For the first time, SpaceX piled a section of Super Heavy tank across its height, effectively completing the assembly of the largest reinforcement rocket ever built.
While there is still a fair amount of work to weld the two halves and connect their pre-installed piping and avionics, these tasks are quite marginal and will fit the huge steel tower that is now firmly in one piece. Composed of 36 of the steel rings also used to assemble Starships, the first Super Heavy prototype – serial number BN1 – will be about 67 meters (220 feet) high from the top of its upper ring to the tail of its future Raptor engines installed.
At that time, the Super Heavy BN1 is only 3 meters (~ 10 feet) shorter than a two-stage Falcon 9 or Falcon Heavy rocket – the second and third highest operating rockets today. Of course, the Super Heavy is just a booster and SpaceX says the rocket will be at least 120 m (~ 395 feet) tall with an upper stage of starship and spacecraft installed at the top, making it easily the most launch vehicle. tall (and probably heavier) ever assembled.
Notably, the Super Heavy BN1 is not totally representative of the propellers that will support the first orbital launch attempts of the spacecraft. For unknown reasons, SpaceX seems to have abandoned the installation of any kind of landing legs on the first pathfinder and prototype. CEO Elon Musk expressed a desire to avoid the need for legs by fully capturing Super Heavy Boosters (and possibly even Starships) with a tower equipped with giant arms, but it is virtually impossible to imagine that such a totally unproven recovery mechanism is ready for large-scale testing – not to mention operational use – later this year.
First reported by NASASpaceflight and later confirmed by Musk himself, SpaceX hopes to be ready to begin launching orbital starships in July 2021, just four months from now. By NASASpaceflight, this first launch attempt will nominally use the Super Heavy booster BN3 and Starship SN20. The Super Heavy BN1 is expected to remain grounded, serving as a test base for inaugural pressure and proof tests, as well as one or more possible Raptor static fires (Update: confirmed by Musk)
If this process goes according to plan, Super Heavy BN2 will continue where BN1 left off and will attempt at least one short jump test, among other qualifying tasks. In the interim between this feat and the launch preparations for the Super Heavy BN3, it’s safe to assume that BN2 or BN3 will support some kind of iterative static fire test campaign similar to what SpaceX once did with Falcon 9, gradually increasing from tests with one half – more or less a dozen engines for static fires with 20 or more – possibly up to and including a total complement of 28 Raptors.
The first of its kind, the BN1 ‘thrust donut’ booster – a donut-shaped plate for the Rocket Raptor’s central engine assembly attached – appears to have been fitted with hardware for four engines, suggesting a roof for static fire testing. It is unclear when the Super Heavy will roll over to the launch pad for testing, but it is safe to say that SpaceX will probably not wait long after Starship SN11 ends its high altitude launch campaign. Stay tuned for updates!