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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.

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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.

 

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.

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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!

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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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Elon Musk denies Starlink’s price cuts are due to Amazon Kuiper

“This has nothing to do with Kuiper, we’re just trying to make Starlink more affordable to a broader audience,” Musk wrote in a post on X.

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Credit: Starlink

Elon Musk has pushed back on claims that Starlink’s recent price reductions are tied to Amazon’s Kuiper project.

In a post on X, Musk responded directly to a report suggesting that Starlink was cutting prices and offering free hardware to partners ahead of a planned IPO and increased competition from Kuiper.

“This has nothing to do with Kuiper, we’re just trying to make Starlink more affordable to a broader audience,” Musk wrote in a post on X. “The lower the cost, the more Starlink can be used by people who don’t have much money, especially in the developing world.”

The speculation originated from a post summarizing a report from The Information, which ran with the headline “SpaceX’s Starlink Makes Land Grab as Amazon Threat Looms.” The report stated that SpaceX is aggressively cutting prices and giving free hardware to distribution partners, which was interpreted as a reaction to Amazon’s Kuiper’s upcoming rollout and possible IPO.

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In a way, Musk’s comments could be quite accurate considering Starlink’s current scale. The constellation currently has more than 9,700 satellites in operation today, making it by far the largest satellite broadband network in operation. It has also managed to grow its user base to 10 million active customers across more than 150 countries worldwide. 

Amazon’s Kuiper, by comparison, has launched approximately 211 satellites to date, as per data from SatelliteMap.Space, some of which were launched by SpaceX’s Falcon 9 rocket. Starlink surpassed that number in early January 2020, during the early buildout of its first-generation network.

Lower pricing also aligns with Starlink’s broader expansion strategy. SpaceX continues to deploy satellites at a rapid pace using Falcon 9, and future launches aboard Starship are expected to significantly accelerate the constellation’s growth. A larger network improves capacity and global coverage, which can support a broader customer base.

In that context, price reductions can be viewed as a way to match expanding supply with growing demand. Musk’s companies have historically used aggressive pricing strategies to drive adoption at scale, particularly when vertical integration allows costs to decline over time.

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SpaceX secures FAA approval for 44 annual Starship launches in Florida

The FAA’s environmental review covers up to 44 launches annually, along with 44 Super Heavy booster landings and 44 upper-stage landings.

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Credit: SpaceX

SpaceX has received environmental approval from the Federal Aviation Administration (FAA) to conduct up to 44 Starship-Super Heavy launches per year from Kennedy Space Center Launch Complex 39A in Florida. 

The decision allows the company to proceed with plans tied to its next-generation launch system and future satellite deployments.

The FAA’s environmental review covers up to 44 launches annually, along with 44 Super Heavy booster landings and 44 upper-stage landings. The approval concludes the agency’s public comment period and outlines required mitigation measures related to noise, emissions, wildlife, and airspace management.

Construction of Starship infrastructure at Launch Complex 39A is nearing completion. The site, previously used for Apollo and space shuttle missions, is transitioning to support Starship operations, as noted in a Florida Today report.

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If fully deployed across Kennedy Space Center and nearby Cape Canaveral Space Force Station, Starship activity on the Space Coast could exceed 120 launches annually, excluding tests. Separately, the U.S. Air Force has authorized repurposing Space Launch Complex 37 for potential additional Starship activity, pending further FAA airspace analysis.

The approval supports SpaceX’s long-term strategy, which includes deploying a large constellation of satellites intended to power space-based artificial intelligence data infrastructure. The company has previously indicated that expanded Starship capacity will be central to that effort.

The FAA review identified likely impacts from increased noise, nitrogen oxide emissions, and temporary airspace closures. Commercial flights may experience periodic delays during launch windows. The agency, however, determined these effects would be intermittent and manageable through scheduling, public notification, and worker safety protocols.

Wildlife protections are required under the approval, Florida Today noted. These include lighting controls to protect sea turtles, seasonal monitoring of scrub jays and beach mice, and restrictions on offshore landings to avoid coral reefs and right whale critical habitat. Recovery vessels must also carry trained observers to prevent collisions with protected marine species.

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Elon Musk reiterates rapid Starship V3 timeline with next launch in sight

Musk shared the update in a brief post on X, writing, “Starship flies again next month.”

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Credit: SpaceX/X

Elon Musk has confirmed that Starship will fly again next month, reiterating SpaceX’s aggressive timeline for the first launch of its Starship V3 rocket.

Musk shared the update in a brief post on X, writing, “Starship flies again next month.” The CEO’s post was accompanied by a video of Starship’s Super Heavy booster being successfully caught by a launch tower in Starbase, Texas. 

The timeline is notable. In late January, Musk stated that Starship’s next flight, Flight 12, was expected in about six weeks. This placed the expected mission date sometime in March. That estimate aligned with SpaceX’s earlier statement that Starship’s 12th flight test “remains targeted for the first quarter of 2026.”

If the vehicle does indeed fly next month, it would mark the debut of Starship V3, the upgraded platform expected to feature the rocket’s new Raptor V3 engines.

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Raptor V3 is designed to deliver significantly higher thrust than earlier versions while reducing cost and weight. Starship V3 itself is expected to be optimized for manufacturability, a critical step if SpaceX intends to scale production toward frequent launches for Starlink, lunar missions, and eventually Mars.

Starship V3 is widely viewed as the version that transitions the program from experimental testing to true operational scaling. Previous iterations have completed multiple integrated flight tests, with mixed outcomes but steady progress. Expectations are high that SpaceX is now working on Starship’s refinement.

An aggressive launch schedule supports several priorities at once. It advances Starlink’s next-generation satellite deployment, supports NASA’s lunar ambitions under Artemis, and keeps SpaceX on track for its longer-term Moon and Mars objectives.

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