SpaceX builds launch pad tanks from spaceship parts and that’s a big deal

SpaceX has begun installing the first of many propellant storage tanks at its first orbital launch facilities in South Texas – a mostly ordinary and expected step made extraordinary by the fact that these tanks will be built from parts of Starship. .

Labeled “GSE” for Ground Support Equipment, the first signs of these self-built storage tanks began to appear at SpaceX’s Boca Chica Starship plant less than two months ago in mid-February. Weeks later, the first of these SpaceX-branded cryogenic storage tanks is on its way for installation (and insulation) at the launch site, while at least two more tanks are nearing completion. .

While a few starge tanks on the ground may seem like a distraction from a program tasked with building the world’s largest (and fully reusable) rocket, the existence of these tanks is far more important than it is. appears there at the outset.

I just realized that this is a much bigger deal than it seems. For SpaceX to design and build its own custom bulk product storage tanks instead of buying what is arguably fairly common and cheap out-of-the-box technology, Starship’s production has to be DIRT CHEAP. https://t.co/u7KNDXWcuf

– Eric Ralph (@ 13ericralph31) April 6, 2021

Put simply, rocket propellant storage – even for extremely cold cryogenic liquids like the ones SpaceX uses – is a thoroughly problem solved. Many commercial suppliers exist and the industrial demand for virtually identical tanks is much higher, further reducing the costs of commercial tanks even for those with niche use cases due to economies of scale. For SpaceX purposes, significant discounts could be obtained given that the company would need to purchase around three to four dozen 100,000 gallon commercial tanks (COTS) to provide a launch pad with enough product for two back-to – the launches of Starship and Super Heavy.

This initial launch capability – which SpaceX appears to be working on – would likely allow the company to begin in-orbit refueling test flights (and Starlink launches, perhaps) immediately after their completion. However, this initial capacity would not be sufficient for ambitious missions to Mars, the Moon or higher Earth orbits; where a vessel should be quickly refueled with 3-10+ tanker launches. A launch facility capable of supporting 5-10 consecutive launches (optimally a few hours apart) would require significantly more propellant storage.

The point is, for the initial goal of two (or more) launches between restocking commodities, SpaceX could likely acquire the few dozen new storage tanks it would need for a few million dollars each at a total cost. probably between $ 50 million and $ 100 million. Instead, SpaceX decided to design and build its own propellant storage tanks. More importantly, the GSE tanks that SpaceX has already started building appear to be virtually identical to spacecraft.

In other words, SpaceX is effectively taking identical rocket parts, tweaking a handful of those parts slightly and turning what could have been a rocket into a propellant storage tank. This is important because compared to every other rocket in history, including even SpaceX’s Falcon 9 and Heavy, building storage tanks with rocket parts unchanged on a rocket assembly line would be like hiring Vincent. van Gogh to paint the track lines.

Ever since Elon Musk made the radical decision to switch from composite structures to stainless steel, Starship has always wanted to be radically unlike any big rocket before him. Basically, using base steel, the CEO envisioned SpaceX would be able to build spaceships fairly easily and for pennies on the dollar alongside SpaceX’s exceptionally affordable Falcon 9. Over the past 18 months, it has become apparent that SpaceX has built a factory capable of producing one or two massive steel rockets per month and is prepared to consign at least four or five of those Starship prototypes to anything but guaranteed failures. for the sake of data collection and iterative improvement.

Technically, the most logical conclusion would be that Musk was right and that SpaceX quickly developed the ability to build steel rockets larger than any other launch vehicle on Earth for maybe $ 5 million or less each. However, SpaceX is also raising around $ 1 billion to $ 2 billion in venture capital per year, so they could technically afford the cost of extremely expensive prototypes of spacecraft if the company was convinced that ‘there was a way to reduce those costs and achieve the goals. necessary for the rocket to make economic sense.

Now, the existence of self-built propellant storage tanks virtually identical to the cells of airworthy ships almost guarantees that SpaceX is already building ships for a few million dollars apiece – and maybe a lot less. Over a year ago, Musk said SpaceX was already building the Raptor engines that would power Starship and Super Heavy for less than $ 1 million each and was working on mass production of a simpler variant for less than 250,000. dollars. Beyond motors and primary structures, Starship hardware is fairly straightforward and ranges from Tesla-derived motors, basic flaps and landing legs to pressure vessels (COPVs) and wiring. SpaceX has achieved this extraordinary profitability despite the fact that Boca Chica is still far from the level of volume production targeted by Musk, which means that there is still much more efficiency to be achieved.

For now, with virtually no retooling and the exact same assembly line, SpaceX’s South Texas rocket plant is busy producing massive launch pad tanks – one of which is already gearing up for installation while two others accelerate towards completion. In total, SpaceX appears to be preparing the foundations for seven 9m wide (30ft) and 27.5m high (90ft) spacecraft-derived tanks that are expected to be capable of storing ~ 2,200 tons (4.9 million pounds) of sub-cooled liquid methane in three tanks. and ~ 7,300 tonnes (16.1 million pounds) of liquid oxygen in the other four tanks – enough for two Starship orbital launches.