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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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Tesla adjusts Robotaxi safety monitor strategy in Austin with new service area

The positioning of the driver, as well as the driver’s hands being closer to the steering wheel, is more similar to what Tesla is doing in the Bay Area Robotaxi program than it is to what it has done in Austin.

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Credit: @AdanGuajardo/X

Tesla has adjusted its Robotaxi safety monitor strategy in Austin after it expanded its service area in the city last week for the third time.

Tesla has been operating its Robotaxi platform in Austin since June 22. The vehicles have been operated without a driver, but Tesla has placed safety monitors in the passenger’s seat as a precaution.

The safety monitors are responsible for performing any necessary interventions and maintaining a safe and comfortable cabin for riders as they experience Tesla’s first venture into the driverless ride-sharing space.

Last week, Tesla expanded its service area in Austin for the third time, expanding it from about 90 square miles to 170 square miles. The expansion included new territory, including the Austin-Bergstrom International Airport, Tesla’s Gigafactory Texas, and several freeways.

Tesla Robotaxi geofence expansion enters Plaid Mode and includes a surprise

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The freeway is an area that is uncharted territory for the Tesla Robotaxi program, and this fact alone encouraged Tesla to switch up its safety monitor positioning for the time being.

For now, they will be riding in the driver’s seat when routes require freeway travel:

The positioning of the driver, as well as the driver’s hands being closer to the steering wheel, is more similar to what Tesla is doing in the Bay Area Robotaxi program than it is to what it has done in Austin.

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This is sure to draw criticism from skeptics, but it is simply a step to keep things controlled and safe while the first Robotaxi drives take passengers on the highway with this version of the Full Self-Driving software.

This FSD version differs from the one that customers have in their own vehicles, but CEO Elon Musk has indicated something big is coming soon. FSD v14 is coming to vehicles in the near future, and Musk has said its performance is pretty incredible.

Tesla’s Elon Musk shares optimistic teaser about FSD V14: “Feels sentient”

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Tesla has best month ever in Turkey with drastic spike in sales

Tesla managed to sell 8,730 Model Y vehicles in Turkey, outpacing almost every competitor by a substantial margin. Only one brand sold better than Tesla in August in Turkey, and it was Renault.

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Credit: Tesla

Tesla had its best monthly performance ever in Turkey in August, thanks to a drastic spike in sales.

Tesla saw an 86 percent bump in sales of the new Model Y in Turkey in August compared to July, dominating the market.

The performance was one of Tesla’s best in the market, and the company’s sales for the month accounted for half of all EV sales in Turkey for August, as it dominated and led BYD, which was the second-best-selling brand with just 1,639 units sold.

Tesla managed to sell 8,730 Model Y vehicles in Turkey, outpacing almost every competitor by a substantial margin. Only one brand sold better than Tesla in August in Turkey, and it was Renault.

Electric vehicles are, in some ways, more desirable than their gas counterparts in Turkey for several reasons. Most of the reasoning is financial.

First, EVs are subject to a lower Special Consumption Tax in Turkey. EVs can range from 25 percent to up to 170 percent, but this is less than the 70 to 220 percent rate that gas-powered vehicles can face. The tax is dependent on engine size.

Elon Musk courted to build a Tesla factory in Turkey

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Additionally, EVs are exempt from the annual Motor Vehicle Tax for the first ten years, providing consumers with a long-term ownership advantage. There are also credits that can amount to $30,000 in breaks, which makes them more accessible and brings down the cost of ownership.

Let’s not forget the other advantages that are felt regardless of country: cheaper fuel costs, reduced maintenance, and improved performance.

The base Model Y is the only configuration available in Turkey currently.

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Tesla is upgrading airbag safety through a crazy software update

“This upgrade builds upon your vehicle’s superior crash protection by now using Tesla Vision to help offer some of the most cutting-edge airbag performance in the event of a frontal crash.”

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(Credit: Tesla)

Tesla is upgrading airbag safety through a crazy software update, which will utilize the company’s vision-first approach to enable better protection in the event of an accident.

Over the years, Tesla has gained an incredible reputation for prioritizing safety in its vehicles, with crash test ratings at the forefront of its engineers’ minds.

This has led to Tesla gaining numerous five-star safety ratings and awards related to safety. It is not just a statistical thing, either. In the real world, we’ve seen Teslas demonstrate some impressive examples of crash safety.

Everything from that glass roof not caving in when a tree falls on it to a Model Y surviving a drive off a cliff has been recorded.

However, Tesla is always looking to improve safety, and unlike most companies, it does not need a physical hardware update to do so. It can enhance features such as crash response and airbag performance through Over-the-Air software updates, which download automatically to the vehicle.

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In Tesla’s 2025.32 Software Update, the company is rolling out a Frontal Airbag System Enhancement, which aims to use Tesla Vision, the company’s camera-based approach to self-driving, to keep occupants safe.

The release notes state (via NotaTeslaApp):

“This upgrade builds upon your vehicle’s superior crash protection by now using Tesla Vision to help offer some of the most cutting-edge airbag performance in the event of a frontal crash. Building on top of regulatory and industry crash testing, this release enables front airbags to begin to inflate and restrain occupants earlier, in a way that only Tesla’s integrated systems are capable of doing, making your car safer over time.”

The use of cameras to predict a better time to restrain occupants with seatbelts and inflate airbags prior to a collision is a fantastic way to prevent injuries and limit harm done to those in the vehicle.

The feature is currently limited to the Model Y.

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