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SpaceX wiggles Starhopper’s Raptor engine, tests parts ahead of hover test debut

Repeating a test conducted in June with Raptor SN04, SpaceX tested Starhopper and Raptor SN06's thrust vectoring capabilities on July 12th. (NASASpaceflight - bocachicagal)

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On the evening of July 12th, SpaceX technicians put Starhopper’s freshly-installed Raptor – serial number 06 (SN06) – through a simple but decidedly entertaining test, effectively wiggling the engine in circles.

Designed to verify that Raptor’s thrust vectoring capabilities are in order and ensure that Starhopper and the engine are properly communicating, the wiggle test is a small but critical part of pre-flight acceptance and a good indicator that the low-fidelity Starship prototype is nearing its first hover test(s). Roughly 48 hours after a successful series of wiggles, Starhopper and Raptor proceeded into the next stage of pre-flight acceptance, likely the final more step before a tethered static fire.

Routine for all Falcon rockets, SpaceX’s exceptionally rigorous practice of static firing all hardware at least once (and often several times) before launch has unsurprisingly held firm as the company proceeds towards integrated Starhopper and Starship flight tests. Despite the fact that Raptor SN06 completed a static fire as recently July 10th, SpaceX will very likely put Starhopper and its newly-installed Raptor through yet another pre-flight static fire, perhaps its fourth or fifth test this month.

Although it would undoubtedly be easier, cheaper, and faster to skip that post-delivery static fire, it will simultaneously lower the risk of Raptor failing mid-flight and verify that Starhopper itself is healthy and ready for untethered hovering. Although SpaceX could likely live without Starhopper in the event that it’s lost during flight-testing, any failure capable of destroying the vehicle itself is at least as capable of severely damaging or completely destroying the spartan but still expansive test and launch facilities the company built over the course of several months.

SpaceX has been hard at work gradually building, expanding, and upgrading its South Texas launch facilities since December 2018. (NASASpaceflight – bocachicagal, 04/27/2019)

Would you like some testing with your testing?

Follow July 12th’s nighttime Raptor wiggle test, July 13th was mainly quiet and filled with inspections of Starhopper, Raptor, and other various work. The day after, however, SpaceX proceeded through several hours of propellant loading, ending with what looked like less energetic versions of the Raptor preburner ignition tests Starhopper previously performed with Raptor SN02.

In a staged-combustion engine like Raptor, getting from the supercool liquid oxygen and methane propellant to 200+ tons of thrust is quite literally staged, meaning that the ignition doesn’t happen all at once. Rather, the preburners – essentially their own, unique combustion chambers – ignite an oxygen- or methane-rich mixture, the burning of which produces the gas and pressure that powers the turbines that bring fuel into the main combustion chamber. That fuel then ignites, producing thrust as they exit the engine’s bell-shaped nozzle.

The first obvious test occurred around 7:30pm CT, July 14th. (LabPadre)
The second obvious test followed around 8:50 pm CT. (LabPadre)

Although the fireworks are so subtle that they are easily missed, the conditions inside the preburner – hidden away from view – are actually far more intense than the iconic blue, purple, and pink flame that exists Raptor’s nozzle. This is because the preburners have to nurture the conditions necessary for the pumps they power to fuel the main combustion chamber. Much like hot water will cool while traveling through pipes, the superheated gaseous propellant that Raptor ignites to produce thrust will also cool (and thus lose pressure) as it travels from Raptor’s preburner to the main combustion chamber.

Thus, if the head pressure produced in the preburners is too low, Raptor’s thrust will be (roughly speaking) proportionally limited at best. At worst, low pressure in the preburners can completely prevent Raptor from starting and running stably and can even trigger a “hard start” or shutdown that could damage or destroy the engine. As such, to preburners fundamentally have to operate at higher chamber pressures (and thus higher temperatures) than the main combustion chamber (the big firey bit at the end). According to Elon Musk, Raptor’s oxygen preburner has the worst of it, operating at pressures as high or higher than 800 bar (11,600 psi, 80 megapascals).

Coincidentally, this is roughly equivalent to the pressure at the bottom of the Pacific Ocean.

Starhopper and Raptor seen on the afternoon of July 14th, preparing for an evening of testing. (NASASpaceflight – bocachicagal)

In short, preburner testing is no less critical than full-on static fire testing with an engine like Raptor. July 14th’s test was also made doubly efficient due to the fact that preburner testing requires liquid propellant, which effectively makes the whole test a wet dress rehearsal (WDR) even before any engine ignition or partial ignition is involved. Per SpaceX moving from propellant loading to preburner/turbine testing, Starhopper is almost certainly healthy and operating as expected, an excellent sign that the ungainly vessel may be ready for a static fire of Raptor as early as 2pm CT, July 15th.

The memes, oh, the memes.

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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 hints at when Tesla could reduce Safety Monitors from Robotaxi

Tesla could be reducing Safety Monitors from Robotaxi within ‘a month or two,’ CEO Elon Musk says.

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Credit: Joe Tegtmeyer | X

Elon Musk hinted at when Tesla could begin reducing Safety Monitors from its Robotaxis. Safety Monitors are Tesla employees who sit in the front passenger seat during the driverless rides, and are there to ensure safety for occupants during the earliest rides.

Tesla launched its Robotaxi fleet in Austin last Sunday, and after eight days, videos and reviews from those who have ridden in the driverless vehicles have shown that the suite is safe, accurate, and well coordinated. However, there have been a few hiccups, but nothing that has put anyone’s safety in danger.

A vast majority — close to all of the rides — at least according to those who have ridden in the Robotaxi, have been performed without any real need for human intervention. We reported on what was the first intervention last week, as a Safety Monitor had to step in and stop the vehicle in a strange interaction with a UPS truck.

Watch the first true Tesla Robotaxi intervention by safety monitor

The Tesla and UPS delivery truck were going for the same street parking space, and the Tesla began to turn into it. The UPS driver parallel parked into the spot, which was much smaller than his truck. It seemed to be more of an instance of human error instead of the Robotaxi making the wrong move. This is something that the driverless cars will have to deal with because humans are aggressive and sometimes make moves they should not.

The Safety Monitors have not been too active in the vehicles. After all, we’ve only seen that single instance of an intervention. There was also an issue with the sun, when the Tesla braked abnormally due to the glare, but this was an instance where the car handled the scenario and proceeded normally.

With the Robotaxi fleet operating impressively, some are wondering when Tesla will begin scaling back both the Safety Monitors and Teleoperators that it is using to ensure safety with these early rides.

CEO Elon Musk answered the inquiry by stating, “As soon as we feel it is safe to do so. Probably within a month or two.”

Musk’s response seems to confirm that there will be fewer Teleoperators and Safety Monitors in the coming months, but there will still be some within the fleet to ensure safety. Eventually, that number will get to zero.

Reaching a point where Tesla’s Robotaxi is driverless will be another significant milestone for the company and its path to fully autonomous ride-sharing.

Eventually, Tesla will roll out these capabilities to consumer-owned vehicles, offering them a path to generate revenue as their car operates autonomously and completes rides.

For now, Tesla is focusing on perfecting the area of Austin where it is currently offering driverless rides for just $4.20 to a small group of people.

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Tesla sees explosive sales growth in UK, Spain, and Netherlands in June

In countries like the UK, Spain, and the Netherlands, Tesla’s June sales surged significantly compared to May.

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Credit: Tesla Europe & Middle East/X

After months of declining deliveries and market pressure, Tesla appears to be regaining its footing in Europe. Tesla saw a significant spike in electric vehicle registrations across several key markets in June, signaling renewed momentum for the EV maker.

In countries like the UK, Spain, and the Netherlands, Tesla’s June sales surged significantly compared to May.

Explosive growth in the UK, Spain, and the Netherlands

Tesla’s most notable performance came in the United Kingdom, where June registrations jumped 224% month-over-month, and Spain, where registrations more than tripled. This made Tesla the top-selling electric car brand for the month in both countries, as per a CarUp report.

The Netherlands saw Tesla become the best-selling car brand in June across all vehicle segments. Tesla’s continued success in Norway also appears to be holding steady, though full figures for the market have not yet been finalized.

These numbers suggest Tesla’s European sales slump may have been temporary, with strong demand returning amid the ramp of the new Model Y, which was largely unavailable in the first quarter. 

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Mixed results in Sweden but signs of progress

In Sweden, Tesla’s performance remained mixed in June. While year-over-year registrations dropped over 70% in June, the company’s market share jumped 72% compared to May. Tesla now holds an 8.6% market share in the Swedish EV market, which means that one in every twelve new electric vehicles registered in the country last month was a Tesla, as per data compiled by eu-evs.com.

So far in 2025, Tesla ranks as the fourth-largest EV brand in Sweden, with 3,461 vehicles registered, trailing Volkswagen, Volvo, and Kia. The Tesla Model Y has remained a strong seller, ranking as the third most registered electric vehicle this year, behind the Volkswagen ID.7 and Volvo XC40, despite being largely absent in Q1 2025.

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Xiaomi CEO congratulates Tesla on first FSD delivery: “We have to continue learning!”

Xiaomi has become one of Tesla’s strongest rivals in China.

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Credit: Tesla/X

Just days after unveiling the Xiaomi YU7, a vehicle that is considered as the Model Y’s strongest competitor yet, Xiaomi CEO Lei Jun gave a nod of respect to Tesla and its Full Self-Driving (FSD) program. 

In a post on Weibo, Lei Jun highlighted the remarkable nature of Tesla’s first autonomous delivery. He also acknowledged that Xiaomi still has much to learn in the electric vehicle industry.

Xiaomi CEO’s Nod of Respect

Lei Jun’s comments about Tesla’s FSD delivery were shared as a response to Tesla VP Grace Tao’s post about the recent feat. The Tesla VP shared several key aspects of the delivery, from the fact that there was no driver in the Model Y to the vehicle reaching over 70 mph as it drove to its owner. 

“For the first time in history, the vehicle was delivered to the owner by itself. There was no driver or remote control throughout the journey, and the maximum speed reached 115 kilometers per hour, and it arrived safely at the customer’s door. This is a brand new Model Y. Tesla always surpasses imagination with disruptive innovation. A new era, exciting!” Tao wrote in her post.

In his response, the Xiaomi CEO acknowledged Tesla’s incredible feat. “Tesla is indeed amazing, leading the industry trends in many areas, especially FSD. We still have to continue learning!” he wrote.

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Xiaomi’s Recent Tesla Competitor

The Xiaomi CEO’s comments show that Tesla’s projects and leadership garner a lot of respect in the global electric vehicle sector. While Tesla and Elon Musk tend to be media punching bags in the United States and Europe, the company and its CEO seem to be taken very seriously in China. This was despite China being the world’s most competitive electric vehicle market.

Xiaomi itself has become one of Tesla’s strongest rivals in China, with its first car, the SU7, bringing the fight to the Tesla Model 3. Its most recent vehicle, the YU7, could very well be the Model Y’s most legitimate rival yet, as it is more affordable, bigger, and more feature-laden than Tesla’s best-selling crossover. The YU7 has garnered quite a lot of attention, with Xiaomi receiving 200,000 firm orders for the vehicle within the first three minutes of its launch.

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