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SpaceX’s odd Starbase propellant storage tank prototype passes first test

A prototype of SpaceX's custom-built Starbase propellant storage tanks appears to have passed its first test without issue. (NASASpaceflight - bocachicagal)

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Likely to the relief of many, SpaceX appears to have successfully tested a prototype of the custom-built Starbase propellant storage tanks that will eventually hold thousands of tons of fuel and oxidizer.

For reasons unknown, SpaceX’s built its first ground support equipment (GSE) ‘test tank’ – a subscale prototype designed to quickly verify basic production quality and design goals – months after it began mass-producing operational storage tanks. In fact, of the seven total GSE tanks expected to be built, SpaceX has already completed seven, installed five, and scrapped one. Known as GSE4, SpaceX actually used modified parts of that scrapped tank to assemble the GSE test tank that first rolled to Starbase’s launch (and test) facilities on August 23rd.

Two days later, SpaceX subjected the small tank to its first test.

Given that SpaceX appears to have almost retroactively assembled the GSE4 test tank after building the final products, the results from its testing were always going to be significantly more anxiety-inducing than any of the more than half-dozen other tanks the company has tested in the last year and a half. Having already fabricated, assembled, or even installed six of seven planned GSE tanks, the discovery of major issues during testing could potentially cause months of delays by forcing SpaceX to perform lengthy repairs or even fully scrap all six existing tanks and start over.

SpaceX has built itself a farm of propellant storage tanks that are almost identical to the tanks used on Starships and Super Heavy boosters. (NASASpaceflight – bocachicagal)

Thankfully, at least for the time being, it appears that SpaceX can write off those potential worst-case scenarios. On August 25th, SpaceX took advantage of a test window initially believed to be for Starship S20 and put the cobbled-together GSE4 tank through its paces for the first time. As with previous test tanks, all SpaceX can really do is fill the prototype with liquid nitrogen (LN2), a non-flammable alternative to liquid oxygen or methane propellant that is approximately as cold and heavy. As a storage tank prototype, though, GSE4 has no need for hydraulic ram setups used to simulate the thrust of Raptor engines on several previous prototypes.

As such, one or several cryogenic proof tests were all that were ever really in GSE4’s future. On GSE4’s first test, SpaceX performed a more or less normal cryogenic proof, completely filling the tank with LN2, closing its vents, and then allowing the natural process of LN2 boiloff to raise the tank to the desired test pressure. However, unlike other test tanks, GSE4 never actually appeared to reopen its main vents. In fact, SpaceX may have never actually drained liquid nitrogen from the test tank, instead simply letting it slowly warm up and boil off into gas that was seemingly managed and vented by ground systems instead of the tank itself.

GSE4’s testing was more reminiscent of Starship test tank SN2 than anything.

As a result, GSE4 stayed frosty (indicating a significant amount of remaining liquid nitrogen) for more than eight hours, strongly implying that it was either very slowly drained or simply allowed to warm up naturally. Given that large cryogenic storage tanks really don’t have to be significantly pressurized to complete their job, it’s possible that GSE4’s first test was primarily meant to verify the basic structural integrity of a tank that’s slightly different than those on Starship and, more importantly, test a different method of pressure and fluid management where most of that work is done by external, permanent systems on the ground.

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That’s exactly what one might expect of rocket tankage slightly modified to serve as ground storage tanks. SpaceX’s GSE tanks never have to act as self-contained units and can instead rely almost entirely on separate systems.

A GSE tank is ‘sleeved.’ (NASASpaceflight – bocachicagal)

Aside from verifying that that slightly different method of tank operations works as expected, GSE4’s first test likely also allowed SpaceX to better characterize the thermal properties of the thin steel skin and domes that are Starship and GSE tanks. Unlike GSE4, operational GSE tanks will be enclosed inside 12m (~40 ft) wide ‘cryo shells’ designed to insulate their cryogenic contents, but the insulative properties of the inner tanks (or the lack there of, rather) will still determine how well that insulation works and how much is actually needed to reach the desired boiloff rates. A contractor hired by SpaceX has already completed all seven cryo shells, so any results gathered from GSE4 will obviously be more of a check than a developmental test, but data is still data.

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’s Roadster appearance at SpaceX has merger watchers talking

Tesla’s next generation Roadster was spotted at SpaceX’s Hawthorne headquarters, two weeks after its unveiling.

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The Roadster’s rear wing, one of the aerodynamic elements Tesla pairs with a fan-based downforce system. (Image: Tesla)

Tesla’s next generation Roadster turned up at SpaceX’s headquarters in Hawthorne, California on Wednesday, less than two weeks after the car flew off a ramp at its unveiling in Texas.

Photos shared on X by SpaceX Engineer (@DeannaRiceSPCX) show the new Roadster parked outdoors beside the famed Falcon 9 that stands outside company headquarters at the corner of Crenshaw Boulevard and Jack Northrop Avenue. Rocket B1019 was the first orbital-class booster ever to land after a launch on December 21, 2015 after it sent 11 Orbcomm satellites to orbit and then flew back to Landing Zone 1 at Cape Canaveral, which would be the first landing in what became SpaceX’s reusable rocket program. SpaceX chose not to fly it again. After a test fire in Florida, the booster was shipped to Hawthorne and raised upright as a permanent monument in August 2016, as Teslarati reported at the time. Putting the Roadster, which flies on SpaceX cold gas thrusters, next to the rocket that started SpaceX’s landings is symbolic in itself.

The Thrust and Rocket versions of the Roadster use cold gas thrusters fed by composite overwrapped pressure vessels, the same type of tank SpaceX flies on Falcon 9, and Elon Musk described the car as the work of Tesla and SpaceX engineers working together. Tesla lists 0 to 60 mph in under 0.9 seconds for Thrust and under 0.59 seconds for Rocket, while the base Performance model relies on a fan and ground sealing system for grip, as Teslarati detailed in its breakdown of the three Roadster configurations.

Tesla has kept the car in the spotlight since the October 15 event near Waco. Last week, the company posted a video of the Roadster’s fighter jet inspired cockpit, including a Track Mode screen with a “Thruster · 5,500 PSI” readout, which we covered in our look at the Roadster’s center display. Musk also said owners will be able to ask the car to perform the stunts autonomously, and promised a looping track at Tesla’s Texas headquarters.

The visit comes as special committees at Tesla and SpaceX weigh a possible merger, a step Musk confirmed on SpaceX’s third quarter earnings call. The Roadster, built on SpaceX hardware, has become one of the clearest examples of the two companies already building products together.

Musk said at the unveiling that Roadster production will begin in 2028. Reservations are open with a $50,000 payment, Thrust is listed as a limited release and Rocket is invite only. Tesla says the car is not approved for public road use.

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Verizon, AT&T and T-Mobile are trying to shut Starlink out before FCC vote

AT&T, Verizon and T-Mobile want 290 MHz cut from an FCC satellite plan before Thursday.

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Starlink D2D direct to device vs Verizon, AT&T (Concept render by Grok)

AT&T, Verizon and T-Mobile are asking the Federal Communications Commission to pull nearly 300 MHz of spectrum out of a proposal that would let satellite companies like SpaceX offer cell service directly to ordinary phones. The request lands one day before the agency votes on it.

The FCC will vote Thursday, October 29, on a notice of proposed rulemaking that would make an additional 482 MHz available for direct to device service, expanding the number of eligible bands from five to 13, according to the FCC fact sheet. It would also scrap the rule requiring a satellite operator to lease spectrum from carriers, replacing it with a certification that the operator has coexistence agreements in place or holds the terrestrial license itself.

That second path matters for SpaceX. As Teslarati reported earlier this month, SpaceX agreed to buy Grain Management’s nationwide 800 MHz portfolio to turn Starlink Mobile into a full US carrier, adding to the spectrum it already bought from EchoStar.

The carriers want two bands removed, 2.5 GHz and 3.45 GHz, which make up 290 MHz of the 482 MHz on the table. Through industry group CTIA, they argued that about 300 million users depend on those bands and that satellite operations in them are not technically feasible. T-Mobile, which calls 2.5 GHz the foundation of its Ultra Capacity 5G network, said in its own filing that satellite interference could wipe out up to 96% of a cell site’s uplink coverage area and cut uplink speeds by 88% to 99%.

Executives from all three carriers met with FCC staff on October 20, and T-Mobile CEO Srini Gopalan met separately with FCC Chairman Brendan Carr. T-Mobile’s role stands out because it is still SpaceX’s US launch partner for Starlink Mobile. The three carriers have also teamed up on their own satellite joint venture to pool spectrum, a move widely seen as a response to Starlink.

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SpaceX is asking for the opposite. In an October 23 filing after meetings with FCC staff and commissioners’ offices, the company asked regulators to add the 902 to 928 MHz band to the proposal. “Doing so now saves time later,” SpaceX wrote. The company also asked the FCC to modernize interference rules and align satellite deployment requirements with those for terrestrial cell networks, saying the goal is to let satellite and ground networks work together so Americans stay connected wherever they are.

The carriers have not been shy about how they view SpaceX as a competitor. On Verizon’s third quarter earnings call Monday, its chief executive said Starlink Mobile “just can’t compete with a terrestrial network” and estimated SpaceX would need four to six years and $300 billion to $500 billion to build a full US carrier network.

Thursday’s vote will not settle which bands survive. Adopting the notice opens a public comment period, with final rules to come later in the proceeding. The FCC already considered and rejected 2.5 GHz for satellite coverage once, in 2024. SpaceX also is not the only satellite player watching: the FCC approved Amazon’s $11.6 billion acquisition of Globalstar on October 27, giving its planned direct to device fleet its own mobile satellite spectrum.

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Tesla Semi catches fire in California: what we know

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Credit: KTVU

A Tesla Semi caught fire in Hayward, California, which caused both directions of traffic to shut down for hours before being completely reopened early on Wednesday, the California Highway Patrol said.

The fire occurred just after 5:30 local time in Hayward on Tuesday, as the Semi caught fire in the southbound lanes of I-880 before CHP officials made the decision to shut down both lanes of traffic due to potential risks from hazardous chemical smoke.

There were no injuries reported.

The cause of the fire is currently unknown, as neither Tesla nor the CHP have not determined a cause.

However, some images taken before the Semi was completely destroyed by the fire seem to indicate this might have been an older unit, as it appears to be one of the designs that Tesla shipped as part of its pilot program, before revising it and starting mass production just a month ago.

At the time of publication, CHP had not returned our request for a comment for additional details, including the Semi involved and any potential collaboration on an investigation between the CHP and Tesla. We will update this story when we hear back from them.

The southbound lanes were reopened at 3:30 a.m. on Wednesday, with the northbound lanes opening last night a few hours after the fire began. The CHP did state that the lithium batteries were “incredibly difficult to extinguish,” according to NBC Bay Area.

The truck’s driver said that the Semi caught fire, but he did not have an explanation.

An estimated 5,000 to 7,000 semi-truck and large commercial vehicle fires occur on U.S. roadways every year.

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