Flight 5735 operated by China Eastern Airlines with a Boeing 737-800 NG aircraft was at an altitude of 29,100 feet when something went wrong. It was in the skies over the hills of southern China. Then at 2:20 p.m. on March 21, the aircraft crashed to the ground. The aircraft was seven years old. Among the three pilots sitting in the cabin was a seasoned aviator with decades of experience behind him....