Monday, January 3, 2011
Safety Rules & Regulations
The FAA has issued an Emergency Airworthiness Directive for Schweizer Model 269A, A 1, B, C, C-1 and Th-55 series helicopters.
The Emergency AD is prompted by a locknut working loose on the tailboom aft cluster fitting strut. Further investigation revealed that the locknut installed on the expandable bolt did not have the proper threads. This condition, if not corrected, could result in the strut and driveshaft separating from the helicopter and subsequent loss of control of the helicopter.
The FAA said an unsafe condition is likely to exist or develop in other helicopters of these same type designs.
The AD requires, before further flight, removing the locknut, part number MS21043-3. Reinstalling the locknut while determining the locknut drag torque is then required. If the drag torque is a minimum of 2 in-lbs, re-torquing the locknut to 23 in-lbs is required. If the drag torque is not at least 2 in-lbs, replacing the locknut with an airworthy locknut is required.
FAA Issues Emergency AD For Piaggio P-180 aircraft
The EAD is prompted by flight controls jamming on Piaggio Model P-180s.
EASA and the FAA previously issued airworthiness directives that required correcting the fuselage drain system and ensuring that the drain lines of the environmental unit condenser were not clogged. Since the ADs became effective, the FAA received information on two additional incidences where Piaggio Model P-180s had water accumulation in the belly of the fuselage that froze and caused the flight controls to jam.
The EAD requires an immediate functional test of the fuselage drain holes and a report of the results to the FAA.
The FAA is working with EASA and Piaggio on this unsafe condition. Due to the nature of the immediate safety of flight situation, the FAA is working this AD concurrently with EASA instead of waiting for EASA, as the State of Design, to issue an AD. Thus, this action is considered unilateral AD action.
The FAA is issuing this AD since it was determined the unsafe condition described previously is likely to exist or develop in other products of the same type design.
The FAA says this AD is considered an interim action.