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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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SpaceX to expand Central Texas facility with $8M Bastrop project

Bastrop is already the site of several Elon Musk-led ventures.

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Credit: SpaceX

SpaceX is set to expand its presence in Central Texas with an $8 million project to enlarge its Bastrop facility, as per state filings. 

The 80,000-square-foot addition, which is scheduled to begin construction on September 24 and wrap in early January 2026, was registered with the Texas Department of Licensing and Regulation and initially reported by My San Antonio

New investment

Bastrop is already the site of several Elon Musk-led ventures. The upcoming expansion will extend SpaceX’s office at 858 FM 1209, near Starlink’s operations and The Boring Company’s facilities. Just down the road, X is housed in the Hyperloop Plaza at 865 FM 1209.

SpaceX’s expansion reflects a steady buildup of resources in Bastrop since the private space firm established its presence in the area. The addition was praised by Tesla Governor Greg Abbott, who wrote on X that the expansion will “bring more jobs, innovations and will strengthen Starlink’s impact worldwide.” 

State support

In March, Gov. Greg Abbott announced a $17.3 million state grant to SpaceX for an “expansion of their semiconductor research and development (R&D) and advanced packaging facility in Bastrop.” The project is expected to create more than 400 new jobs and generate over $280 million in capital investment.

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Following the grant award, the Texas Governor also noted that SpaceX’s facility would be growing by 1 million square feet across three years to boost its Starlink program. SpaceX’s Starlink division is among the company’s fastest-growing segments, with the satellite internet system connecting over 6 million users and counting worldwide. 

Recent reports have also indicated that Starlink has struck a deal with EchoStar to acquire 50 MHz of exclusive S-band spectrum in the United States and global Mobile Satellite Service (MSS) licenses. This should pave the way for Starlink to provide 5G coverage worldwide, even in remote areas. 

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Starlink’s EchoStar spectrum deal could bring 5G coverage anywhere

The agreement strengthens Starlink’s ability to expand its mobile coverage worldwide.

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Credit: SpaceX/X

SpaceX has struck a deal with EchoStar to acquire 50 MHz of exclusive S-band spectrum in the United States and global Mobile Satellite Service (MSS) licenses, paving the way for its next-generation Starlink Direct to Cell constellation. 

The agreement strengthens Starlink’s ability to expand its mobile coverage worldwide. With the upgraded system, SpaceX aims to deliver full 5G connectivity to unmodified cell phones and eliminate mobile dead zones worldwide.

Expanding mobile coverage

Starlink’s Direct to Cell service was first launched in early 2024 with satellites designed to connect directly to standard LTE mobile devices. Within days of deployment, engineers demonstrated texting from unmodified phones, followed by video calling. Over the past 18 months, SpaceX has grown the system to more than 600 satellites, which now offer service across five continents. Today, Starlink Direct to Cell is considered the largest 4G coverage provider worldwide, connecting over 6 million users and counting, according to SpaceX in a post.

The constellation integrates with Starlink’s broader fleet of 8,000 satellites via a laser mesh network. Operating at 360 kilometers (224 miles) above Earth, the satellites connect directly to devices without hardware or firmware modifications. The system is already supporting messaging, video calls, navigation, social media apps, and IoT connectivity in remote areas.

Next-generation system

Through its new EchoStar spectrum acquisition, SpaceX plans to develop a second-generation constellation with far greater capacity. The upgraded satellites will leverage SpaceX-designed silicon and advanced phased array antennas to increase throughput by 20x per satellite and increase total system capacity by more than 100x. These enhancements are expected to support full 5G cellular connectivity in remote areas, with performance comparable to terrestrial LTE networks.

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Partnerships with major mobile carriers remain central to Starlink’s expansion. Operators including T-Mobile in the United States, Rogers in Canada, KDDI in Japan, and Kyivstar in Ukraine are integrating Direct to Cell services for coverage in rural areas and during emergencies. The service has already provided critical communication during hurricanes, floods, and wildfires, enabling millions of SMS messages and emergency alerts to be delivered when ground networks were unavailable.

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SpaceX Starship launches face pushback in Florida over noise, flights—and nudists

SpaceX is seeking permission to fly its fully reusable Starship system from Launch Complex 39A.

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Credit: SpaceX

The Federal Aviation Administration (FAA) has wrapped up a series of public hearings on SpaceX’s proposal to launch its Super Heavy Starship rocket from NASA’s Kennedy Space Center (KSC). 

The sessions, held both in-person and online, form part of the draft environmental impact statement (EIS) review that will determine whether SpaceX would be cleared to conduct Starship launches and landings from Florida’s Space Coast.

FAA review and Starship launch plans

According to the FAA’s draft EIS, SpaceX seeks permission to fly its fully reusable Starship system from Launch Complex 39A, where construction of a dedicated tower and infrastructure has already begun. Proposed operations could involve landings at KSC or droneships positioned across the Atlantic, Pacific, and Indian Oceans. The FAA emphasized that final approval is not guaranteed with the completion of the EIS, as safety and financial requirements must still be met, as noted in a Space.com report.

Starship’s larger scale compared to Falcon 9 means expanded exclusion zones for air, sea, and beach access. The analysis also projected more than 60 annual closures of Playalinda Beach, alongside potential flight delays across Florida airports lasting 40 minutes to two hours. Port Canaveral would also be affected by maritime restrictions.

Local concerns

Public comments reflected a mix of optimism and unease. Aviation officials, such as Tampa International Airport COO John Tiliacos, warned of significant disruption to commercial flights. “There is the potential that there’s going to be significant impact to commercial aviation and the traveling public. That’s something that certainly the FAA needs to give consideration to and, frankly, come up with a plan to mitigate,” he stated. 

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Others raised health concerns, noting that chronic sleep disruption from launch noise could impact veterans and trauma survivors. Robyn Memphis, a neuroscience and psychology graduate student, stated that sleep disruptions from launch noise and sonic booms could carry lasting effects. “Chronic sleep disruption is not just inconvenient. This is directly linked to depression, anxiety… cardiovascular disease, even suicide risk. And being in Florida, we have many veterans and trauma survivors in the community,” she said.

Nudist protests and responses

Erich Schuttauf, the executive director of the American Association for Nude Recreation, also argued that places like Playalinda Beach, a nudist beach, are crucial for people who travel to places where public nudity is legal. His sentiments were echoed by fellow nudist Sue Stevens, who noted that “It’s probably a quarter million people that travel and think like I do, who look for destinations that are beautiful and surrounded by like-minded people.”

Photographer Max West, who plans to move to Florida to photograph Starship, noted that the spacecraft presents a notable step forward for humanity. And while its impact to communities is not marginal, the progress it offers is well worth it. “I’m not going to say that there is zero environmental impact there,” he said, though he also stated that there has to be some “little sacrifices along the way. “The turtles and the nudists will have to migrate. That’s the cost that you have to pay for this incredible stuff that’s happening.”

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