The FAA is proposing an airworthiness directive for the Agusta A109E and A109S based on cases of damage to the main drive shaft caused by improperly secured metallic spacers. The AD would require a one-time inspection of the lower semichannel assemblies to determine proper installation of the metallic spacers on the semichannels and for the correct seating of the gaskets. The FAA is taking comments until July 23.
The FAA issued a second Emergency Airworthiness Directive [2012-10-53] for the Eurocopter EC135 on May 18. This EAD supercedes the earlier EAD [2012-10-51] for an inspection of the main rotor hub shaft flange for cracks.
The EASA has issued a new emergency Airworthiness Directive (AD) after further cracks were detected on the lower hub-shaft flange of two other Eurocopter EC135 light-twin helicopters. Repetitive preflight inspections are required and different from those described in a first emergency AD, issued in March. The initial inspections proved insufficient. The investigation is ongoing.
The FAA is adopting an airworthiness directive for certain Pratt & Whitney Canada PT6A-38, -41, -42, -42A, -61, -64, -66, -66B, -110, -112, -114, -114A, -121, -135, and -135A series turboprop engines. The AD requires the removal from service of certain PMA replacement parts from Timken Alcor Aerospace Technologies, including first-stage sun gears and planet gears installed in the reduction gearbox. This AD was prompted by failures of certain first-stage sun gears manufactured by Timken Alcor.
The FAA has issued an Airworthiness Directive for the Bombardier CL-600-2B16 (Challenger 604) prompted by multiple reports of short-circuit events during pre-delivery inspections and test flights. One event resulted in smoke in the cockpit. The AD requires replacing or relocating certain circuit-breaker panel bus bars, inspecting for any loose or improperly crimped lugs and replacement if necessary, and inspecting for foreign object damage in certain areas.
The FAA has issued an Airworthiness Directive for Learjet 45s prompted by changes to the Airworthiness Limitations Section of the maintenance manual that add life limits, revise life limits or add inspections. The AD requires revising the maintenance program to include new or more restrictive life limits and inspections.
Prompted by two incidents of mis-routed fire extinguisher wires, the FAA has issued an Airworthiness Directive [AD 2012-08-16] for several Learjet 60 models.The AD requires the inspection of electrical leads routed to the fire extinguishing containers for proper identification and to ensure the electrical leads are connected to the correct squibs.
The FAA has issued an Airworthiness Directive for the Bell 206L, 206L-1, 206L-3 and 206L-4 prompted by two accidents in which investigations revealed a main rotor blade failed because of fatigue cracking. Transport Canada advises there is no reliable inspection method to detect the cracks before blade failure and has reduced the life limit from 3,600 to 1,400 hours’ time-in-service.
The FAA has issued what could be an expensive tail-boom inspection airworthiness directive for the more than 100 Eurocopter EC130B4s in service in the U.S., most of them with air-tour operators. The AD mandates inspections for cracks in the region where the tail boom meets the fenestron assembly. If cracks are found the boom must be replaced at an estimated cost of $64,250 per helicopter.