# AD 70-13-01: Razor Socket Supply Transformer

- Type: Airworthiness directive
- Status: Current
- Products: Airbus BAC 1-11 200 Series and BAC 1-11 400 Series
- Effective: July 13, 1970
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Amendment: 39-1012
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/1A3125FB89D47F27862569A400630A81.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/70-13-01

## The airworthiness directive

70-13-01 BRITISH AIRCRAFT CORPORATION: Amdt. 39-1012. Applies to Models BAC 1-11 200 and 400 series airplanes having razor socket supply transformer P/N RD.10590 installed.

To prevent overheating of the razor socket supply transformer when a non-compatible electrical appliance is connected into a razor socket, within the next 1500 hours' time in service after the effective date of this AD, unless already accomplished, accomplish either of the following:

  (a) De-activate the razor sockets by disconnecting, insulating, and tying back the socket supply cable from the appropriate circuit breaker and fitting a locking clamp to the circuit breaker knob; or

  (b) Modify the razor socket circuit to provide a 1/4 ampere fuse in the positive line of the rectified output of the transformer in accordance with British Aircraft Corporation Model BAC 1-11 Service Bulletin No. 25-PM4458 dated February 9, 1970, or a later ARB-approved issue, or an FAA-approved equivalent.

(British Aircraft Corporation Model BAC 1-11 Service Bulletin No. 25-A-PM4458 refers to this subject.)

This amendment becomes effective July 13, 1970.

## 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.

Its text cites no advisory circulars or STCs.

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