AD 74-21-04

74-21-04 HUGHES HELICOPTERS: Amendment 39-1987 as amended by Amendment 39-2147. Applies to Hughes 269A, 269A-1, 269B, 269C Helicopters certificated in all categories, including military TH-55A equipped with canopy slat P/N 269A2297 or 269A2297-7.

Compliance required as indicated.

To detect possible cracks in canopy slat surfaces, and the condition and security of slat attachment hardware and canopy attachment areas, and provide for modification of the canopy slat, accomplish the following:

(a) On each day the helicopter is flown, conduct a close visual check by the pilot in command or an inspection by a certificated mechanic of the canopy slat surfaces over the entire length for cracks, slat attachment hardware and canopy attachment areas for condition and security. Note: The person who performs the check or inspection shall record it in the appropriate aircraft records per FAR 91.173.

(1) If cracks or other damage are found, replace prior to further flight with:

(i) P/N 269A2297 or 269A2297-7 modified in accordance with (b), below; or

(ii) P/N 269A2214; or

(iii) If the 50 hour limitation specified by (b), below, has not been exceeded, an unmodified part P/N 269A2297 or 269A2297-7 may be used, provided, it is modified at the time specified by (b), below; or

(iv) A part approved by Chief, Aircraft Engineering Division, FAA Western Region.

(b) Prior to the next 50 hours time in service after the effective date of this amendment, 39-2147, unless already accomplished, modify the canopy slat, P/N 269A2297 or 269A2297-7, in accordance with the instructions contained in Hughes Service Information Notice N-127, dated March 5, 1975, or later FAA-approved revisions, or equivalent procedure approved by the Chief, Aircraft Engineering Division, FAA Western Region.

(c) Upon installation of P/N 269A2297 or 269A2297-7 modified in accordance with (b), above, or P/N 269A2214 or other part approved by the Chief, AircraftEngineering Division, FAA Western Region, the daily visual check or inspection in accordance with (a) above may be discontinued.

Amendment 39-1987, was effective October 16, 1974, for all persons except those to whom it was made effective immediately by airmail letter dated September 23, 1974.

This Amendment 39-2147, to AD 74-21-04 becomes effective April 4, 1975.