News
SpaceX to put custom Starship propellant storage tanks through first trial
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.
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).
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.
Investor's Corner
Tesla Optimus Gen 3 shows off a cleaner, factory-ready design in new app discovery
Renders hidden inside Tesla’s Android app show Optimus Gen 3’s design before any official reveal.
![Tesla Optimus Gen 3 [Credit: Tesla]](https://www.teslarati.com/wp-content/uploads/2026/03/tesla-optimus-gen3-diner.jpg)
Tesla may have accidentally given a first look at its newest Optimus Gen 3 humanoid robot when photos were found in the Tesla smartphone app.
Design files tucked inside a recent Android version of the Tesla app appear to show the third generation humanoid robot next to the older Gen 2.5 prototype. The assets were extracted from the app package by Tesla community member @wholemars, who posted the renders on X late Tuesday night before deleting them. The Tesla Newswire reshared the side by side comparison on Wednesday, and the images have circulated widely since.
Tesla Optimus Gen 2.5 vs Gen 3 comparison via @WholeMars on X
The files are labeled “gen3” and were built as models for Tesla app’s own interface, as validated directly by Grok to be official.
The comparison shows a robot that looks built for a factory line rather than a lab bench. Gen 2.5’s exposed mechanical linkages and gold plating on the knees and shins are gone. In their place, Gen 3 uses matte black fairings on the lower legs, paired with a more contoured champagne gold body. Flexible covers now seal the joint where the torso meets the upper thighs, keeping bearings and moving parts sealed from debris and unnecessary contact.
The body panels fit more tightly, and the hands, which Tesla has said carry 22 degrees of freedom, look far more refined than those on earlier units.
This most recent leak fills a gap Tesla has left open for most of the year. Elon Musk said on March 31 that Optimus 3 was walking around but needed “some finishing touches” before it could be shown, a delay Teslarati covered when Tesla missed its first quarter reveal target. Musk later said Tesla would hold the design back until closer to production, partly to keep competitors from copying it. No reveal date has been announced.
The app itself has been preparing for Optimus for months. In July, code in the Tesla app pointed to a dedicated robot phone key, a consent screen for collecting video and spatial data while Optimus works inside a home, and an alert system for low battery and mechanical faults. Finished 3D models of Gen 3 suggest the interface owners will eventually use is moving past placeholder code toward something Tesla intends to ship.
Manufacturing is moving in parallel. Tesla tore out the original Model S and Model X lines at Fremont this summer to make room for Optimus production, with a planned capacity of one million robots a year. At Giga Texas, the steel frame of a dedicated Optimus factory is nearing completion ahead of a targeted 2027 start, with Musk pointing to an eventual output of 10 million units annually.
News
Tesla Semi lands the biggest electric truck deal in U.S. history
Tesla leads a record 2,500 truck order, but not every truck will be a Semi.
Tesla has landed the largest electric truck order in U.S. history. ZET SCALE, a new alliance of shippers and carriers, named Tesla its primary manufacturer on Tuesday for an initial order of 2,500 electric Class 8 trucks. The deal alone would nearly double the number of electric heavy trucks operating in the country.
According to the press release from Catalyst Mobility, the nonprofit formerly known as CALSTART, Kenworth, RIDE and Volvo were also selected as secondary manufacturers that carriers can pick if their operations call for it. No split between the four brands has been published, so the exact number of Semis in the order is not yet known.
Tesla was selected as the primary OEM for the largest electric Class 8 order in the US by ZET SCALE, a new shippers’ alliance
With 2,500 Semis on order, this will double the entire US electric Class 8 fleet
We’re serious about scale, and ZET SCALE is too!… pic.twitter.com/IiTAdzgken
— Tesla Semi (@tesla_semi) September 22, 2026
Tesla won the top slot through a competitive request for proposals. The alliance, which Catalyst Mobility runs with the Smart Freight Centre, scored bidders on price, range, charging capability and production capacity. Pooling freight demand from founding shippers, including Microsoft and PepsiCo, let every truck maker bid lower than it would for a single fleet. “The Tesla Semi is designed for lower cost per mile operations than diesel,” said Dan Priestley, director of the Tesla Semi program, as noted in the press release.
The financing is built to pull in carriers who have avoided electric trucks. ZET Financial is issuing the purchase order for all 2,500 units and will place them with fleets through a fair market value lease. The trucks will be deployed over the next few years across 10 freight hubs in Los Angeles, Stockton, Bakersfield, Seattle and Tacoma, Houston, Dallas, San Antonio, Chicago, Atlanta, and the Newark and New York area. ZET SCALE says the first order is only the opening round, with a longer term goal of 10,000 trucks or more.
Even if Tesla ends up with only a majority share, it would still be the biggest Semi deal to date. Einride’s 500 unit order in August was the previous record, and WattEV’s 370 truck order in May was the largest California deal at the time. Einride’s CEO has since said he expects all 500 trucks delivered by the end of 2027.
The announcement lands two days before Tesla formally inaugurates its Semi factory in Nevada on September 24. The 1.7 million square foot plant sits next to Gigafactory Nevada’s 4680 cell lines and is designed for 50,000 trucks a year.
Tesla has expanded Grok from an in-car chatbot into a hands-free work assistant. On September 22, Tesla officially launched Grok Bot capability, confirming that drivers can now manage email, calendars, files, chats, and tasks by voice and then hand more ambitious errands to the AI-fueled productivity cheat code.
Grok itself is built by xAI. The new car features split into two layers: Connectors link Grok to outside accounts. Grok Bot, currently limited to SuperGrok Heavy subscribers, can complete multi-step tasks such as placing a usual coffee order, booking a reservation, or scheduling an appointment. It truly puts the driver in a nearly complete hands-free driving and productivity setting, with ironically the only task truly requiring your hands being to touch the “Start Self-Driving” button.
We were granted access to Grok Bot’s Tesla integration a few weeks back, and we’ve been able to do a handful of things with it. On a handful of occasions, we’ve used it to order food and have it ready for pickup slightly later into the evening; we’ve managed to pick up groceries after a day of errands with Grok Bot, and outside of the car, it’s helped with budgeting and even my fantasy football draft.
We’ve been using @Grok Bot in Tesla for a few weeks after gaining Early Access, which we thank the awesome engineers for
Grok Bot makes things much easier across your entire life. From the Tesla, I’ve used it to place pickup orders for my Fiancée and I, we’ve ordered groceries… https://t.co/ZJSLieG1s5
— TESLARATI (@Teslarati) September 22, 2026
Tesla shows another way to utilize it: in their demo, a driver says “Hey Grok,” asks the assistant to check an inbox, and hears that a message concerns a weekend reservation. Grok then scans the calendar, reports no conflicts, and confirms the Tahoe trip is clear. It can also add check-in details to a road-trip itinerary. The point is not novelty chat. It is keeping eyes on the road, or on Full Self-Driving, while the car handles the paperwork of a trip:
.@Grok in your Tesla can now do meaningful work for you
With Connectors, you can manage your inbox, clean up your calendar, or talk through existing files/chat/tasks – all hands-free pic.twitter.com/W1LuybQh0P
— Tesla (@Tesla) September 22, 2026
This Grok rollout is not a gadget add-on as much as it is Tesla’s thesis in software form: the car should stop being a machine you operate and start being a room you occupy.
Connectors and Grok Bot treat the cabin as an office that happens to move, and that has truly been Tesla’s intention for years now. The car has slowly become an extension of a home more than a vehicle. Inbox, calendar, groceries, takeout, and reservations become voice work, not dashboard chores that you need to do before you get in your car.
Responsibility shifts from the driver to the stack, and as many Tesla owners rely on FSD for travel, Grok Bot now handles the monotony of dinner reservations or appointments.
![Tesla Optimus Gen 3 [Credit: Tesla]](https://www.teslarati.com/wp-content/uploads/2026/03/tesla-optimus-gen3-diner-80x80.jpg)
Tesla Optimus Gen 3 shows off a cleaner, factory-ready design in new app discovery
Tesla Semi lands the biggest electric truck deal in U.S. history
