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SpaceX Starship stacked with ballast for hop test debut

Starship SN4 has been outfitted with a ballast weight to enable its inaugural flight test. (NASASpaceflight - bocachicagal)

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SpaceX has installed a custom-built ballast atop its fourth full-scale Starship prototype, a sign that the company is rapidly approaching the ship’s first Starhopper-style hop test.

Although CEO Elon Musk officially “redirected” SpaceX’s resources away from Starship’s first flight and towards Crew Dragon’s NASA astronaut launch debut, the company continues to work around the clock to ready Starship SN4 for the program’s biggest test yet. Designed with the goal of creating a fully-reusable, ultra-capable launch vehicle that is unprecedentedly affordable, SpaceX’s Starship spacecraft and Super Heavy booster have made impressive progress over the last 12 or so months.

In July and August 2019, Starhopper – a low-fidelity testbed and proof of concept – successfully performed two untethered hop tests, ultimately flying more than 150m (~500 ft) above ground before safely touching down. Three months later, the first full-scale Starship prototype was destroyed almost immediately after its first pressure test began, a failure that lead SpaceX to expedite factory upgrades. Just six months later, SpaceX has completed multiple successful tests, including pressure tests that pushed beyond the pressures needed for safe human spaceflight, several full wet dress rehearsals (WDRs) with live propellant, and three Raptor engine static fires. In fewer words, Starship is ready for its next big test: flight.

SpaceX technicians prepare to complete a jerryrigged ballast weight for Starship SN4. (NASASpaceflight – bocachicagal)

However, Starship SN4 currently has just one Raptor engine installed and will remain in that configuration for its inaugural hop, expected to reach a maximum altitude identical to Starhopper (150m/500ft). The odd configuration means that the rocket will be propelled by asymmetric thrust, as Starship’s ‘thrust puck’ engine section is designed to hold three Raptor engines in a triangular formation. Raptor is capable of producing up to 200 metric tons (~440,000 lbf) of thrust with an unclear level of throttle control (likely mediocre according to comments made by Elon Musk).

Impressively, although it might seem reasonable to assume that Starship SN4 is about as heavy as the ~120 ton Starhopper, the clear and present need to install substantial ballast suggests otherwise. Combined with comments made during SN4’s April 2020 transport from factory to launch site, it appears that even SpaceX’s early Starship engine sections weigh just 50-60 metric tons (110,000-125,000 lb) empty. That weight doesn’t account for the flaps, heat shield, nose section, or many other heavy components that orbital Starships will eventually need but is still impressive.

Starship SN4 was transported to the launch pad on April 23rd. (NASASpaceflight – bocachicagal)
On May 27th, SpaceX installed a massive ballast weight on top of the Starship prototype. (NASASpaceflight – bocachicagal)

That impressive weight reduction, Raptor’s inability to safely throttle low, and the FAA’s lack of interest in dozens (up to hundreds) of tons of explosive propellant flying above or around populated areas poses its own challenges for the first full-scale Starship flight. The addition of ballast helpfully solves (or at least alleviates) several of those issues. Notably, ballast can prevent SpaceX from having to fuel Starship SN4 with dozens of extra tons of explosive propellant to counteract the high thrust of its single engine and permit a safe launch and landing.

At the same time, if Starship SN4’s wet weight is reduced by carrying less propellant during its first flight, that actually exacerbates the problem of Raptor’s small throttle range, as a lighter ship would be much harder to manage as the engine rapidly burns propellant and thus loses mass. With ballast, Raptor won’t have to throttle as low as it would otherwise have to to ensure a gentle rate of deceleration. Built out of sheet steel and two spare rolls of the same steel used to form Starship rings, Starship SN4’s new ballast likely increases its dry mass by some 50% or more (25+ metric tons).

(NASASpaceflight – bocachicagal)
Starship SN4’s solid steel ballast. (NASASpaceflight – bocachicagal)

Pending Crew Dragon’s inaugural astronaut launch, now scheduled no earlier than 3:22 pm EDT (19:22 UTC), May 30th after weather delayed the first May 27th launch attempt, Starship SN4 has no testing periods on the calendar at the moment. Speaking around May 23rd, Musk stated that the ship was likely at least a “few weeks” away from its flight debut, suggesting that the ship will perform another static fire test to prepare for its first hop as early as next week. Stay tuned for updates as SpaceX’s works towards two very exciting Crew Dragon and Starship milestones.

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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 Robotaxi riders will face the best dilemma when booking a ride

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Credit: Joe Tegtmeyer | X

Tesla has updated its Robotaxi app so riders can pick which vehicle they want before they book. The latest in-app screens now show two options side by side: the two-seat Cybercab and the four-seat Model Y.

A screenshot circulating Thursday shows the change in practice. In Austin, a rider could choose a gold Cybercab for two people or a Model Y for four. Tesla’s updated description calls Cybercab “our first purpose-built autonomous vehicle,” designed for safety, accessibility, and comfort, and says the lineup is available only through the Robotaxi app.

The distinction is more than cosmetic, and it’s important to note that Robotaxi refers to the platform, while Cybercab refers to a vehicle.

Model Y Robotaxis have carried the service since it opened in Austin in mid-2025 and later expanded to Dallas, Houston, and parts of Florida. Those vehicles are converted production SUVs that still have steering wheels and pedals.

Cybercab is different. It has no driver controls, butterfly doors, a low seat height meant to work with wheelchairs, extra trunk space for assistive devices, and braille on the handles. Tesla has registered dozens of the two-seaters with Texas regulators in the days leading up to its September 3 Austin event.

Giving riders a choice lets Tesla match the vehicle to the trip. Most rides involve one or two people, which is where Cybercab is meant to be cheaper and more efficient to operate. Groups of three or four, or anyone who needs more space, can still request a Model Y.

The same app handles booking, payment, cabin settings, and, on Cybercab, features such as phone-based door opening and in-cabin voice controls.

Tesla Cybercab event gains steam ahead of massive launch

The update does not mean every city suddenly has both cars available. Cybercab support is listed for Austin first, and the purpose-built fleet is still small compared with the existing Model Y roster. Even so, the app change marks a shift from a single-vehicle pilot to a mixed fleet.

Riders can now choose between the compact, purpose-built robotaxi and the familiar SUV that launched the service.

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Tesla Cybercab sightings broaden well outside of Austin with autonomy in focus

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Credit: Tesla Robotaxi | X

Tesla Cybercab sightings are broadening far and wide, well outside of downtown Austin, Texas, with autonomy in focus as the company plans to launch the all-electric, two-seater this evening in the Lone Star State.

Tesla is set to launch Cybercab to a small group of people this evening in a dedicated event in Austin, Texas. Public details on the event are relatively slim.

However, Tesla’s focus on Cybercab falls well outside of the downtown Austin area and is expanding well across the United States as things continue to move quickly with the company’s autonomous efforts in 2026. Today, various images of Cybercab fleets in interesting locations have started to circulate.

The most notable is a fleet of at least 20 Cybercabs at Miami International Airport in Florida. Spotted last night, the fleet is expansive and is indicative of a looming release of Cybercabs once regulatory boxes are checked off.

Tesla has already been operating the Robotaxi platform in Miami for several months, but this Cybercab fleet at the airport could be joining the ride-hailing platform as approvals arrive:

Another fleet of Cybercabs was spotted at the Devon, PA showroom just outside of Philadelphia. We have seen several Cybercab units testing around the Philadelphia Metro Area, which is interesting considering Tesla does not have any active Robotaxi geofence in Pennsylvania.

Philadelphia would be an ideal location to test ride-hailing due to its dense tourist population, large, sprawling city layout, and to compete with other ride-hailing companies that operate in the city.

Expansive fleets of Cybercabs will be popping up in and around major cities throughout the rest of the year, if we were betting on it. Tesla has made it obvious that the Cybercab rollout will be aggressive and fast-paced, but within reason. Tesla is still prioritizing safety, so these testing phases will likely go on for some period of time before more members of the public are able to snag a Cybercab for a personal chariot.

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Tesla Model Y L gets suspension complaints in over odd issue China

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Credit: @TeslaNewswire/X

The Tesla Model Y L is arguably the most hyped trim of the all-electric crossover, other than the Performance configuration that comes with white-knuckle speed and sports car-level handling.

However, it is not all perfect. Tesla owners in China who took delivery of the Model Y L, denoted with an L to highlight its longer wheelbase, are experiencing what they are referring to as “collapsing” of the rear wheels, as suspension issues appear to be an issue with some of the builds.

The gap between the wheel arch and tire has narrowed to the point that “not even a single finger” could fit, according to a report from Car News China. The failures are not tied to a specific mileage, as one owner said that after just 9,000 kilometers (5,600 miles), they noticed the suspension issue when their car was fully loaded.

Another one had the issue at 30,000 kilometers (18,640 miles) and noticed that the wheel gap shrank to two fingers, so not as drastic as the person who reported a similar issue at 9,000 km.

Tesla Model Y L is gaining momentum in China’s premium segment

Along with the visual recognition of the issue, others are saying the sagging is causing abnormal wear on the inside of the tires. Extra weight and instant torque already provide additional stress on the tires in electric vehicles during normal operation, so it is no surprise that this is another complaint.

There has been no recall issued by Tesla, and the company has not yet publicly acknowledged the issue.

Some are suggesting that owners use a “finger test” to self-diagnose whether there is an issue with the suspension. There should be four fingers between the tire and the wheel well; anything less than that starts to get dicey.

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