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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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Tesla receives major institutional boost with Nomura’s rising stake

The move makes Tesla Nomura’s 10th-largest holding at about 1% of its entire portfolio.

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Credit: Tesla China

Tesla (NASDAQ:TSLA) has gained fresh institutional support, with Nomura Asset Management expanding its position in the automaker. 

Nomura boosted its Tesla holdings by 4.2%, adding 47,674 shares and bringing its total position to more than 1.17 million shares valued at roughly $373.6 million. The move makes Tesla Nomura’s 10th-largest holding at about 1% of its entire portfolio.

Institutional investors and TSLA

Nomura’s filing was released alongside several other fund updates. Brighton Jones LLC boosted its holdings by 11.8%, as noted in a MarketBeat report, and Revolve Wealth Partners lifted its TSLA position by 21.2%. Bison Wealth increased its Tesla stake by 52.2%, AMG National Trust Bank increased its position in shares of Tesla by 11.8%, and FAS Wealth Partners increased its TSLA holdings by 22.1%. About 66% of all outstanding Tesla shares are now owned by institutional investors.

The buying comes shortly after Tesla reported better-than-expected quarterly earnings, posting $0.50 per share compared with the $0.48 consensus. Revenue reached $28.10 billion, topping Wall Street’s $24.98 billion estimate. Despite the earnings beat, Tesla continues to trade at a steep premium relative to peers, with a market cap hovering around $1.34 trillion and a price-to-earnings ratio near 270.

Recent insider sales

Some Tesla insiders have sold stock as of late. CFO Vaibhav Taneja sold 2,606 shares in early September for just over $918,000, reducing his personal stake by about 21%. Director James R. Murdoch executed a far larger sale, offloading 120,000 shares for roughly $42 million and trimming his holdings by nearly 15%. Over the past three months, Tesla insiders have collectively sold 202,606 shares valued at approximately $75.6 million, as per SEC disclosures.

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Tesla is currently entering its next phase of growth, and if it is successful, it could very well become the world’s most valuable company as a result. The company has several high-profile projects expected to be rolled out in the coming years, including Optimus, the humanoid robot, and the Cybercab, an autonomous two-seater with the potential to change the face of roads across the globe.

@teslarati Tesla Full Self-Driving yields for pedestrians while human drivers do not…the future is here! #tesla #teslafsd #fullselfdriving ♬ 2 Little 2 Late – Levi & Mario
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Tesla rolls out fresh Supercharger pricing strategy to more locations

Live Pricing aimed to resolve some of the shortcomings of the off-peak and on-peak system, aiming to keep prices low and base them on current utilization instead of a set time when prices change.

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tesla supercharger
Credit: Tesla

Tesla has rolled out a fresh Supercharger pricing strategy to more locations, as it confirmed it has added 550 additional sites in the United States to its “Live Pricing” strategy.

Live Pricing for Superchargers launched back in May, and was the company’s latest strategy to keep charging your EV cheap, affordable, and easy to understand.

Tesla has adjusted its pricing strategy at Superchargers several times over the past few years, with the most notable being the 2020 introduction of off-peak and on-peak Supercharging rates.

Live Pricing aimed to resolve some of the shortcomings of the off-peak and on-peak system, aiming to keep prices low and base them on current utilization instead of a set time when prices change.

Tesla explained the program when it launched:

“We are piloting on-peak and off-peak pricing based on live Supercharger utilization rather than estimations. The average price remains unchanged, but this live feedback loop improves accuracy. This corrects off-peak pricing during times of congestion, or on-peak pricing when Superchargers are plentiful. You’ll always see the price before your session begins, and prices do not change mid-session. A small-scale pilot is launching at 10 sites and will expand based on feedback and success.”

The initial rollout only included Superchargers in California, but it was not all of them, only a handful instead. Tesla was attempting to launch it in a very controlled manner by using a Pilot Program that would iron out all the early bugs and potential issues it might run into.

However, the company expanded the program by launching it at an additional 550 sites in California, New Jersey, New York, Florida, and Illinois:

The price you pay is locked in when you plug in, so if the Supercharger station you are charging at becomes more crowded and the program bumps up the rates because of high utilization rates, you will still receive the cheaper price that was enabled when you arrived.

@teslarati With a pedestrian in the crosswalk, Tesla Full Self-Driving shows off its courtesy. Human drivers? Not so much. #tesla #teslafsd #fullselfdriving ♬ AMERICAN HEART – Maxwell Luke

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Tesla Robotaxi was just spotted in a new state for the first time

The company is still attempting to expand and has explicitly stated that it plans to offer rides in Nevada, Arizona, and Florida in the near future. However, a pair of Robotaxi mules, fitted with LiDAR equipment for ground truth validation, was spotted in a new region for the first time.

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Credit: Tesla

Tesla Robotaxi mules were spotted in a new state for the first time as the company plans to expand the ride-sharing service to new areas of the United States in the coming months.

Tesla is offering Robotaxi rides in Austin already, where nobody is present in the driver’s seat except for on freeway routes. In California, Tesla refers to its platform as a ride-hailing suite, and a “Safety Monitor” is present in the driver’s seat at all times, but the vehicle operates on Full Self-Driving.

The company is still attempting to expand and has explicitly stated that it plans to offer rides in Nevada, Arizona, and Florida in the near future. However, a pair of Robotaxi mules, fitted with LiDAR equipment for ground truth validation, was spotted in a new region for the first time.

Over the weekend, Tesla Robotaxi mules were spotted in Enola, Pennsylvania, just about ten minutes from downtown Harrisburg:

Enola is situated to the northwest of Harrisburg, Pennsylvania’s State Capitol. Interestingly, you’d expect Tesla to be testing these types of vehicles in other, more populated areas; Philadelphia is about two hours East, and Pittsburgh is about three hours west. State College is about an hour North of Enola.

Looking at the location of where the vehicles were spotted tells an interesting story, as Enola, located right outside of the State Capitol, could be a move to nudge legislators to consider looking at some of the laws that deal with driverless and autonomous vehicle operation.

Pennsylvania’s Act 130 of 2022 and subsequent guidelines permit the testing of driverless vehicles in the Commonwealth, but PennDOT requires a permit from Tesla or any other company that wants to operate a ride-hailing service in PA.

It’s also important to note that the cars could have simply been stopping through, as they were spotted at a Supercharger location along Interstate 81, which spans from Tennessee to New York.

It is not to say the vehicles are testing along the entire route, but likely a segment of it. The fact that they were spotted in Pennsylvania does bode well for Tesla’s expansion efforts moving forward.

@teslarati Tesla Full Self-Driving yields for pedestrians while human drivers do not…the future is here! #tesla #teslafsd #fullselfdriving ♬ 2 Little 2 Late – Levi & Mario

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