By Austin Ramzy and Keith Bradsher
The investigation into the crash of China Eastern Flight 5735 is mystified by the extensive experience of its flight crew. The pilot, Yang Hongda, and the first co-pilot, Zhang Zhengping, possessed a combined total of more than 39,000 flying hours, and China Eastern Airlines officials stated they had no health problems or faults on their records. The Boeing 737 plunged from a cruising altitude of 29,000 feet in good weather, prompting a wide-ranging investigation. Rescuers have recovered the cockpit voice recorder and other important debris, some as far as six miles from the main crash site.
