Learjet 40/45 Main Landing Gear Actuator End Caps Advisory Wire 32-053
Heroux, the component manufacturer, and Bombardier were recently given reason to question the load testing that was originally accomplished on the Learjet 45 Main Landing Gear (MLG) Actuator during certification. This occurred while accomplishing ongoing testing. Fatigue testing was re-performed and resulted in the need to lower the life limit of the actuator end caps.
Please note no issues with the end caps have been reported from in-service aircraft.
Three (3) samples of 45 MLG actuators have been retested and resulted in the need to reduce the end cap life limit. The end cap current life is 17,000 landings. The new life limit will be lowered to 2,387 landings for FAA governed aircraft and 1,988 landings for EASA governed aircraft. There will be a grace period of 25 landings beyond the current number of landings, but only for those actuators that are already beyond the new life limit. No other extensions are available at this time.
ACTION: See attached Action Wire