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Elon Musk Reveals What Caused a SpaceX Prototype to Mysteriously Explode

The SN11 launched from the company's South Texas facilities last week but exploded upon landing.


SpaceX CEO Elon Musk took to Twitter yesterday to explain why the company's Starship prototype SN11 inexplicably exploded last week during a test flight. 

Last Tuesday, SpaceX launched the SN11 from its South Texas facilities, according to The rocket soared to a maximum altitude of the planned 6.2 miles but exploded as it tried to land. 

Related: Pentagon, SpaceX Sign Contracts Worth a Combined $159 Million to Launch Spacecraft for U.S. Military

When a Twitter user asked Musk if the CEO had any updates as to what the cause could have been, Musk attributed the detonation to a plumbing issue. 

"Ascent phase, transition to horizontal & control during free fall were good," he wrote on Twitter. "A (relatively) small CH4 leak led to fire on engine 2 & fried part of avionics, causing hard start attempting landing burn in CH4 turbopump. This is getting fixed 6 ways to Sunday." 

In other words, a small methane leak from the rocket's Raptor engine caused an ignition that led to the SN11's demise. As CNET notes, the explosion caused a "hell storm of debris" that was captured by remotely operated livestream cameras. 

SpaceX plans on conducting its first orbital flight in June. The company's ultimate goal is to bring people to the moon, Mars and other destinations. 

Justin Chan

Written By

Entrepreneur Staff

Justin Chan is a news writer at Previously, he was a trending news editor at Verizon Media, where he covered entrepreneurship, lifestyle, pop culture, and tech. He was also an assistant web editor at Architectural Record, where he wrote on architecture, travel, and design. Chan has additionally written for Forbes, Reader's Digest, Time Out New YorkHuffPost, Complex, and Mic. He is a 2013 graduate of Columbia Journalism School, where he studied magazine journalism. Follow him on Twitter at @jchan1109.