Page:CAB Accident Report, United Airlines Flight 21.pdf/9

 time of only 2,456 hours and 59 minutes, had never undergone such an overhaul.

The propellers installed were Hamilton Standard, hydromatic, constant speed, full-feathering propellers, model No. 23E50-109. The maintenance records introduced at the hearing show that at the time of the engine overhaul on November 28, 1940, the left propeller hub, No. 34680, had a total service time of 4,980 hours and 53 minutes, and the blades approximately 1,790 hours, while the right propeller hub, No. 35767, had a total service time of 5,908 hours and 53 minutes and the blades approximately 1,200 hours. At the time of the last engine overhaul these propellers were dismantled, etched, and thoroughly overhauled.

The testimony taken at the hearing and the records introduced therein show that at the time of the engine overhaul a complete inspection of the aircraft was made and all necessary maintenance repairs and replacements of the radio equipment, de-icing equipment, instruments, cabin equipment, and accessories were completed and the airplane thoroughly flight checked.

The record shows that since overhaul, the airplane had received the inspections and checks prescribed by United and approved by the Civil Aeronautics Administration. An inspection by United's