Airworthiness Directive · Amendment 39-16455 · Eurocopter France Model SA-365N, SA-365N1, AS-365N2, AS-365N3, SA-366G1, EC 155B, EC155B1, SA-365C, SA-365C1, SA-365C2, SA-360C Helicopters
Eurocopter France Model SA-365N, SA-365N1, AS-365N2, AS-365N3, SA-366G1, EC 155B, EC155B1, SA-365C, SA-365C1, SA-365C2, SA-360C Helicopters
Model EC 155B, EC155B1, SA-360C, SA-365C, SA-365C1, SA-365C2, SA-365N, SA-365N1, AS-365N2, AS 365 N3, and SA-366G1 helicopters, certificated in any category.
This amendment supersedes an existing airworthiness directive (AD) for the specified Eurocopter France (Eurocopter) helicopters. That AD requires repetitively inspecting the main gearbox (MGB) planet gear carrier for a crack and replacing any MGB that has a cracked planet gear carrier before further flight. This action requires the same inspections required by the existing AD, but shortens the initial inspection interval. This AD is prompted by the discovery of another crack in a MGB planet gear carrier and additional analysis that indicates that the initial inspection interval must be shortened. The actions specified by this AD are intended to detect a crack in the web of the planet gear carrier, which could lead to a MGB seizure and subsequent loss of control of the helicopter.
| For a main gearbox (MGB) that has: | Inspect: |
|---|---|
| (1) Less than 250 hours time-in-service (TIS) since new or last overhaul. | On or before the MGB reaches 35 hours TIS, unless accomplished previously, and thereafter at intervals not to exceed 50 hours TIS. |
| (2) 250 or more hours TIS since new or last overhaul. | Within 15 hours TIS, unless accomplished previously, and thereafter at intervals not to exceed 50 hours TIS. |
To detect a crack in the web of the planet gear carrier, which could lead to a MGB seizure and subsequent loss of control of the helicopter, accomplish the following:
(a) Either borescope inspect the web of the MGB planet gear carrier for a crack in accordance with the Operational Procedure, paragraphs 2.B.2. through 2.B.2.a.1, of Eurocopter Emergency Alert Service Bulletin (EASB) No. 05A007, Revision 2; No. 05.00.48, Revision 3; No. 05.26, Revision 2; or No. 05.33, Revision 2; as applicable to your model helicopter, or visually inspect the MGB planet gear carrier in accordance with the Operational Procedure, paragraphs 2.B.3. through paragraph 2.B.3.a.1, of the EASB applicable to your model helicopter. Each EASB at the stated revision level is dated November 16, 2009.
(b) If a crack is found in the planet gear carrier, replace the MGB with an airworthy MGB 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 Manager, Safety Management Group, FAA, Attn: Gary Roach, Aviation Safety Engineer, Rotorcraft Directorate, FAA, 2601 Meacham Blvd., Fort Worth, Texas 76137, telephone (817) 222-5130, fax (817) 222-5961, for information about previously approved alternative methods of compliance.
(d) The Joint Aircraft System/Component (JASC) Code is 6320: Main Rotor Gearbox.
