Service and Testing Observations of Fatigue Failure in Helicopter Components

FATIGUE failure is now one of the most serious hindrances to satisfactory service life for helicopters.

To help the industry bring the fatigue failure problem under control, these authors summarize what they have learned from studying 169 fatigue failures that occurred during 58,000 hr of helicopter flying operations.

They have classified these failures as being caused by:

1. 1.
   Design error.
2. 2.
   Manufacturing error.
3. 3.
   Field error.

They discuss specific examples in each group and what was done to correct the cause of the failure.