AD 75-17-25

75-17-25 SOCIETE NATIONALE INDUSTRIELLE AEROSPATIALE: Amendment 39- 2330. Applies to Model SA-341G "Gazelle" helicopters, certificated in all categories, with main rotor shaft P/N 341A.31.0001, dot number .05 and lower, in which Aerospatiale Modification No. AMS 07.6072 has not been incorporated.

Compliance is required within the next 100 hours' time in service after the effective date of this AD, unless already accomplished in accordance with Gazelle Service Bulletin No. 05.04.

To prevent possible rotation of the main rotor head swashplate upper bearing, accomplish the following:

(a) Inspect the spigot of upper bearing stop P/N 341A.31.4236.20 for evidence of rotation of the upper bearing in accordance with subparagraph 1C(1) of Gazelle Service Bulletin No. 05.04, dated March 9, 1973, or an equivalent approved by the Chief, Aircraft Certification Staff, FAA, Europe, Africa, and Middle East Region, c/o American Embassy, APO New York 09667.

(b) If evidence of upper bearing rotation is found, remove the main rotor shaft P/N 341A.31.0001 and replace with a serviceable part of the same part number upon which Aerospatiale Modification No. AMS 07.6072 has been incorporated.

(c) If no evidence of upper bearing rotation is found, install a second upper bearing stop P/N 41A.31.4236.20 in accordance with subparagraph 1C(2) of Gazelle Service Bulletin No. 05.04, dated March 9, 1973, or an equivalent approved by the Chief, Aircraft Certification Staff, FAA, Europe, Africa, and Middle East Region, c/o American Embassy, APO New York 09667.

This amendment becomes effective August 20, 1975.