Spirit Airlines is set to reduce its flights by 25% as it struggles with a second bankruptcy filing. In a memo to staff on Wednesday, CEO Dave Davis said the airline would be "redesigning and strengthening" its flight network starting in November."As planning begins, you will see a reduction of about 25% in capacity, year over year, as we optimize our network to focus on our strongest markets," David said in the memo, seen by Business Insider. A representative of Spirit did not respond to a follow-up quer ...