Page:CAB Accident Report, Pacific Air Lines Flight 308.pdf/6

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There is no doubt that the No. 5 cylinder of the left engine failed and that this failure occurred only seconds after takeoff. Proof of the time of the failure lies in the fact that engine and cowl parts belonging to this engine were found on the takeoff runway after the accident occurred. The time of the failure is most important because it indicates that it occurred very soon after takeoff before any appreciable airspeed and/or altitude had been gained, and therefore narrows the field of possible corrective action which could hare been taken by the crew It 15 recognized that this engine's ring cowl was badly deformed as a result of this failure and that a section of it was displaced upward and rearward. The Board believes that the deformation of the cowling disturbed the airflow over the center section and the empennage sufficiently to cause both a severe buffet and a serious drag condition.

Conclusion

The Board therefore concludes that the pilot was unable to maintain altitude and return to the airport because of conditions beyond his control affecting the flying characteristics of the aircraft.

As a result of this acc1dent, the company decided to send its own maintenance personnel to Los Angeles to perform all future work on company aircraft.

Probable Cause

The Board determines the probable cause of this accident was that following the failure of the left engine, the left engine's ring cowl was deformed causing a buffeting and drag condition which made sustained flight impossible. A contributing factor was the scheduling of the aircraft by the company when there should have been reasonable doubt concerning the airworthiness of an engine.

BY THE CIVIL AERONAUTICS BOARD:

/s/WHITNEY GILLILLAND
Chairman:

/s/ CHAN GURNEY
Vice Chairman

/s/ G. JOSEPH MINETTI
Member

/s/ ALAN S. BOYD
Member

/s/ J S. BRAGDON
Member