In a tweet on Monday, the billionaire replied to a SpaceX-themed Twitter account that asked how the investigation into SN11’s “rapid unscheduled disassembly” — or RUD — was going.
“Ascent phase, transition to horizontal & control during free fall were good. A (relatively) small CH4 leak led to fire on engine 2 & fried part of avionics, causing hard start attempting landing burn in CH4 turbopump,” he explained.
A “hard start” is when there’s ignition with too much fuel in the engine’s combustion chamber and pressure is too high, according to Space.com.
“This is getting fixed 6 ways to Sunday,” Musk said.
After ascending to a maximum altitude of 6.2 miles, as planned, the 165-foot-tall stainless steel spacecraft broke apart right before touchdown.
Dense fog obscured live video of the explosion and onboard cameras froze after the SN11 made its signature flip maneuver in preparation for landing.
CNET reported on Monday that other cameras directed at the landing pad had captured an orange glow and a storm of debris as it rained down on the exclusion zone around the pad.
“At least the crater is in the right place!” Musk tweeted on March 30.
SpaceX later confirmed that SN11 had “experienced” a RUD, marking the fourth Starship vehicle in a row SpaceX has lost since December.
The CH4, or methane, powers the SN11’s three Raptor engines, giving it more than 1 million pounds of thrust.
The Raptors were supposed to shut down once reaching the desired altitude and reignite in the last stage of the rocket’s descent for a vertical landing.
Both SpaceX’s Starship and Super Heavy — the booster stage — will be powered by Raptor engines and the company has already built the next updated Starship prototype, SN15.