# AD 71-16-05: Voltage Sensing Unit

- Type: Airworthiness directive
- Status: Current
- Products: Airbus BAC 1-11 200 Series and BAC 1-11 400 Series
- Effective: July 29, 1971
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Amendment: 39-1249
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/C8809BF3203D165D862569A4006643CD.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/71-16-05

## The airworthiness directive

71-16-05 BRITISH AIRCRAFT CORPORATION: Amdt. 39-1249. Applies to Model BAC 1- 11 200 and 400 series airplanes.

To prevent a hazardous drift in the Voltage Sensing Unit, within the next 800 hours' time in service after the effective date of this AD, incorporate Rotax Modification SP 7174 by replacing the transistor T.1 in the Rotax Voltage Sensing Unit Type U.3619 or U.3619/1 with a new transistor, P/N.197235/1, in accordance with Rotax Service Bulletin No. 24-368 dated May 4, 1970, or later ARB-approved issue or an FAA-approved equivalent.

(British Aircraft Corporation Model BAC 1-11 Service Bulletin 24-PM 4641, Revision 2, dated June 15, 1970, refers to this subject.)

This amendment becomes effective July 29, 1971.

## 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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