AD 73-09-03

73-09-03 SOCIETE NATIONALE INDUSTRIELLE AEROSPATIALE: (S.N.I.A.S.) - formerly SUD Aviation). Amendment 39-1626. Applies to Lama Model SA-315B and Alouette Models SA-316B, SA-316C, and SA- 319B helicopters having main gear box P/N's 319A.62.00.000.1 and .2, serial numbers up to and including 2,000, installed.

Compliance required as follows, unless already accomplished:

(1) For helicopters that have accumulated 500 or more hours' time in service on the main rotor gear box since new or since overhauled, compliance is required before further flight, except that the aircraft may be flown in accordance with FAR 21.197 to a base where the work can be performed.

(2) For all other helicopters, compliance is required before the accumulation of 500 hours' time in service on a main rotor gear box since new or since overhauled.

To prevent the possible failure of a main rotor gear box because of defective planetary gears, remove and disassemble gear box P/N's 319A.62.00.000.1 or .2 and inspect the planet pinions of the second stage planetary gear, P/N 3160S.62.05.208, for cracks and evidence of overheat, due to grinding, in accordance with the inspection procedures specified in Aerospatiale Service Letter No. 137-01-72, dated November 30, 1972, or an FAA-approved equivalent and -

(a) For Lama Model SA-315B helicopters, Aerospatiale Service Bulletin No. 05-02, dated October 27, 1972, as amended on November 30, 1972, or an FAA-approved equivalent; and

(b) For Alouette Models SA-316B, SA-316C and SA-319B helicopters, Aerospatiale Service Bulletin No. 05-47, dated October 27, 1972, or an FAA-approved equivalent.

(c) If cracks or evidence of overheat are found in the planet pinions of the second stage planetary gear, P/N 3160S.62.05.208, replace with serviceable planet pinions of the same part number.

This amendment is effective upon publication in the Federal Register as to all persons except those persons to whom it was made immediately effective by the airmail letter dated March 23, 1973, which contained this amendment.