
A prototype of the SpaceX Starship launch vehicle has passed a cryogenic pressurization test.
The prototype, designated Starship SN4, completed the key test at the SpaceX Boca Chica facility on April 27. According to SpaceX founder and CEO Elon Musk, testing pushed the pressure within the prototype’s main tank to 4.9 bar. Musk admitted that the target was “a softball” but reiterated that it was good enough to move ahead with the vehicle’s first flight.
Through several responses to Musk’s original tweet announcing the success of the test, the mercurial CEO explained that SpaceX hopes to fit SN4 with a Raptor engine and conduct a static first test later this week. Once that is completed, SpaceX plans to attempt a 150-meter “hop test”. This will see SN4 liftoff and climb to an altitude of 150 meters. It will then return to Earth completing a propulsive soft landing.
It is currently unclear if SN4 will be used for any additional testing following the 150-meter hop. Musk has stated that the prototype will only be fitted with one of the company’s next-generation Raptor engines. The next iteration, SN5 will be an upgraded variant and will be fitted with three Raptor engines.
The development of the Starship launch vehicle has been one of trial and error. Three previous versions of the Starship prototype have been destroyed in spectacular fashion, all during the same cryogenic pressurization testing just completed by SN4.