AD FAA-2006-26044

The FAA is adopting a new airworthiness directive (AD) for all Fokker Model F.28 Mark 1000, 2000, 3000, and 4000 airplanes. This AD requires a one-time inspection of the left- and right-hand main landing gear (MLG) downlock actuators or a review of the airplane maintenance records to determine the part number of each downlock actuator installed, and replacement of identified MLG downlock actuators with modified MLG downlock actuators. This AD results from a report of a failed downlock actuator, which resulted in the left MLG collapsing during taxi after landing. We are issuing this AD to prevent failure of the downlock actuator, which could prevent the MLG side stay from locking properly, resulting in collapse of the MLG during ground maneuvers or upon landing.