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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.

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.

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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.

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

Elon Musk is now a remote DOGE worker: White House Chief of Staff

The Tesla and SpaceX CEO Elon Musk is no longer working from the West Wing.

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Credit: Elon Musk/X

In a conversation with the New York Post, White House Chief of Staff Susie Wiles stated that Tesla and SpaceX CEO Elon Musk is no longer working from the West Wing.

As per the Chief of Staff, Musk is still working for DOGE—as a remote worker, at least.

Remote Musk

In her conversation with the publication, Wiles stated that she still talks with Musk. And while the CEO is now working remotely, his contributions still have the same net effect. 

“Instead of meeting with him in person, I’m talking to him on the phone, but it’s the same net effect,” Wiles stated, adding that “it really doesn’t matter much” that the CEO “hasn’t been here physically.” She also noted that Musk’s team will not be leaving.

“He’s not out of it altogether. He’s just not physically present as much as he was. The people that are doing this work are here doing good things and paying attention to the details. He’ll be stepping back a little, but he’s certainly not abandoning it. And his people are definitely not,” Wiles stated.

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Back to Tesla

Musk has been a frequent presence in the White House during the Trump administration’s first 100 days in office. But during the Q1 2025 Tesla earnings call, Musk stated that he would be spending substantially less time with DOGE and substantially more time with Tesla. Musk did emphasize, however, that DOGE’s work is extremely valuable and critical.

“I think I’ll continue to spend a day or two per week on government matters for as long as the President would like me to do so and as long as it is useful. But starting next month, I’ll be allocating probably more of my time to Tesla and now that the major work of establishing the Department of Government Efficiency is done,” Musk stated.

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Tariff reprieve might be ‘Tesla-friendly,’ but it’s also an encouragement to others

Tesla stands to benefit from the tariff reprieve, but it has some work cut out for it as well.

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tesla employee
(Photo: Tesla)

After Secretary of Commerce Howard Lutnick made adjustments to the automotive tariff program that was initially announced, many quickly pointed to the reprieve as “Tesla-friendly.”

While that may be the case right now, it was also a nudge of encouragement to other companies, Tesla included, to source parts from the U.S. in an effort to strengthen domestic manufacturing. Many companies are close, and it will only take a handful of improvements to save themselves from tariffs on their cars as well.

Yesterday, Sec. Lutnick confirmed that cars manufactured with at least 85 percent of domestic content will face zero tariffs. Additionally, U.S. automakers would receive credit up to 15 percent of the value of vehicles to offset the cost of imported parts.

Big Tesla win? Sec Lutnick says cars with 85% domestic content will face zero tariffs

“This is ‘finish your cars in America and you win’,” Lutnick said.

Many were quick to point out that only three vehicles currently qualify for this zero-tariff threshold: all three are Teslas.

However, according to Kelley Blue Book’s most recent study that revealed who makes the most American cars, there are a lot of vehicles that are extremely close to also qualifying for these tariff reductions.

Tesla has three vehicles that are within five percent, while Ford, Honda, Jeep, Chevrolet, GMC, and Volkswagen have many within just ten percent of the threshold.

Tesla completely dominates Kogod School’s 2024 Made in America Auto Index

It is within reach for many.

Right now, it is easy to see why some people might think this is a benefit for Tesla and Tesla only.

But it’s not, because Tesla has its Cybertruck, Model S, and Model X just a few percentage points outside of that 85 percent cutoff. They, too, will feel the effects of the broader strategy that the Trump administration is using to prioritize domestic manufacturing and employment. More building in America means more jobs for Americans.

Credit: Tesla

However, other companies that are very close to the 85 percent cutoff are only a few components away from also saving themselves the hassle of the tariffs.

Ford has the following vehicles within just five percent of the 85 percent threshold:

  • Ford Mustang GT automatic (80%)
  • Ford Mustang GT 5.0 (80%)
  • Ford Mustang GT Coupe Premium (80%)

Honda has several within ten percent:

  • Honda Passport All-Wheel-Drive (76.5%)
  • Honda Passport Trailsport (76.5)

Jeep has two cars:

  • Jeep Wrangler Rubicon (76%)
  • Jeep Wrangler Sahara (76%)

Volkswagen has one with the ID.4 AWD 82-kWh (75.5%). GMC has two at 75.5% with the Canyon AT4 Crew Cab 4WD and the Canyon Denali Crew Cab 4WD.

Chevrolet has several:

  • Chevrolet Colorado 2.7-liter (75.5%)
  • Chevrolet Colorado LT Crew Cab 2WD 2.7-liter (75.5%)
  • Chevrolet Colorado Z71 Crew Cab 4WD 2.7-liter (75.5%)

These companies are close to reaching the 85% threshold, but adjustments need to be made to work toward that number.

Anything from seats to fabric to glass can be swapped out for American-made products, making these cars more domestically sourced and thus qualifying them for the zero-tariff boundary.

Frank DuBois of American University said that manufacturers like to see stability in their relationships with suppliers and major trade partners. He said that Trump’s tariff plan could cause “a period of real instability,” but it will only be temporary.

Now is the time to push American manufacturing forward, solidifying a future with more U.S.-made vehicles and creating more domestic jobs. Tesla will also need to scramble to make adjustments to its vehicles that are below 85%.

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Tesla Cybertruck RWD production in full swing at Giga Texas

Videos of several freshly produced Cybertruck LR RWD units were shared on social media platform X.

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Credit: Joe Tegtmeyer/X

It appears that Tesla is indeed ramping the production of the Cybertruck Long Range Rear Wheel Drive (LR RWD), the most affordable variant of the brutalist all-electric pickup truck.

Videos of several freshly produced Cybertruck LR RWD units were shared on social media platform X.

Giga Texas Footage

As per longtime Tesla watcher Joe Tegtmeyer, Giga, Texas, was a hotbed of activity when he conducted his recent drone flyover. Apart from what seemed to be Cybercab castings being gathered in the complex, a good number of Cybertruck LR RWD units could also be seen in the facility’s staging area. The Cybertruck LR RWD units are quite easy to spot since they are not equipped with the motorized tonneau cover that is standard on the Cybertruck AWD and Cyberbeast.

The presence of the Cybertruck LR RWD units in Giga Texas’ staging area suggests that Tesla is ramping the production of the base all-electric pickup truck. This bodes well for the vehicle, which is still premium priced despite missing a good number of features that are standard in the Cybertruck AWD and Cyberbeast.

Cybertruck Long Range RWD Specs

The Cybertruck LR RWD is priced at $69,990 before incentives, making it $10,000 more affordable than the Cybertruck AWD. For its price, the Cybertruck Long Range RWD offers a range of 350 miles per charge if equipped with its 18” standard Wheels. It can also add up to 147 miles of range in 15 minutes using a Tesla Supercharger.

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Much of the cost-cutting measures taken by Tesla are evident in the cabin of the Cybertruck LR RWD. This could be seen in its textile seats, standard console, seven-speaker audio system with no active noise cancellation, and lack of a 9.4” second-row display. It is also missing the motorized tonneau cover, the 2x 120V and 1x 240V power outlets on the bed, and the 2x 120V power outlets in the cabin. It is also equipped with an adaptive coil spring suspension instead of the adaptive air suspension in the Cybertruck AWD and Cyberbeast.

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