United Airlines
US Airways and American Airlines planes sit at the gates at Dallas/Fort Worth International Airport. LM Otero/AP hide caption
United Airlines planes sit on the tarmac at San Francisco International Airport on July 8, grounded by a computer glitch. Some 3,500 United passengers around the world were delayed. Justin Sullivan/Getty Images hide caption
United Airlines jets are parked at Newark Liberty International Airport in Newark, N.J. Julio Cortez/AP hide caption
A United Airlines 747-400 taxis at San Francisco International Airport in 2011. A group of flight attendants have filed suit against the airline to contest their firing over their handling of a perceived safety threat. Eric Risberg/AP hide caption
A United Airlines Boeing 787 Dreamliner at O'Hare International Airport. Scott Olson/Getty Images hide caption
United Airlines jets in San Francisco earlier this year. Justin Sullivan/Getty Images hide caption