AD 2012-05-01 Airworthiness Directives; Eurocopter France Model Helicopters

This AD becomes effective April 24, 2012.

(1) The Manager, Safety Management Group, DOT/FAA Southwest Region, FAA, may approve AMOCs for this AD. Send your proposal to: Gary Roach, ASW-111, Aviation Safety Engineer, Rotorcraft Directorate, Regulations and Guidance Group, 2601 Meacham Blvd., Fort Worth, Texas 76137, telephone (817) 222-5130, fax (817) 222-5961, email gary.b.roach@faa.gov. (2) For operations conducted under a Part 119 operating certificate or under Part 91, Subpart K, we suggest that you notify your principal inspector, or lacking a principal inspector, the manager of the local flight standards district office or certificate holding district office, before operating any aircraft complying with this AD through an AMOC.

(1) The Eurocopter EASB contains four different EASB numbers; three (Nos. 62.00.24, 62.14, and 65.45) apply to different civil Eurocopter model helicopters; and one (No. 62.00.10) only applies to non-FAA type-certificated military Model 565 helicopters and is not incorporated by reference. You may review a copy of the referenced service information at the FAA, Office of the Regional Counsel, Southwest Region, 2601 Meacham Blvd., Room 663, Fort Worth, Texas 76137. (2) The subject of this AD is addressed in European Aviation Safety Agency Emergency AD No. 2006-0362-E, dated November 30, 2006.

(1) For a main rotor head frequency adapter, pre MOD 0762C39, within 110 hours time-in-service (TIS), remove the main rotor blades, modify the frequency adapters and bushes, and change the part number of the frequency adapter as shown in Figures 1 through 5 and by following the Accomplishment Instructions, paragraph 2.B.2., of Eurocopter Emergency Alert Service Bulletin (EASB) No. 62.00.24 for the Model SA-365N, N1, AS-365N2, and AS 365 N3; No. 62.14 for the Model SA-366G1; and No. 65.45 for the Model SA-365C, C1, and C2 helicopters; all dated November 23, 2006. This modification is MOD 0762C39. (2) For each main rotor head frequency adapter modified per MOD 0762C39, within 10 hours TIS, unless accomplished previously, and thereafter at intervals not to exceed 10 hours TIS, inspect to determine whether the safety wire is in place on the trailing edge of the frequency adapter and whether the holes in the frequency adapters and the frequency adapter bushes, as shown in Figure 5 of the EASB for your model helicopter, are blocked. (i) If the lockwire is missing from the trailing edge of the frequency adapter, before further flight, reposition the bush if it has turned and install more safety wire. (ii) If a hole is blocked, before further flight, unblock the hole. (3) Before installing a frequency adapter or bush, modify the frequency adapter or bush and change the part number in accordance with paragraph (e)(1) of this AD.

This AD defines the unsafe condition as deterioration and failure of Starflex star arm ends. These deteriorations generated high-amplitude vibrations in flight requiring precautionary landings. These deteriorations are due to the strong effect of temperature on the strength of the bush-to-Starflex star arm end attachment and require modification of the frequency adapters and the frequency adapter bushes to improve the ventilation in the area on the star arm end. This condition could result in failure of the star arm end, severe vibration, and subsequent loss of control of the helicopter.