Airworthiness Directives; Eurocopter Deutschland Model MBB-BK 117 A-1, A-3, A-4, B-1, B-2, and C-1

This document proposes adopting a new airworthiness directive (AD) for the specified Eurocopter Deutschland (ECD) model helicopters. This proposal would require inspecting the vertical fin skin paneling to determine if it was manufactured with the correct wall thickness. This proposal is prompted by a report from the manufacturer that some vertical fins may have been produced with the wrong vertical fin skin thickness. The actions specified by this proposed AD are intended to prevent failure of the vertical fin and subsequent loss of control of the helicopter.

Agency Contact: Richard Monschke, Aviation Safety Engineer, FAA, Rotorcraft Directorate, Rotorcraft Standards Staff, Fort Worth, Texas 76193-0110, telephone (817) 222-5116, fax (817) 222-5961.