SpaceX announced recently about Starship SN4’s next phase, a cryogenic proof test. The operations begin this Sunday (April 26) at the space company launch platform in Boca Chica. SN4 needs to be tested to prove its flight worthiness.
Until now, only the SN2 Starship passed the cryogenic proof test. But, that time was different because SN2 wasn’t a full-scale vehicle. SN4 has all the chances to pass the test, as SN3 operations proved to be a failure, but useful in terms of mechanics.
SpaceX Starship Prepares For Another Test
SpaceX is ready for SN4’s proof test that will develop in two parts. First, the spacecraft will be pressurized with gaseous nitrogen.
Engineers will then return to the platform to examine SN4 before reaching the last phase – the cryogenic proof test. If the spacecraft becomes the first full-scale prototype to succeed, then it will undergo engine testing within the following weeks.
Currently, SpaceX developed three flight-ready Raptor engines. The engines are not installed only after a prototype passes the cryogenic proof test, as that test utilizes hydraulic pistons to simulate the energy made by Raptors during the flight.
More About the SpaceX Starship Cryogenic Test
If SpaceX can put a Raptor engine on SN4, engineers will need to develop checkouts of the three engines on the spacecraft. The checkouts include, too, a gimbal, fuel pre-burner tests, and an ignitor. SpaceX will become then ready to try a static fire.
It is still unknown if the space company will begin with a single-engine static fire or choose to perform a static fire with all engines. It will also be the first time when SpaceX fully powers a Starship with liquid oxygen and cryogenic methane.
Other information regarding the SN4 prototype includes a limitation to only small hops that don’t need a relight of the Raptor engines, according to SpaceX’s CEO, Elon Musk. Also, either the SN5 or SN6 spacecraft will get flaps installed.