Frontier was profitable for a while and reasonably well established. I think that they're more likely to survive this (similar to NW/DL/UA's recent bankruptcy filings) than not. Then again, this is the type of thing that can cause a run on an airline. You get a large CC processor saying that they think that carrier is unstable and
next thing you know, the carrier is unstable. At least Frontier has a chance here, while ATA and SkyBus had none.