# AD 77-21-08: Auxiliary Fuel System

- Type: Airworthiness directive
- Status: Current
- Products: Airbus BAC 1-11 200 Series and BAC 1-11 400 Series with STC SA2971WE
- Effective: January 31, 1978
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Amendment: 39-3129
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/92D797ABF86CB461862569A50070A2A3.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/77-21-08

## The airworthiness directive

77-21-08 BRITISH AIRCRAFT CORPORATION: Amendment 39-3062 as amended by Amendment 39-3129. Applies to BAC 1-11 airplanes certificated in all categories incorporating auxiliary fuel tanks per supplemental type certificate SA2971WE.

Compliance required as indicated.

To prevent possible fuel leakage into the cargo compartment which may result in a fire or explosion accomplish the following:

  (a) Before further flight after the effective date of this AD, do not add fuel to the auxiliary fuel tanks installed per STC SA2971WE.

  (b) Within 12 hours time in service after the effective date of this AD, unless already accomplished, accomplish either (1) or (2):

  (1) Deactivate the auxiliary fuel system as follows:

    (i) Purge all auxiliary fuel tanks.

    (ii) Close all auxiliary fuel tanks and fuel vent valves.

    (iii) Disconnect auxiliary tank electrical connectors and secure wiring.

    (iv) Pull all auxiliary fuel tank circuit breakers in thecockpit to the off position and lock out with a positive device.

    (v) Make entry in the log book.

    (vi) Placard cockpit auxiliary fuel panel inoperative.

NOTE: National Aircraft Leasing Report TA 4-2 dated September 1, 1977 is an acceptable procedure for deactivation.

  (2) Remove the auxiliary fuel system in accordance with National Aircraft Leasing Report NA 3-1060 dated September 5, 1975.

  (c) Equivalent procedures and modifications may be approved by the Chief, Aircraft Engineering Division, FAA Western Region.

  (d) The limitation required by Paragraph (a) may be removed and the deactivation or removal required by Paragraph (b) may be reactivated or reinstalled, after the auxiliary fuel system is modified in accordance with National Aircraft Leasing Service Bulletin TA-4-8 Revision "A" dated November 22, 1977 or later FAA approved revision.

Amendment 39-3062 became effective November 25, 1977 for all persons except those to whom it was madeeffective by telegram dated September 2, 1977, which contained this amendment.

This amendment 39-3129 becomes effective January 31, 1978.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS A5EU](https://openairdocs.org/tcds/A5EU): Airbus SAS; names 2 of 2 models: BAC 1-11 200 Series, BAC 1-11 400 Series

## Registered aircraft it may apply to (OpenAirDocs)

No registered aircraft matched the models it names.

## Related documents

- [STC SA2971WE](https://openairdocs.org/stc/SA2971WE): Installation of maximum 1565 gallon auxiliary fuel tanks in forward and aft cargo compartment. (1-11 SERIES 401/AK). Aircraft Tank Service Inc, Named in the applicability

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