SkyWest knows if UA fails they go with them. They're sitting on all that cash at the moment so the best thing to do is to keep UA propped up until things improve. In the meantime the investment will give SKW and edge on securing contracts (a la AWAC) and get them a say on any bankruptcy hearings.

Worst case scenario UA goes tango-uniform in which case it really doesn't matter how much SKW has stashed away in the bank.