heart-in-hand “support” icon, an endorsement stronger than a simple “like.” Musk’s lawyers argue the action creates “a perception of bias against Mr. Musk,” warranting immediate recusal to preserve judicial impartiality.

McCormick swiftly denied intentional endorsement. In a letter to attorneys, she stated she was unaware of the interaction until LinkedIn notified her. She wrote:

“I either did not click the ‘support’ icon at all, or I did so accidentally. I do not believe that I did it accidentally.”

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The chancellor maintains the reaction was inadvertent, but critics, including Musk allies, call the explanation implausible given the platform’s deliberate interface.

McCormick’s central role in the Tesla pay-package litigation underscores the stakes. In Tornetta v. Musk, in January 2024, she ruled the 2018 performance-based stock-option grant, potentially worth $56 billion at the time and now valued far higher, was invalid.

The package consisted of 12 tranches of options, each vesting only after Tesla achieved ambitious market-cap and operational milestones. McCormick found Musk exercised “transaction-specific control” over Tesla as a controlling stockholder, the board lacked sufficient independence, and proxy disclosures to shareholders were materially deficient.

Applying the entire-fairness standard, she concluded defendants failed to prove the deal was fair in process or price and ordered full rescission, an “unfathomable” remedy she described as necessary to deter fiduciary breaches.

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After the ruling, Tesla shareholders ratified the package a second time in June 2024. McCormick rejected that ratification in December 2024, holding that post-trial votes could not cure defects.

Tesla appealed. On December 19 of last year, the Delaware Supreme Court unanimously reversed the rescission remedy while largely leaving McCormick’s liability findings intact. The high court deemed total unwinding inequitable and impractical, restoring the package but awarding the plaintiff only nominal $1 damages plus reduced attorneys’ fees. Musk ultimately received the full award.

The current recusal motion arises in yet another Tesla derivative suit before McCormick. Legal observers say granting it could signal heightened scrutiny of judicial social-media activity; denial might reinforce perceptions of an insular Delaware bench.

Broader fallout includes accelerated corporate migration out of Delaware, Musk himself moved Tesla’s incorporation to Texas after the first ruling, and renewed debate over whether the state’s specialized courts remain the gold standard for corporate governance disputes.

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A decision is expected soon; whichever way it lands, the episode highlights the fragile balance between judicial independence and public confidence in high-profile litigation.

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