Elon Musk Says SpaceX Rocket Launches Might Resume Next Month - The New York Times

A multifaceted rocket science case study

"Last week, SpaceX released a statement that it was focusing the investigation on one of three helium containers within the oxygen tank. During launch, as the liquid oxygen is consumed, the helium is heated up and released to maintain pressure within the tank. The company said that its tests had replicated the rupture of the helium containers, made of carbon fiber composite materials.

“It basically involves a combination of liquid helium, advanced carbon fiber composites and solid oxygen,” Mr. Musk said. “Oxygen so cold that it actually enters solid phase.”"

Elon Musk Says SpaceX Rocket Launches Might Resume Next Month - The New York Times