75-27-06 PILATUS AIRCRAFT LTD: Amendment 39-2478. Applies To Pilatus Model PC-6 airplanes, serial numbers 685 and below (all variants) manufactured by Pilatus Aircraft Ltd., powered by Lycoming GSO-480-B1A6 engines.
NOTE: This AD does not apply to Pilatus PC-6 airplanes manufactured by Fairchild Hiller.
Compliance is required within the next 100 hours time in service after the effective date of this AD, unless already accomplished.
To prevent hazardous fuel leaks from developing at the elbow fittings connecting the fuel line to the fuel pump and carburetor and to prevent a broken fuel line, accomplish the following:
(a) Replace aluminum fittings (AN 822-8D and AN 823-8D) with stainless steel fittings (MS 20822-8C and MS 20823-8C), or FAA-approved equivalents.
(b) Replace aluminum fuel line P/N 6238.0094.80 with a stainless steel fuel line P/N 6238.0094.80C, or an FAA-approved equivalent.
This amendment becomes effective on January 19, 1976.