SpaceX fires up 11 engines as it prepares a massive rocket for an orbital test

On Tuesday, SpaceX launched its Super Heavy rocket for about 12 seconds, making it the longest launch of the massive booster to date. The test, which ignited 11 of the 33 Raptor rocket engines, came as SpaceX continues to work toward an orbital launch attempt of this Super Heavy first stage and its Starship upper stage.

Earlier this month, SpaceX fired 14 Raptor engines on that booster in a matter of seconds, so Tuesday’s test didn’t set a new record for the number of engines tested. However, this “long-lasting” firing is the longest period of time that so many Raptor engines have been fired at once.

So what happens now? The path to orbit for SpaceX and its Starship launch system is unclear. He was previously the founder of SpaceX said Elon Musk the next step was to fire a subset of the Super Heavy’s engines for about 20 seconds to test autogenous pressurization. This method of pressurizing propellant tanks uses gases generated on board the rocket rather than a separately charged inert gas such as helium.

Tuesday’s test may have been a slightly shorter version of this autogenous pressurization test — 12 seconds instead of 20 — or it may have been something else. The company is taking an iterative approach to the design and development of the Starship vehicle and its Super Heavy first stage, so its test plans are liquid, as opposed to the rocket’s cryogenic propellants.

In all likelihood, SpaceX still needs to complete several key tests before the combined super-heavy rocket and Starship upper section are launched from the company’s Starbase facility in South Texas. SpaceX is expected to conduct at least a short test launch of all 33 Raptor engines simultaneously to gain confidence in the integrity of the rocket’s complex propulsion system fuel and pressurization plumbing systems. The top of the Starship will then be stacked on top of the Super Heavy and the combined vehicles must complete a wet dress rehearsal.

What seems clear is that SpaceX is maturing its approach to working with the Starship architecture, as recent tests, including Tuesday’s, have ended without apparent failures.

After completing all of its technical preparations, SpaceX must also obtain a launch license from the Federal Aviation Administration, which is in the process but not yet completed. While it remains theoretically possible that Starship will make its attempt to launch into orbit in December, there is an increasing likelihood that the test flight will slip into early 2023.