AD 80-14-15

80-14-15 SOCIETE NATIONALE INDUSTRIELLE AEROSPATIALE (SNIAS): Amendment 39-3833. Applies to Model AS-350 series helicopters with flange, P/N 350A371201-20 installed, certificated in all categories.

To prevent the failure of flange P/N 350A371201-20, accomplish the following:

(a) Within the next five hours time in service after the effective date of this AD, and thereafter at intervals not to exceed 25 hours time in service from the last inspection until a steel flange P/N 350A371207-20 is installed, inspect the flange P/N 350A371201-20 for cracks using the dye penetrant method as follows:

(1) Remove the vibration damper in accordance with Aerospatiale Maintenance Work Card 65.12.403, dated February 1979, or an FAA-approved equivalent. Do not remove flange.

(2) Clean the flange P/N 350A371201-20 with soapy water and a non-metallic brush.

(3) Apply the dye penetrant to the flange blending radius to the cylindrical section, being careful to protect the adjacent areas against splashing.

(b) If, during an inspection required by paragraph (a) or (d) of this AD, no cracking is found, reinstall the vibration damper in accordance with Aerospatiale Maintenance Work Card 65.12.403, dated February 1979, or an FAA-approved equivalent, return the assembly to service, and continue to inspect in accordance with paragraph (a) or (d) of this AD, as appropriate.

(c) If, during an inspection required by paragraph (a) or (d) this AD, cracking is found, before further flight -

(1) Replace the flange in accordance with Aerospatiale Maintenance Work Card 65.12.401, dated June 1977, or an FAA-approved equivalent, with a crack-free new or serviceable used flange of the same part number and accomplish the repetitive inspection required by paragraph (d) of this AD. (Before installation of a used flange, inspect it in accordance with the method specified in paragraph (a) of this AD to ensure that it is crack-free); or

(2) Install a steelflange, P/N 350A371207-20 (also identified as modification AMS 6063).

(d) Within the next 25 hours time in service after flange replacement in accordance with paragraph (c)(1) of this AD, and thereafter at intervals not to exceed 25 hours time in service from the last inspection, inspect flange P/N 350A371201-20 in accordance with the method specified in paragraph (a) of this AD.

(e) Upon installation of a steel flange P/N 350A371207-20, inspections required by paragraphs (a) and (d) of this AD may be discontinued.

(f) For purposes of this AD, an FAA-approved equivalent must be approved by the Chief, Aircraft Certification Staff, FAA, Europe, Africa, and Middle East Office.

NOTE: SNIAS (Aerospatiale) Mandatory Service Bulletin 05-03, dated May 10, 1979, pertains to this same subject.

This amendment becomes effective July 3, 1980, as to all persons except those persons to whom it was made immediately effective by the telegram issued April 23, 1979, which contained this amendment.