I'm not aware of any modern US rockets (other than SpaceX) that install COPV tanks inside LO2 fuel tanks. SpaceX is certainly getting a performance gain from th

I'm not aware of any modern US rockets (other than SpaceX) that install COPV tanks inside LO2 fuel tanks. SpaceX is certainly getting a performance gain from the design at the risk of these kind of thermal related failure modes. I hope they figure out how mitigate these failure modes as a COPV exploding inside a LO2 tank is scary! Especially once they start flying humans on-board in 2018 or 2019.