Summary
This document proposes to revise an earlier proposed airworthiness directive (AD) that would have required replacing the washers on the attachment bolts of the lower fitting of the main landing gear (MLG) on certain Pilatus Britten-Norman Ltd. (Pilatus Britten-Norman) BN-2, BN-2A, BN-2B, and BN-2T series airplanes. The proposed AD was the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for the United Kingdom. The actions specified by the proposed AD are intended to prevent the bolts that attach the lower fitting of the MLG to the nacelle from becoming threadbound, which could result in structural failure of the MLG with consequent loss of control of the airplane during takeoff, taxi, or landing operations. Since issuing the NPRM, the Federal Aviation Administration (FAA) has realized that the Model BN-2T-4R airplanes were inadvertently omitted from the proposed AD. In addition, Pilatus Britten-Norman has revised the service information to include replacing the attachment bolts and nuts of the lower fitting of the MLG instead of re-using the existing bolts and nuts. This service information also adjusts the torque values of the nuts. The FAA has determined that the procedures included in the revised service information should be incorporated into the proposed AD, and that the comment period for the proposal should be reopened and the public should have additional time to comment.