Siam Hiller Holdings, Inc. Receives Airworthiness Directive Amendment for UH-12 Helicopters

Summary

The Federal Aviation Administration has adopted a new airworthiness directive for Siam Hiller Holdings, Inc. Model UH-12 helicopters, requiring the replacement of undrilled-shank bolts with drilled-shank bolts and the installation of castellated nuts and cotter pins to prevent control system separation and loss of helicopter control.