Page:CAB Accident Report, Allegheny Airlines Flight 604.pdf/6

- 6 - trim and resulting drag. He also noted that in demonstrations of simulated engine failure at V$1$ ". ..  we would wait until we had around eight or nine hundred feet (m.s.l.), and were approximately four and a half or five miles off the end of the runway before attempting to go to a clean configuration." With regard to the minimum airspeed of 126 knots for the clean configuration he stated that ". . . if you get low enough in airspeed, without any flaps, that you can get into buffet onset, where if by extending the flaps before you get into this critical area, you can perhaps regain and get back sane of the performance that you would lose if you got into buffet. His solution would be a ". . . configuration with takeoff power on, and water, all 11 degrees of flap. Climb performance in that condition is almost twice the climb performance in the single-engine (en route climb) configuration." This would develop a straight-ahead climb to 1,500 feet in approximately three minutes with a temperature of 78 degrees. He stated that the turning_radius for 140 and 150 m.p.h. should have been 0.53 to 0.7 miles respectively, using a 20-degree bank.

1.16 Crew training

The Director of Flights for Allegheny testified regarding company training and operating procedures He stated that all pilots are-trained to "fly the aircraft" at crucial times such as an engine failure on takeoff. The recommended procedure for this type of an emergency, in addition to feathering the engine and fighting any fire, includes climbing straight ahead to an altitude of at least 400 feet before retracting flaps. He pointed out that the manual also requires at lease one knot of airspeed in excess of 115 knots for every degree flaps are raised from the 11-degree takeoff setting, and that the best rate of climb is obtained with zero flaps providing the airspeed exceeds 126 knots. The pilots are taught the effect of lowering flaps from the clean configuration in order to bring the aircraft out of the pre-stall buffet zone if airspeed does decay, and they also practice turns using 30 degrees of bank during single engine operation. He estimated that under normal circumstances; flaps would he retracted_approximately 1:15—1:30 minutes after takeoff at Williamsport.

2. ANALYSIS AND CONCLUSIONS

2.1 Analysis

The aircraft had been maintained in accordance with FAA regulations, and the gross.weight and c.g. were within allowable limits. The crew was properly certificated.

The right engine power loss is attributed to a failure of the front row master rod and subsequent breakup of the associated link rods. Since the piston pin bushing was found still wrapped around the piston pin, it is believed that the failure occurred in the strap area of the master rod. The-peened and rolled over condition of the front row-master and link rods prevented determination of the enact point and cause of the failure.

The amount of power being developed by the left engine at impact was derived from pertinent evidence and data. The calculations revealed that the power was 2,215 HP for a 34 degree propeller blade angle and 2,410 HP for a 35 degree blade angle. Since