NOTAR Failure Grounds Explorers

Specialist Aviation Services recalled all 18 of its MD Helicopters MD-902s from police and emergency medical service lessees while it investigated the control system failure. On Aug. 8, an SAS Explorer on lease to Great North Air Ambulance of Durham, England, executed a run-on landing at its Denham Airfield base outside of London after the pilot experienced what the operator described as a dramatic reduction in yaw control. Post-landing, SAS inspectors found a cable-and-rod assembly between the aircraft's anti-torque pedals and the rotating cone on its no-tail-rotor (NOTAR) system was broken. SAS notified MD, which issued Service Bulletin SB900-108 Aug. 12, covering MD900-series aircraft with serial numbers 900-00008 through 900-00128 and requiring, before further flight, a fluorescent magnetic particle inspection of the forward directional control cable and modification to the rotating-cone control rod. SAS said it would return five of its Explorers to service today and would have all 18 flying again by tomorrow. For related news