ted rolands, cnn, yuma, arizona. >> southwest's entire fleet is made up of various models of the boeing 737. all told, the airline has 558 of them. the fleet has an average age of just over 11 years. each aircraft flies an average of six flights per day. that's just under 11 hours each day. southwest is awaiting government approval to buy air tran airways. as ted rowlands mentioned, the worst accident was this type was 23 years ago over hawaii. a flight attendant died and many people were hurt. tomorrow night, we will speak with one of the passengers on that flight. ucla professor emeritus eric beckland. another close call in the air today. an atlantic southeast airlines jet, a delta regional partner, was forced to make an emergency landing in little rock, arkansas, after striking a flock of birds. you can see the damage to the plane's nose and around the engine. the 49 passengers and crew members were shaken but nobody was hurt.