Airworthiness Directive · Amendment 39-23067 · Main rotor blades
Bell Textron Canada Limited Helicopters
This AD applies to Bell Textron Canada Limited Model 407 and 427 helicopters, certificated in any category.
The FAA is adopting a new airworthiness directive (AD) for all Bell Textron Canada Limited (BTCL) Model 407 and 427 helicopters. This AD was prompted by a report that certain expandable blade bolts installed on the main rotor blade may not have received the correct heat treatment, which could result in stress corrosion cracking of the expandable blade bolts. This AD requires removing the expandable blade bolts from service and replacing them with a part eligible for installation. This AD also prohibits the installation of an affected expandable blade bolt on any helicopter. The FAA is issuing this AD to address the unsafe condition on these products.
Within 30 hours time-in-service or 30 days, whichever occurs first after the effective date of this AD, remove from service each affected part and replace with a part eligible for installation.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
