Yesterday, Transport Canada (TC) issued an emergency airworthiness directive (AD) mandating immediate inspection of collective sticks in Bell 505 turbine light single helicopters. TC took the action after Bell reported an instance of a stick and grip assembly fracturing above the cabin floor at the junction with the collective jackshaft. The fracture was discovered before engine start during the preflight check of flight controls; its exact cause is under investigation.
Over the weekend, Bell published an Alert Service Bulletin (ASB) for a one-time inspection of the controls. TC’s emergency AD makes the inspection mandatory and is considered an interim action. Per Bell’s ASB, the inspection is expected to take two man-hours and requires removal, cleaning, and inspection of the collective stick and grip assembly with a 10X magnifying glass and strong light. If a crack is suspected or detected, a further fluorescent penetrant inspection in the area of the crack is required. Unserviceable sticks must be replaced before further flight.
Bell has delivered 300 of the five-seat Model 505s since 2017.