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SpaceX’s Starship hopper spotted with trio of dual-bell Raptor engines

Starship revealed a trio of what appear to be new Raptor engines when SpaceX technicians moved the assembly from stand to ground. (NSF - bocachicagal)

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Following a brief ‘hop’ (via crane) off of a concrete build stand, the aft section of SpaceX’s first full-scale Starship hopper (Starhopper?) revealed that SpaceX technicians have already installed what appear to be three real Raptor engines, presumably the first time the propulsion system has ever been mounted to something that might eventually fly.

For a number of reasons, there is a strong chance that these Raptors are actually just boilerplate placeholders standing in as structural guides for the real deal some months down the line. On the other hand, there are also a number of reasons to assume that these apparent engines are indeed real Raptors.

Despite an already shocking series of rapid-fire developments in the South Texas Starhopper saga, the abrupt appearance of what appears to be three Raptor engines – mirroring CEO Elon Musk’s recent statement that the test vehicle would sport three Raptors – is by far the most unexpected moment yet for the prototype Starship. Purportedly a full-scale prototype of BFR’s upper stage/spaceship (now known as Starship), Musk indicated over the last two weeks that the hopper has been designed to perform a number of hop tests in which the craft’s three Raptors would power it to a range of (relatively low) altitudes above Boca Chica, Texas.

According to a recent FCC filing related to this test program, SpaceX is currently seeking a license for Starship hop tests that will not exceed 5 km (3.1 mi) in altitude and/or 6 minutes in duration. There is admittedly nothing mentioned about the maximum allowed velocity during those tests, but – much like Blue Origin performs supersonic tests of New Shepard in Cape Horn, Texas – SpaceX will likely seek and be granted permission to break the sound barrier during those hypothetical tests. Nevertheless, a 5km ceiling is a fairly significant cap on the range of performance Starhopper will be able to test – accelerating vertically at 2Gs, Starhopper could travel from sea level to 5km in less than 30 seconds while reaching speeds no higher than Mach 1-1.5.

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Combined with the apparent fact that this Starhopper’s fins seem unlikely to ever actuate (i.e. no aerodynamic control surfaces), it’s probable that this ad hoc prototype is only meant to perform a very limited range of hop tests, perhaps as basic as ironing out the kinks of operating a trio of gimballed Raptors and ensuring that they can safely and reliably launch, hover, and land a very large Starship-shaped mass simulator. Falcon 9’s Grasshopper and F9R reusability testbeds performed a very similar task some five years ago, offering SpaceX engineers the opportunity to optimize software and hardware needed to reliably recover real orbital-class rockets after launch. Although Falcon 9 has nine gimballed Merlin 1D engines, SpaceX has long sided with the sole center Merlin as the dedicated landing engine and has only briefly experimented with triple-Merlin landing burns.

Dual-expansion whaaaaat?

According to Musk, Raptor –  an advanced liquid methane and oxygen engine with a uniquely efficient propulsion cycle – was expected to produce an impressive ~2000 kN (200 ton, 450K lbf) of thrust in its finished form as of September 2018. However, Musk also mentioned in a late-2017 Reddit AMA that SpaceX engineers were modifying the ship’s design to ensure engine-out reliability during all regimes of flight, landing in particular. To accomplish this feat with an engine as powerful as Raptor, two or three Raptors – capable of producing as much as 600 tons of thrust total – would need to reliably throttle as low as 25%, assuming a landing mass of around 150t. To allow a nearly empty ship (~100t) to still reliably land with three Raptors ignited, the engines would need to be able to throttle to 20% or less.

A trio of Raptors (or Raptor stand-ins) were spotted on Starhopper on Dec 31 by NASASpaceflight user bocachicagal.

Known as deep throttling in rocketry, ensuring stable combustion and thrust at 20% (let alone 40%) throttle is an extraordinarily challenging feat, often subjecting engines to forces that can literally tear non-optimized hardware apart. To achieve such a deep throttle capability without excessively disrupting the engine’s design, SpaceX appears to have potentially sided with less efficient but extremely simple alternative, known as a dual-bell (or dual-expansion) rocket nozzle. A 1999 Rocketdyne paper concisely explained the primary draws of such a nozzle:

“The [altitude-compensating] dual-bell nozzle offers a unique combination of performance, simplicity, low weight, and ease of cooling” – Horn & Fisher, 1999

Given that SpaceX has decided to delay the introduction and certification of a vacuum-optimized Raptor engine, choosing to instead use the same Raptor on both BFR stages, something like a dual-bell nozzle would be one of the best possible ways for the company to retain some of the efficiency benefits of a vacuum engine while also drastically improving design simplicity, ease of manufacturing, and cutting development time. Aside from offering efficiency gains by way of altitude compensation, a dual-bell nozzle also happens to enable a given engine to operate a much wider throttle range by mitigating problems with flow separation and instability.

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For Starhopper and Starship, both aspects are an undeniable net-gain and it’s entirely possible that these dual-bell nozzles – if successfully demonstrated – could find their way onto Falcon 9 and Falcon Heavy to further boost their booster performance and efficiency.


For prompt updates, on-the-ground perspectives, and unique glimpses of SpaceX’s rocket recovery fleet check out our brand new LaunchPad and LandingZone newsletters!

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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Investor's Corner

Elon Musk drops a Thanksgiving hint about Starship’s biggest test yet

Elon Musk says Starship Flight 15 will try to catch the ship itself, a first.

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Elon Musk says SpaceX’s next Starship flight will try something nobody has done before, by catching the ship itself. Speaking to roughly 2,000 people at the X Takeover event at Giga Texas on Saturday, Musk said Flight 15 is about four to six weeks away and “probably launches a little bit before Thanksgiving, is my guess.”

That is a slip from earlier reporting, which had pointed to a launch as early as October 19. Musk explained why the date keeps moving. “We’re making a bunch of improvements to the rocket between every flight,” he said, adding that there are often hundreds, sometimes thousands, of small changes. This time the list is short, “but some of them take a fair bit of work and we’ve got to go inside the tank to make some of these changes.”

“We’re going to try to catch the ship, which is a super big deal,” Musk said. “If we do so, that’ll be the first time that there’s been full recovery of an orbital class rocket.” SpaceX has already caught the Super Heavy booster with the tower’s mechanical arms, and has talked about catching the ship since late 2025, but the upper stage has never been caught.

Musk also laid out what comes after. “The next big milestone would be to refly both the booster and the ship,” he said, describing a Flight 16 where “all parts of an orbital rocket are reflown.”

The reason SpaceX wants this comes down to cost and cadence. Every Starship ship so far has ended its flight in the ocean, and SpaceX expects most of those water landings to end in fireballs. A ship that returns to Starbase intact can be inspected and flown again. SpaceX’s IPO filing, says Starship V3 is designed to deliver 100 metric tons to orbit in a fully reusable configuration, that SpaceX aims to cut the cost to reach orbit by 99% or more versus the historical average, and that tower catches should allow “multiple launches per day.”

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The payoff goes beyond cheaper launches. The next generation Starlink V3 satellites are too large for Falcon 9 and can only fly on Starship, which can carry up to 60 per flight. Flight 14 on September 28 deployed the first 26 of them after Starship reached orbit despite an early engine shutdown, as Teslarati reported. Musk blamed engine computer software, and said the heat shield “was extremely robust,” which he claimed in August had solved Starship’s biggest challenge.

NASA’s Moon plans depend on the same capability. NASA’s inspector general has described a lander mission that needs a propellant depot in low Earth orbit and more than 10 tanker flights, with SpaceX targeting one tanker launch every six days. That schedule only works if ships and boosters come back fast and fly again. Also, ship to ship propellant transfer has not been attempted yet.

One interesting hurdle yet to be explored is bringing the ship back to the launch site, with reentry over land, which will undoubtedly come with a lot of aviation safety reviews.

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Elon Musk

Elon Musk’s surprise addition to the X Takeover lineup has fans talking

Elon Musk will join Saturday’s X Takeover at Giga Texas for a live virtual interview.

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Credit: Tesla Owners Silicon Valley
Credit: Tesla Owners Silicon Valley

Elon Musk will join X Takeover at Giga Texas on Saturday for a live virtual interview, according to Sawyer Merritt, who shared the news late Thursday. Musk will not be on stage in Austin. The conversation is set to stream for free on the @teslaownersSV account on X.

Organizers had kept expectations in check. In a September update, Tesla Owners Silicon Valley said Musk had appeared at the event twice before but was not promising a third appearance, even as fans hoped he would walk the Giga Texas grounds in person. A virtual spot matches 2024, when Musk gave a surprise interview of about an hour to the crowd in San Luis Obispo, as Teslarati reported at the time.

This year’s edition is a first in several ways. It is the first X Takeover held outside California and the first at a Tesla facility, with tickets selling out in eight days. Tesla provides the venue, but the event is produced independently by Tesla Owners Silicon Valley. The main event runs from 10 a.m. to 6 p.m. CT, followed by a drone and light show at 9 p.m. Maye Musk is the keynote speaker, Franz von Holzhausen is set for a virtual keynote, and Nicki Minaj is the special guest. Joe Tegtmeyer, whose drone footage Teslarati used to track the Optimus factory steel frame at Giga Texas, is also on the speaker list.

Musk’s interview topics have not been revealed, but the backdrop is busy. Tesla doubled its Cybercab fleet in Austin in late September, and last week Musk explained why Robotaxi hours only moved from 10 p.m. to 11 p.m.. Merritt also reported Thursday that Texas DMV records now show 319 registered Cybercabs, up from 169. NHTSA’s deadline for Tesla’s sworn answers on Cybercab certification is October 30, and Tesla reports third quarter earnings on October 21.

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Fans who cannot make it to Austin can watch the livestream on X. Musk tends to say more in unscripted settings than he does in prepared remarks, which is the reason this one is worth having open on Saturday.

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SpaceX brings four astronauts home after 8 months in space, and the return was flawless

SpaceX Crew Dragon Freedom returned four Crew-12 astronauts home after 237 days aboard the station.

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SpaceX's Crew Dragon Freedom sits aboard the recovery ship Shannon after splashing down off the coast of Los Angeles with the Crew-12 astronauts on October 8, 2026. (Credit: SpaceX)
SpaceX's Crew Dragon Freedom sits aboard the recovery ship Shannon after splashing down off the coast of Los Angeles with the Crew-12 astronauts on October 8, 2026. (Credit: SpaceX)

Four Crew-12 members are back on Earth after 237 days at the International Space Station. SpaceX’s Crew Dragon Freedom splashed down in the Pacific Ocean about 50 miles west of Los Angeles at 11:34 a.m. ET on Thursday.

NASA astronauts Jessica Meir and Jack Hathaway, ESA astronaut Sophie Adenot, and Roscosmos cosmonaut Andrey Fedyaev landed one day after undocking from the station’s Harmony module at 8:05 a.m. ET on Wednesday. NASA confirmed the splashdown minutes later. SpaceX had flagged the 27.5 hour trip home on X while Dragon was still firing its departure burns away from the station.

The descent ran on schedule when Freedom started a nine minute deorbit burn at 10:46 a.m. ET, then hit the thicker atmosphere about 36 minutes later at nearly five miles per second. Chutes deployed at around 18,000 feet, and four main parachutes brought the capsule down to roughly 15 mph at splashdown.

SpaceX fast boats secured Dragon before the recovery ship Shannon hoisted it onto the deck with the crew still inside. Flight surgeons on board ran initial medical checks. All four crew members will be flown ashore by helicopter and then head to NASA’s Johnson Space Center in Houston for rehabilitation.

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Crew-12 launched on February 13 from Space Launch Complex 40 at Cape Canaveral, a flight that also marked the first Falcon 9 booster landing at SpaceX’s new LZ-40 pad. Over the mission, the crew completed 3,792 orbits, covered nearly 101 million miles, and carried out four spacewalks to maintain and upgrade the station.

Meir now has 440 cumulative days in space, which places her in NASA’s top 10. This was the first spaceflight for Hathaway and for Adenot, a French Air Force colonel and former helicopter pilot. Fedyaev, who spent 186 days in orbit on Crew-6 in 2023, has now flown two long duration Dragon missions.

The return closes out a busy stretch of Dragon traffic. Crew-13 arrived on October 1 aboard Crew Dragon Grace, which docked just 7 hours and 55 minutes after liftoff, the fastest launch to docking of any U.S. spacecraft in ISS history. Commander Jessica Watkins, pilot Luke Delaney, Canadian Space Agency astronaut Joshua Kutryk, and cosmonaut Sergey Teteryatnikov remain aboard alongside the three person Soyuz MS-29 crew.

With Crew-12 gone, the port is clear for CRS-35, a cargo Dragon carrying the final pair of ISS Roll-Out Solar Arrays. NASA is holding a post-splashdown teleconference at 1:15 p.m. ET covering both the crew’s return and the upcoming cargo launch.

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