Airworthiness Directive · Amendment 39-13686 · Eurocopter Deutschland Model MBB-BK 117 A-1, A-3, A-4, B-1, B-2, and C-1 Helicopters
Eurocopter Deutschland Model MBB-BK 117 A-1, A-3, A-4, B-1, B-2, and C-1 Helicopters
Model MBB-BK 117 A-1, A-3, A-4, B-1, and B-2, all serial numbers (S/N), and Model C-1, S/N 7500 through 7545, certificated in any category.
This amendment adopts a new airworthiness directive (AD) for the specified Eurocopter Deutschland (ECD) model helicopters that requires inspecting the vertical fin skin paneling to determine if it was manufactured with the correct wall thickness. This amendment 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 AD are intended to prevent failure of the vertical fin and subsequent loss of control of the helicopter.
To prevent failure of the vertical fin and subsequent loss of control of the helicopter, do the following:
(a) Using external calipers, measure the wall thickness, including primer coating, of the skin paneling of the vertical fin at the locations shown in Figure 1 of this AD.
Note 1: Eurocopter Deutschland (ECD) Alert Service Bulletin No. ASB-MBB-BK117-30-109, Revision 1, dated July 3, 2003, pertains to the subject of this AD.
(b) If the wall thickness, including the primer coating, of the paneling is less than 0.778 millimeter (0.03063 inch) at any of the measured locations, replace the vertical fin with an airworthy part before further flight.
(c) To request a different method of compliance or a different compliance time for this AD, follow the procedures in 14 CFR 39.19. Contact the Safety Management Group, Rotorcraft Directorate, FAA, for information about previously approved alternative methods of compliance.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
