Twice now I've had a jetpack unexpectedly break when being attacked. The first time I assumed I had missed a durability indicator or maybe the energy was completely drained when getting hit, but the second time around there definitely was no indicator and I had well over half the energy left. If they're supposed to be able to break, then this is a suggestion that there should be an indicator for the remaining durability, and if they're not, then this is a bug.