Airworthiness Directive · Amendment 39-21316 · Main rotor gearbox
Airbus Helicopters
This AD applies to Airbus Helicopters Model AS350B, AS350B1, AS350B2, AS350B3, AS350BA, AS350D, AS350D1, AS355E, AS355F, AS355F1, AS355F2, AS355N, AS355NP, EC130B4, and EC130T2 helicopters, all serial numbers, certificated in any category.
The FAA is adopting a new airworthiness directive (AD) for Airbus Helicopters Model AS350B, AS350B1, AS350B2, AS350B3, AS350BA, AS350D, AS350D1, AS355E, AS355F, AS355F1, AS355F2, AS355N, AS355NP, EC130B4, and EC130T2 helicopters. This AD requires visually inspecting each main rotor gearbox (MGB) suspension bar attachment bracket bolt for missing bolt heads. Depending on the outcome of the visual inspection, measuring the tightening torque, removing certain parts, sending photos and reporting information to Airbus Helicopters, and completing an FAA-approved repair is required. This AD was prompted by a report of a missing MGB suspension bar attachment bolt head. The actions of this AD are intended to address an unsafe condition on these products.
You are responsible for performing each action required by this AD within the specified compliance time unless it has already been accomplished prior to that time.
For helicopters with less than 1035 hours time-in-service (TIS), before reaching 1200 hours TIS, and for helicopters with 1035 or more hours TIS, within 165 hours TIS or 12 months, whichever occurs first, visually inspect each MGB suspension bar attachment bracket bolt for missing bolt heads by following the Accomplishment Instructions, paragraph 3.B.2.a. of Airbus Helicopters Alert Service Bulletin (ASB) No. AS350-05.00.92, Airbus Helicopters ASB No. AS355-05.00.79, or Airbus Helicopters ASB No. EC130-05A028, all Revision 0 and dated July 16, 2018 (ASB AS350-05.00.92, ASB AS355-05.00.79, or ASB EC130-05A028), as applicable to your model helicopter. If any bolt heads are missing, do the following:
(1) If one bolt head is missing, do the actions under the section “If only one screw head (a) is missing” in the Accomplishment Instructions, paragraph 3.B.2.b of ASB AS350-05.00.92, ASB AS355-05.00.79, or ASB EC130-05A028, as applicable to your model helicopter, except you are not required to return removed parts to Airbus Helicopters. You must do the repair before further flight, and you must submit the photographs and reply form to Airbus Helicopters within 30 days of completing the inspection.
(2) If two or more bolt heads are missing, before further flight, repair using a method approved by the Manager, Rotorcraft Standards Branch. For a repair method to be approved by the Manager, Rotorcraft Standards Branch, as required by this paragraph, the Manager's approval letter must specifically refer to this AD.
Note 1 to paragraph (e): Airbus Helicopters refers to the bolts as screws.
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.
