Final Report: Manufacturing flaw LED to rotor blade crack

Aviation International News » August 2010
August 2, 2010, 10:37 AM

Bell 206L-3, Abilene, Texas, March 29, 2009–The NTSB determined the fatigue crack in the trailing edge of a main rotor blade was caused by interconnected porosity and resulting corrosion resulting from an undetected manufacturing defect. During a post-flight inspection following a flight in turbulence, the pilot noted the crack in the blade. Examination of the damage revealed a path of interconnected porosity between the lower trailing-edge skin, trailing-edge strip and epoxy that allowed moisture penetration and eventual corrosion. According to Bell Helicopter, while trailing-edge blade cracks are rare, they can usually be detected as a one-per-revolution vibration in flight, and are identified during post-flight inspection while attempting to diagnose a rotor imbalance.

Share this...

Please Register

In order to leave comments you will now need to be a registered user. This change in policy is to protect our site from an increased number of spam comments. Additionally, in the near future you will be able to better manage your AIN subscriptions via this registration system. If you already have an account, click here to log in. Otherwise, click here to register.