AD 80-22-08 ACTIVE

80-22-08 SOCIETE NATIONALE INDUSTRIELLE AEROSPATIALE (SNIAS): Amendment 39-3955. Applies to Model AS 350 Series helicopters, certificated in all categories.

Compliance required as indicated, unless already accomplished.

To prevent failure of the tail rotor transmission and deterioration of the tail rotor flapping hinge bearings, which could result in loss of directional control of the helicopter, accomplish the following:

(a) Within the next 100 hours time in service after the effective date of this AD -

(1) Modify the tail rotor drive shaft assembly by incorporating Aerospatiale Modification No. AMS 350A-07-6519, or an FAA-approved equivalent.

(2) Modify the tail rotor transmission, P/N 350A-33-0006-03, by incorporating Aerospatiale Modification No. AMS 07-8519, or an FAA-approved equivalent.

(3) Incorporate paragraph 2.D, "Operating Instructions," of Aerospatiale Service Bulletin 65.13, dated November 6, 1979, or an FAA-approved equivalent, and Aerospatiale Work Card 05.23.203, page 1, dated October 1979, page 2, dated November 1979, page 3, dated November 1978, and page 4, dated November 1979, or an FAA-approved equivalent, into the helicopter maintenance manual, and perform the last flight of the day checks accordingly.

(b) For helicopters not modified in accordance with Aerospatiale Modification Nos. AMS 350A-07-6519 and AMS 07-8519 -

(1) Before further flight, except that the helicopter may be flown in accordance with FAR Section 21.197 to a base where these inspections can be performed, and thereafter following the last flight of each day:

(i) Inspect the tail rotor flapping hinge bearings, P/N 704A.33.633.038, to determine the out of flush dimension "M" of the bearing inner to outer bushing in accordance with Work Card 65.40.605, dated October 1979, of the maintenance manual, or an FAA-approved equivalent.

(ii) Inspect the tail rotor transmission, P/N 350A-33-0006-03, for evidence of oil leaks andcracks.

(2) If as a result of the determination required in paragraph (b)(1)(i) of this AD, dimension "M" is found to be less than 0.04 inches/1 millimeter, or more than 0.08 inches/2 millimeters, before further flight, replace the laminated bearing, P/N 704A-33-633-038, with a new or serviceable bearing of the same P/N, and continue the repetitive inspections of paragraph (b)(1)(i) of this AD.

(3) If as a result of the determination required in paragraph (b)(1)(i) of this AD, dimension "M" is found to be greater than 0.04 inches/1 millimeter but less than 0.08 inches/2 millimeters, return the helicopter to service and repeat the inspections required in paragraphs (b)(1)(i) of this AD.

(4) If as a result of the determination required in paragraph (b)(1)(ii) of this AD, evidence of an oil leak, or cracking is found, replace the tail rotor transmission, P/N 350A- 33-0006-03, with a serviceable tail rotor transmission which has Aerospatiale Modification AMS 07-8519 incorporated, and discontinue the repetitive inspection of paragraph (b)(1)(ii) of this AD.

(c) For all tail rotor transmissions held as spares and not already modified, install Aerospatiale Modification No. AMS 07-8519, or an FAA-approved equivalent, before installation of the tail rotor transmission on the helicopter.

(d) If an equivalent means of compliance is used in complying with paragraphs (a), (b), or (c) of this AD, that equivalent must be approved by the Chief, Aircraft Certification Staff, Europe, Africa and Middle East Office, FAA, c/o American Embassy, Brussels, Belgium.

NOTE:
1. Aerospatiale AS 350 Service Bulletin No. 65-08, revision 1, dated August 13, 1979, refers to the same subject as paragraphs (a)(2) and (c) of this AD.

2. Aerospatiale AS 350 Service Bulletin No. 65-13, dated November 6, 1979, refers to the same subject as paragraphs (a)(1), and (b)(1) of this AD.

This amendment becomes effective October 23, 1980 as to all persons except those persons to whom it was made immediately effective by telegraphic AD T79EU19, issued November 30, 1979, which contained this amendment.