Spirit Airlines axes flights in 12 cities as it fights for survival while United, other airlines circle
1. Spirit Airlines terminates flights in multiple U.S. cities amidst bankruptcy. 2. United Airlines increases flights to areas served by struggling Spirit. 3. Analysts expect larger airlines to gain from Spirit's difficulties. 4. Spirit filed for Chapter 11 bankruptcy for the second time this year. 5. The airline faces operational scaling and significant cash concerns.