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SpaceX to put custom Starship propellant storage tanks through first trial

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In the latest twist in the saga of SpaceX’s custom-built Starship launch pad propellant storage tanks, the company appears to have retroactively decided to build small prototype meant solely for testing.

Known as a ‘test tank,’ the relatively small steel structure was fairly rapidly assembled from parts of an older Ground Support Equipment (GSE) tank scrapped in July over the last week or so. SpaceX completed the first Starship-derived propellant storage tank in April 2021 and rapidly rolled that tank (GSE1) and a second (GSE2) from the build site to the orbital launch pad just a few weeks apart. Less than a month after that, SpaceX also completed GSE tank #3, though things seemingly devolved into chaos immediately thereafter.

Only three months later would GSE3 finally be transported to – and installed on a concrete mount at – Starship’s first orbital launch site, and only after a number of structural modifications and in the footsteps of GSE tanks #5 and #6. Little is known about why SpaceX’s custom GSE tank production faltered so soon after it began, why none of the five Starship-sized tanks installed at the orbital pad have been fully plumbed or subjected to any kind of testing, or why structural modifications were seemingly required after the fact. However, it’s safe to say that SpaceX’s brand new GSE ‘test tank’ is now at the center of the mystery.

Starship S20, test tank GSE4, and (half of) Super Heavy Booster 3. (NASASpaceflight – bocachicagal)

Thankfully, at minimum, the rapid appearance of SpaceX’s first GSE test tank returns some level of familiarity to the brief but chaotic history of Starship’s orbital launch pad propellant tanks. Test tanks are nothing new and have been an integral part of Starship development since Test Tank 1 first headed to SpaceX’s suborbital launch (and test) facilities in January 2020. In the 20 months since, SpaceX has built and tested seven small test tanks, several of which didn’t survive.

Whether intentionally destroyed or not, each test tank explicitly helped SpaceX qualify new manufacturing techniques, different materials, and different skin thickness and generally gather data more quickly and cheaply than full-scale prototypes would allow. Most recently, for example, SpaceX seemingly successfully tested a Super Heavy booster test tank, subjecting the prototype to cryogenic liquid nitrogen and using hydraulic rams to simulate the thrust of nine Raptor engines on an unproven disk-like thrust structure.

Now, almost as if SpaceX snapped out of a trance and remembered the utility of test tanks, the company has assembled a subscale GSE prototype presumably meant to verify that its custom-built propellant storage tanks can handle a set of conditions significantly different from the Starships they’re derived from. In this case, that GSE tank was quite literally built from scrapped sections of GSE tank #4. In fact, the top half (forward dome section) was quite literally cut off of GSE4 after the tank was scrapped last month for unknown reasons.

Over the last several months, while GSE tank production and installation took an unexpected hiatus, SpaceX workers slowly but surely welded steel rings (stiffeners) to the exterior of GSE1, GSE2, and GSE3. When GSE5 and GSE6 eventually headed to the pad, they left with those stiffeners already installed, implying that whatever tripped SpaceX up was likely structural. The GSE4 test tank also includes external stiffeners along each circumferential weld (where rings were stacked or domes joined).

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Test tank GSE4. (NASASpaceflight – bocachicagal)
SpaceX’s GSE tanks and their “cryo shells.” (NASASpaceflight – bocachicagal)

At the same time as SpaceX was (or wasn’t, for several months) building its own GSE tanks, contractors normally tasked with assembling water towers and storage tanks in situ built eight massive 12m (~40 ft) wide tanks of their own. Deemed “cryo shells,” much like their name suggests, those tanks are meant to fully enclose SpaceX’s GSE tanks. SpaceX will use those shells to insulate their thin, single-walled steel propellant tanks, thus keeping their cryogenic contents cryogenic for as long as possible. How they’ll be insulated is unclear, though.

Based on the seemingly retroactive decision to strengthen the exterior of those GSE tanks, the general consensus as of late is that SpaceX wants to pull at least a partial vacuum in the gap between shell and tank. It’s also possible that SpaceX will do the opposite and pressurize that gap (as much as possible) with an insulative gas like nitrogen. Extra confusion comes from the fact that Starship tanks are technically designed to support a literal spacecraft (operating in a near-total vacuum) without the need for external stiffeners.

Additionally, it’s fairly clear that SpaceX hasn’t built a custom subscale cryoshell or concrete installation pad for its GSE4 test tank, meaning that it will really only be useful for testing some of the loads operational GSE tanks will experience inside their sleeves. Additionally, given that SpaceX has already completed six of the orbital pad’s seven GSE tanks and all seven of their cryosleeves, the discovery of any significant issues during GSE4 testing could easily trigger months of rework and delays. With any luck, though, GSE4 will sail through an imminent test campaign, clearing the way for SpaceX to finish plumbing, sleeving, and activating Starship’s first orbital launch site tank farm.

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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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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Tesla’s ‘Emergency Drive Away’ function gets its first use in the real world

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Credit: Tesla

Tesla’s launch of the “Emergency Drive Away” function a few months back offered owners a safe option to evacuate an area if they were in reasonable danger. The function finally got its first use in the real world, but it appears it was by mistake.

A video shared by u/Joshalander in the r/TeslaLounge subreddit recorded the instance from his vehicle and said the incident took place in Austin this past weekend during the city’s F1 Race.

“Was charging around 6 AM this past Sunday in Austin before heading to the F1 race and heard a pop. Looked over and saw the new emergency drive-away feature in action. Genuinely felt bad for the dude when he got out and realized what happened, since he looked exhausted and only seemed to half-read the prompts.”

Emergency Drive Away unlatches the Supercharger connector from the vehicle, but still causes damage to both the car and the Supercharger. Tesla has said that it will cost up to $25,000 in repairs to have everything fixed back to normal.

Additionally, the company said that if it were not used in an emergency situation, the driver of the vehicle who activated the Emergency Drive Away feature would be responsible for all repair costs.

Tesla constitutes the following situations as reasonable justifications for activating the feature:

  • You face an immediate threat to your life or personal safety.
  • You must leave the area immediately.
  • Exiting the vehicle is unsafe.
  • Unplugging the charge connector would unreasonably delay your departure or expose you to a risk to your personal safety.

After using the feature, Tesla requires the driver to schedule Service so the car can be inspected.

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