Raytheon has issued a "safety communication" to Premier I operators advising careful deployment of the landing flaps after US Federal Aviation Administration concerns were raised over the use in the flap actuators of the same brittle-prone steel that resulted in the recent grounding of the Learjet 45 fleet.
Raytheon's advisory, which may be followed by an FAA airworthiness directive, instructs operators to reduce instantaneous structural loads on the flaps by deploying them in 10° increments to their full angle of 30°. The device is made from the same stainless steel that suffered from hydrogen embrittlement in the Learjet 45 actuator assembly.
The manufacturer says it has "sent a team" to the maker of the unit, MPC Products of Skokie, Illinois to evaluate options.
Source: Flight International
