# AD 75-27-06: Fuel Leak Fittings

- Type: Airworthiness directive
- Status: Current
- Products: Pilatus PC-6, PC-6-H1, PC-6-H2, PC-6/350, PC-6/350-H1, PC-6/350-H2, PC-6/A, PC-6/A-H1, PC-6/A-H2, PC-6/B-H2, PC-6/B1-H2, PC-6/B2-H2 and 2 more
- Effective: January 19, 1976
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Small airplane
- Amendment: 39-2478
- Registered aircraft: 11 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/372DDFE14B18FD3786256A45006F7769.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/75-27-06

## The airworthiness directive

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.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS 7A15](https://openairdocs.org/tcds/7A15): Pilatus Aircraft Ltd.; names 14 of 15 models: PC-6/B2-H2, PC-6/350-H1, PC-6/C1-H2, PC-6/B-H2, PC-6/A-H2, PC-6/C-H2, PC-6, PC-6/A-H1…

## Registered aircraft it may apply to (OpenAirDocs)

Matched by airframe and engine model; the AD's applicability may narrow it by serial number, part number or equipment.

- Aircraft: 11 (11 by airframe model, 0 by engine model)
- Makers: Pilatus 11

Models with the most aircraft:

- [Pilatus PC-6/B2-H2](https://openairdocs.org/model/pilatus-pc-6-b2-h2): 8 aircraft (airframe model)
- [Pilatus PC-6/B1-H2](https://openairdocs.org/model/pilatus-pc-6-b1-h2): 2 aircraft (airframe model)
- [Pilatus PC-6](https://openairdocs.org/model/pilatus-pc-6): 1 aircraft (airframe model)

All 3 models: https://openairdocs.org/ad/75-27-06/models.md
Every aircraft: https://openairdocs.org/ad/75-27-06/aircraft.md

Its text cites no advisory circulars or STCs.

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