Four months after the spectacular Falcon 9 launch pad explosion, SpaceX is preparing to launch rockets again. In a fascinating technical investigation, it was concluded that the likely blast culprit was interaction between supercooled helium and oxygen. Liquid helium at -269C is so cold that it condensed air to pooled liquid oxygen in crevices around a composite carbon fibre tank, eventually causing the explosion. SpaceX modified the configuration of the tanks and changed refuelling procedures to address the issues. Now the company is just waiting for good weather to launch ten Iridium communications satellites.
Image: Footage from a 2015 Falcon 9 launch. By Michael Seeley / CC-BY 2.0
This story is taken from the 13 January 2017 edition of The Warren Centre’s Prototype newsletter. Sign up for the Prototype here.