Eurocopter’s ubiquitous light single, the AS350B3e Ecureuil/AStar, is subject to airspeed limits and repetitive inspections as a result of an early-October emergency service bulletin and accompanying airworthiness directive (AD). The helicopter is now limited to 100 knots airspeed at sea level to reduce dynamic loads on the tail rotor. In addition, repetitive inspections must be conducted, with maximum intervals of three flight hours, on the laminated half-bearings.
The emergency AD was prompted by the fatal crash of a B3e in Guatemala in late September. Investigators are said to be focusing on deterioration of the half-bearings and an in-flight failure of the tail rotor. Eurocopter has devised a procedure to assist the pilot in case of in-flight vibration in the pedals.
Operators are feeling the effects of the temporary requirements. “The business case for the flat-rate services we provide has been degraded,” Pascal Brun, a pilot at Chamonix Mont-Blanc Hélicoptères in the French Alps, told AIN. He has been operating one B3e since March 2012, at an average utilization of nearly 1,000 flight hours per year. About 80 percent of the operations are for aerial work.
Vne at 10,000 feet has been reduced to 86 knots from 125 knots. This impedes productivity, as Brun previously descended from high altitudes back to base at close to Vne. Eurocopter is planning to retrofit the fleet between February and July. Retrofitted helicopters won't need the inspections any more.