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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.

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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.

 

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.

 

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!

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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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Starlink makes a difference in Philippine province ravaged by typhoon

The Severe Tropical Storm battered the province, leaving communications networks in the area in shambles.

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Credit: Starlink/X

The Philippines’ Department of Information and Communications Technology (DICT) is using Starlink to provide connectivity in the municipality of Masbate, which was affected by Severe Tropical Storm Opong (international name Bualoi). 

The Severe Tropical Storm battered the province, leaving communications networks in the area in shambles.

Starlink units enhance connectivity

DICT Secretary Henry Aguda visited the province to assess internet and communications infrastructure and deliver 10 additional Starlink satellite units, according to the Philippine News Agency. The is move aimed at strengthening emergency response and restore digital access to the area.

Aguda met with Masbate Governor Richard Kho during his visit and joined telecommunications representatives in inspecting provincial offices, free charging stations, and Wi-Fi connectivity sites for residents. 

According to DICT officer-in-charge Rachel Ann Grabador, three Starlink units, 10 routers, and a 2kW solar-powered station have already been deployed in the province following the typhoon. The units have been installed at key facilities such as Masbate Airport’s communications tower and the Masbate Provincial Hospital’s administrative office. 

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Game-changing technology

Thanks to its global coverage and its capability to provide high-speed internet connectivity even in remote areas, Starlink has become the best communications solution that can be deployed in the aftermath of natural disasters. Its low-cost kits, which are capable of of providing fast internet speeds, are also portable, making them easy to deploy in areas that are damaged by natural disasters.

As noted in a Space.com report, there are currently 8,475 Starlink satellites in orbit, of which 8,460 are working, as of September 25, 2025. Initially, SpaceX had filed documents with International regulators to place about 4,000 Starlink satellites in Low Earth Orbit. Over time, however, the number of planned Starlink satellites has grown, with SpaceX aiming to launch as many as 42,000 Starlink satellites to fully connect the globe.

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Elon Musk

SpaceX shares targets and tentative launch date for Starship Flight 11

As with all SpaceX tests, the estimated timeline for Starship Flight 11 remains subject to change based on conditions and readiness.

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Credit: SpaceX

SpaceX is targeting Monday, October 13, for the eleventh test flight of its Starship launch system. The launch window is expected to open at 6:15 p.m. CT. 

Similar to past Starship missions, a live webcast will begin about 30 minutes before launch on SpaceX’s website, X account, and X TV app. As with all SpaceX tests, the estimated timeline for Starship Flight 11 remains subject to change based on conditions and readiness.

Super Heavy booster landing test

The upcoming mission will build on the data gathered from Starship’s tenth test flight, focusing on booster performance and upper-stage capabilities. The Super Heavy booster, previously flown on Flight 8, will launch with 24 flight-proven Raptor engines, according to SpaceX in a blog post on its official website. Its primary objective is to validate a new landing burn engine configuration designed for the next generation of Super Heavy.

Instead of returning to Starbase, the Super Heavy booster will follow a trajectory toward the Gulf of America. During descent, it will ignite 13 engines before transitioning to a five-engine divert phase and then completing the landing burn with three central engines, entering a full hover while still above the ocean surface, followed by shutdown and dropping into the Gulf of America.

Starship upper-stage experiments

The Starship upper stage for Flight 11 will carry out a series of in-space demonstrations, including the deployment of eight Starlink simulators that are comparable in size to next-generation Starlink satellites. These payloads will reenter and burn up during descent. A planned Raptor engine relight in orbit will also provide valuable test data.

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To evaluate the upper stage’s resilience during reentry, SpaceX engineers have intentionally removed heat shield tiles from select areas to stress-test Starship’s thermal protection system. The vehicle will attempt new maneuvers during descent, including a banking profile and subsonic guidance algorithms intended to simulate future return-to-launch-site missions. The upper stage will ultimately target a splashdown in the Indian Ocean.

SpaceX has already posted a link to the livestream for Starship Flight 11: 

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Astra CEO shades SpaceX over employee workload and Starbase

Elon Musk once stated that no one ever changed the world working just 40 hours a week.

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Credit: SpaceX

Elon Musk once stated that no one ever changed the world working just 40 hours a week. This was something that is openly known among his companies. They have the potential to change the world, but they require a lot of hours.

SpaceX’s working environment was recently criticized by Chris Kemp, the chief executive officer of Astra. During some remarks at the Berkeley Space Symposium 2025 earlier this month, Kemp shared some sharp remarks about the Elon Musk-led private space enterprise.

SpaceX working conditions and Starbase

As noted in a report from Ars Technica, Kemp discussed a variety of topics during his talk. These included Astra’s successes and failures, as well as his thoughts on other players in the spaceflight industry. To be fair to Kemp, he practically shaded every major rival, calling Firefly’s engine “garbage,” dubbing Blue Origin as slow, and stating that Rocket Lab’s Electron rocket is “too small.”

SpaceX also received some colorful words from the Astra CEO. According to Kemp, SpaceX is leading the way in the spaceflight industry and Elon Musk is admirable in the way that he is willing to fail in order to move quickly. He did, however, highlight that Astra offers a significantly better working environment than SpaceX.

“It’s more fun than SpaceX, because we’re not on the border of Mexico where they’ll chop your head off if you accidentally take a left turn. And you don’t have to live in a trailer. And we don’t make you work six and a half days a week, 12 hours a day. It’s appreciated if you do, but not required,” Kemp said.

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Elon Musk’s demands

It is known that Elon Musk demands quite a lot from his employees. However, it is also known that Musk-led companies move very fast and, in more ways than one, they have accomplished world-changing feats. Tesla, for example, has practically ushered in the era of the modern electric vehicle, and SpaceX has made space attainable through its reusable rockets. With this in mind, employees at Musk’s companies, and this of course includes SpaceX, are likely proud of their long work hours. 

No one could probably go to Mars in this lifetime with a team that really works just 40 hours a week, after all.

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