THE US FEDERAL Aviation Administration is placing highly restrictive airworthiness directives (AD) on Robinson Helicopter R22 and R44 light helicopters in an effort to prevent mast-bumping and rotor/fuselage strikes.
Its actions stop well short, however, of the grounding recommended by the US National Transportation Safety Board (NTSB) pending investigation of the type's accident record (Flight International, 18-24 January).
The FAA says: "If there were a design flaw, we would have grounded them before now. But that is not the case, since the majority of the helicopters are flying safely."
The new AD requires R22 and R44 operators to:
limit forward airspeed to the minimum possible, with 80kt (150km/h) the maximum allowable in turbulence;
restrict flight operations to the lowest safe density altitude;
avoid turbulence;
maintain balanced flight;
face into wind when hovering out-of-ground effect;
stay grounded where surface winds exceed 25kt, gusts exceed 15kt, or windshear or turbulence is forecast.
Robinson-developed aircraft-component modifications will undergo FAA tests starting in April, says the FAA. Meanwhile, its Flight Standards Branch is developing new requirements for R22 and R44 pilot training.
Source: Flight International
