Airworthiness Directives; Bell Textron Canada Limited Helicopters

The FAA proposes to adopt a new airworthiness directive (AD) for certain Bell Textron Canada Limited (BTCL) Model 407 helicopters. This proposed AD was prompted by a determination that chafing can occur at various locations on the electrical harnesses located in the aircraft instrument panel area. This proposed AD would require a one- time detailed visual inspection of the electrical harnesses for chafing and corrective actions if necessary. This proposed AD would also require rotation of the backshell cast housing of connectors of the lower engine airframe unit and installation of a wire harness bracket and support, and for certain helicopters, installation of a wire bundle sleeve. The FAA is proposing this AD to address the unsafe condition on these products.