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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)

Published

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.

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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Tesla reliability rankings skyrocket significantly in latest assessment

“They definitely have their struggles, but by continuing to refine and not make huge changes in their models, they’re able to make more reliable vehicles, and they’ve moved up our rankings.”

Published

5 hours ago

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December 4, 2025

By

Credit: Tesla

Tesla ranked in the Top 10 of the most reliable car companies for 2026, as Consumer Reports’ latest index showed significant jumps from the past two years.

In 2022, Tesla ranked 27th out of 28 brands. Last year, it came in 17th.

However, 2026’s rankings were different. CR‘s rankings officially included Tesla in the Top 10, its best performance to date.

Finishing tenth, the full Top 10 is:

  1. Subaru
  2. BMW
  3. Porsche
  4. Honda
  5. Toyota
  6. Lexus
  7. Lincoln
  8. Hyundai
  9. Acura
  10. Tesla

Tesla has had steady improvements in its build quality, and its recent refinements of the Model 3 and Model Y have not gone unnoticed.

The publication’s Senior Director of Auto Testing, Jake Fisher, said about Tesla that the company’s ability to work through the rough patches has resulted in better performance (via CNBC):

“They definitely have their struggles, but by continuing to refine and not make huge changes in their models, they’re able to make more reliable vehicles, and they’ve moved up our rankings.”

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He continued to say that Tesla’s vehicles have become more reliable over time, and its decision to avoid making any significant changes to its bread-and-butter vehicles has benefited its performance in these rankings.

Legacy automakers tend to go overboard with changes, sometimes keeping a model name but recognizing a change in its “generation.” This leads to constant growing pains, as the changes in design require intense adjustments on the production side of things.

Instead, Tesla’s changes mostly come from a software standpoint, which are delivered through Over-the-Air updates, which improve the vehicle’s functionality or add new features.

Only one Tesla vehicle scored below average in Consumer Reports’ rankings for 2026 was the Cybertruck. Fisher’s belief that Tesla improves its other models over time might prove to be true with Cybertruck in a few years.

Tesla Cybertruck gets reviewed by Consumer Reports

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He continued:

“They’re definitely improving by keeping with things and refining, but if you look at their 5- to 10-year-old models that are out there, when it comes to reliability, they’re dead last of all the brands. They’re able to improve the reliability if they don’t make major changes.”

Regarding Subaru’s gold medal placing on the podium, Fisher said:

“While Subaru models provide good performance and comfort, they also excel in areas that may not be immediately apparent during a test drive.”

Other notable brands to improve are Rivian, which bumped itself slightly from 31 to 26. Chevrolet finished 24th, GMC ended up 29th, and Ford saw itself in 18th.

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Tesla Full Self-Driving v14.2.1 texting and driving: we tested it

We decided to test it, and our main objective was to try to determine a more definitive label for when it would allow you to grab your phone and look at it without any nudge from the in-car driver monitoring system.

Published

15 hours ago

on

December 4, 2025

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Credit: Grok

On Thursday, Tesla CEO Elon Musk said that Full Self-Driving v14.2.1 would enable texting and driving “depending on [the] context of surrounding traffic.”

Tesla CEO Elon Musk announces major update with texting and driving on FSD

We decided to test it, and our main objective was to try to determine a more definitive label for when it would allow you to grab your phone and look at it without any nudge from the in-car driver monitoring system.

I’d also like to add that, while Tesla had said back in early November that it hoped to allow this capability within one to two months, I still would not recommend you do it. Even if Tesla or Musk says it will allow you to do so, you should take into account the fact that many laws do not allow you to look at your phone. Be sure to refer to your local regulations surrounding texting and driving, and stay attentive to the road and its surroundings.

The Process

Based on Musk’s post on X, which said the ability to text and drive would be totally dependent on the “context of surrounding traffic,” I decided to try and find three levels of congestion: low, medium, and high.

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I also tried as best as I could to always glance up at the road, a natural reaction, but I spent most of my time, during the spans of when it was in my hand, looking at my phone screen. I limited my time looking at the phone screen to a few seconds, five to seven at most. On local roads, I didn’t go over five seconds; once I got to the highway, I ensured the vehicle had no other cars directly in front of me.

Also, at any time I saw a pedestrian, I put my phone down and was fully attentive to the road. I also made sure there were no law enforcement officers around; I am still very aware of the law, which is why I would never do this myself if I were not testing it.

I also limited the testing to no more than one minute per attempt.

I am fully aware that this test might ruffle some feathers. I’m not one to text and drive, and I tried to keep this test as abbreviated as possible while still getting some insight on how often it would require me to look at the road once again.

The Results

Low Congestion Area

I picked a local road close to where I live at a time when I knew there would be very little traffic. I grabbed my phone and looked at it for no more than five seconds before I would glance up at the road to ensure everything was okay:

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Looking up at the road was still regular in frequency; I would glance up at the road after hitting that five-second threshold. Then I would look back down.

I had no nudges during this portion of the test. Traffic was far from even a light volume, and other vehicles around were very infrequently seen.

Medium Congestion Area

This area had significantly more traffic and included a stop at a traffic light. I still kept the consecutive time of looking at my phone to about five seconds.

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I would quickly glance at the road to ensure everything was okay, then look back down at my phone, spending enough time looking at a post on Instagram, X, or Facebook to determine what it was about, before then peeking at the road again.

There was once again no alert to look at the road, and I started to question whether I was even looking at my phone long enough to get an alert:

Based on past versions of Full Self-Driving, especially dating back to v13, even looking out the window for too long would get me a nudge, and it was about the same amount of time, sometimes more, sometimes less, I would look out of a window to look at a house or a view.

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High Congestion Area

I decided to use the highway as a High Congestion Area, and it finally gave me an alert to look at the road.

As strange as it is, I felt more comfortable looking down at my phone for a longer amount of time on the highway, especially considering there is a lower chance of a sudden stop or a dangerous maneuver by another car, especially as I was traveling just 5 MPH over in the left lane.

This is where I finally got an alert from the driver monitoring system, and I immediately put my phone down and returned to looking at the road:

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Once I was able to trigger an alert, I considered the testing over with. I think in the future I’d like to try this again with someone else in the car to keep their eyes on the road, but I’m more than aware that we can’t always have company while driving.

My True Thoughts

Although this is apparently enabled based on what was said, I still do not feel totally comfortable with it. I would not ever consider shooting a text or responding to messages because Full Self-Driving is enabled, and there are two reasons for that.

The first is the fact that if an accident were to happen, it would be my fault. Although it would be my fault, people would take it as Tesla’s fault, just based on what media headlines usually are with accidents involving these cars.

Secondly, I am still well aware that it’s against the law to use your phone while driving. In Pennsylvania, we have the Paul Miller Law, which prohibits people from even holding their phones, even at stop lights.

I’d feel much more comfortable using my phone if liability were taken off of me in case of an accident. I trust FSD, but I am still erring on the side of caution, especially considering Tesla’s website still indicates vehicle operators have to remain attentive while using either FSD or Autopilot.

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Check out our full test below:

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Elon Musk

Tesla CEO Elon Musk announces major update with texting and driving on FSD

“Depending on context of surrounding traffic, yes,” Musk said in regards to FSD v14.2.1 allowing texting and driving.

Published

19 hours ago

on

December 4, 2025

By

Credit: carwow/YouTube

Tesla CEO Elon Musk has announced a major update with texting and driving capabilities on Full Self-Driving v14.2.1, the company’s latest version of the FSD suite.

Tesla Full Self-Driving, even in its most mature and capable versions, is still a Level 2 autonomous driving suite, meaning it requires attention from the vehicle operator.

You cannot sleep, and you should not take attention away from driving; ultimately, you are still solely responsible for what happens with the car.

The vehicles utilize a cabin-facing camera to enable attention monitoring, and if you take your eyes off the road for too long, you will be admonished and advised to pay attention. After five strikes, FSD and Autopilot will be disabled.

However, Musk announced at the Annual Shareholder Meeting in early November that the company would look at the statistics, but it aimed to allow people to text and drive “within the next month or two.”

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He said:

“I am confident that, within the next month or two, we’re gonna look at the safety statistics, but we will allow you to text and drive.”

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Today, Musk confirmed that the current version of Full Self-Driving, which is FSD v14.2.1, does allow for texting and driving “depending on context of surrounding traffic.”

There are some legitimate questions with this capability, especially as laws in all 50 U.S. states specifically prohibit texting and driving. It will be interesting to see the legality of it, because if a police officer sees you texting, they won’t know that you’re on Full Self-Driving, and you’ll likely be pulled over.

Some states prohibit drivers from even holding a phone when the car is in motion.

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It is certainly a move toward unsupervised Full Self-Driving operation, but it is worth noting that Musk’s words state it will only allow the vehicle operator to do it depending on the context of surrounding traffic.

He did not outline any specific conditions that FSD would allow a driver to text and drive.

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