If frontier can increase ancillary revenue and continue to cut costs, it is likely they will survive on their own as stand alone airline. The SEC fillings are very misleading and make F9 look like a total money pit, however most of F9s losses are a direct result of the deadweight from YX and RAHs spare/excess aircraft.

It appears the usage of regional aircraft(not including 190s) has been counter productive to F9s LCC business model which has been going on for roughly ten years now.

It appears F9 will be finally getting rid of all 135/145s and Qs by the end of the year along with A318s and other unprofitable routes resulting in a dramatic reduction of their CASM(excluding fuel). F9 already has lower costs than WN.