In a small but important step towards activating a cushion capable of launching the largest and most powerful rocket ever built, SpaceX has “coated” one of its Starship-derived propellant storage tanks for the first time. times.
Starship is a fully reusable two-stage liquid rocket designed to ultimately reduce the cost of orbital launch by at least one magnitude, opening the door for humanity durable expansion to Earth’s orbit, the Moon, Mars and even beyond. To accomplish this great feat, he must be a massive rocket. Measuring approximately 120 m (~ 395 ft) high and 9 m (~ 30 ft) wide, Starship and Super Heavy will weigh in the order of 300 tonnes (~ 675,000 lb) when empty.
When filled to the brim with cryogenic liquid methane (CH4) and liquid oxygen (LOx) propellant and gas, however, a two-stage spacecraft will easily weigh over 5,000 tons (11 million pounds) shortly before and after. take off. Additionally, SpaceX wants to be able to launch at least two Starships from Boca Chica in quick succession. To meet the enormous needs of back-to-back Starship launches, SpaceX therefore had to design and build what will be the world’s largest fleet of launch pad tanks.
Work on this reservoir farm is already well advanced, although progress has been slower than expected. The site’s foundations and a few associated blockhouses were mostly completed by January 2021. By early April, the company had completed the first of at least seven steel propellant storage tanks at its Starship plant and had it rolled to to the launch pad for installation.
Notably, SpaceX chose to manufacture these storage tanks itself and ended up building structures virtually identical to the tanks that already make up most of the Starship and Super Heavy airframes in flight. Depending on whether they’re intended to store liquid oxygen or methane, the seven tanks that SpaceX is building are 26 or 30 meters (85 or 100 feet) in height – though the concrete brackets they’re attached to on the launch site are of such size. that all storage tanks will have the same final height.
Of course, being made with the same tools and from the same steel as Starship and Super Heavy, that means SpaceX’s custom storage tanks are steel shells of just over 4mm (~ 1/6 “). thick – about as bad as it gets to keep cryogenic rocket fuel … cryogenic. If SpaceX just used these unmodified tanks, it would be next to impossible to store Starship fuel for more than a few hours – and maybe a few. minutes – without heating up beyond the point of use.
As such, the final design of SpaceX’s Starship tank farm involves seven storage tanks derived from Starship. and seven tanks built by a contractor sleeves. Measuring approximately 12 m (~ 40 ft) wide and 40 m (~ 130 ft) high, these “cryogenic shells” will house the seven tanks built by SpaceX, allowing the company to close the 1.5m gap. (~ 5 ft) between them with solid, gaseous insulation, or a combination of both. With those shells and insulation, SpaceX’s bespoke Starship tank form should be more than capable of storing cryogenic liquid oxygen and methane for days, if not weeks.
As of August 5, SpaceX has installed three of Starship’s custom Ground Supply Equipment (GSE) tanks (with a fourth moved to location Thursday), moved two “cryogenic shells” to temporary storage locations on the pad, and installed a cryogenic shell that turned out to be a million gallon water tank. SpaceX on Thursday “sheathed” one of these storage tanks for the first time, marking a significant step towards activating a tank farm capable of supporting the debut of Starship’s orbital launch. Four more rounds are more or less over, with the eighth and final round probably a week or two from the end.
A fifth GSE tank is also more or less complete, two more remain. However, with a few basic calculations, it is possible to determine that SpaceX’s orbital launch pad likely only needs five cryogenic tanks (three oxygen, two methane) – and possibly as little. only four – to support Starship’s first orbital test flight (s). With SpaceX finally starting to install tank sleeves, it’s possible that this four or five tank milestone – and early testing of SpaceX’s untested, custom storage solution – is now much closer.