Failure of a helicopter rotor

The vital part of a helicopter is no doubt the main rotor. If the rotor fails, the helicopter will fall. Therefore rotor blades are checked very carefully and replaced or repaired if they show any indication of damage which might lead to failure. A case is reported where a rotor blade failed after a long service time without any prior indications of damage. The failure analysis showed that the origin of the failure dates far back into the early lifetime of the rotor blade. The material properties connected with crack initiation, crack propagation and fracture were measured and are discussed. A proposal is made for detection of cracks before they have grown to a critical size.

Keywords:

• Failure Analysis
• Helicopter
• Fracture
• Rotor Blade
• Fatigue Crack Growth