Following a similar directive from Transport Canada, the FAA yesterday issued an emergency airworthiness directive requiring the removal and replacement of certain main rotor hub strap pins on select Bell 204, 205, and 212 models before further flight. The emergency AD follows the fatal crash of a Bell 212 last week in Canada.
Canada TSB investigators determined that the pin on that helicopter failed, leading to the detachment of the rotor hub and main rotors in flight. The pin had only 20 hours of service. An inspection of another Canadian-registered 212 found another pin was deformed with only 29 hours time in service. Affected pins are identifiable with the serial number prefix “FNFS” and can be installed in Bell 204B, 205A-1, 205B, and 212 helicopters.
In an alert service bulletin published July 5, Bell said the pin “may have not been manufactured in accordance with the engineering design requirements and may shear as a result of the non-conformance.” The AD impacts approximately 400 helicopters worldwide. Bell said replacing all four pins would require 20 manhours of labor.
The accident helicopter was a 1979 Bell 212 owned and operated by Yellowhead Helicopters. It was being flown on a fire-suppression support mission transporting fire crews near Evansburg, Alberta, and crashed in a remote area not accessible by road. Pilot Heath Coleman, the sole occupant, was killed. Bell 204, 205, and 212 models are widely used for both fire crew transport and water bombing.