# AD 71-11-01: Protection for Circuit Wires

- Type: Airworthiness directive
- Status: Current
- Products: Viking Air DHC-6-1, DHC-6-100, DHC-6-200 and DHC-6-300
- Effective: May 19, 1971
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Small airplane
- Amendment: 39-1212
- Registered aircraft: 88 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/740F509F7B7B182C86256A34006EC01D.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/71-11-01

## The airworthiness directive

71-11-01 De HAVILLAND AIRCRAFT OF CANADA, LIMITED: Amdt. 39-1212. Applies to de Havilland Model DHC-6 Airplanes certificated in all categories.

Compliance required within the next 500 hours time in service after the effective date of this AD unless already accomplished.

To provide adequate protection for particular circuit wires, accomplish the following in accordance with the instructions contained in DHC Service Bulletin No. 6/245 dated October 9, 1970:

  (a) Alter airplanes, S/Ns 6 through 289, except S/Ns 176, 221, 233, 268 and 286, by incorporating DHC Modification No. 6/1369;

  (b) Alter airplanes, S/Ns 1 through 289, except S/Ns 176, 233, 268, and 286, by incorporating DHC Modification No. 6/1370;

  (c) Alter airplanes, S/Ns 6 through 289, except S/Ns 176, 221, 233, 268 and 286, by incorporating DHC Modification No. 6/1371. Modification No. 6/1371 is applicable only to those airplanes in which DHC Modification No. 6/1053 has been incorporated;

  (d) Alter airplanes, S/Ns 136 through 289, except S/Ns 176, 221, 233, 268, and 286, by incorporating DHC Modification No. 6/1372;

  (e) Alter airplanes, S/Ns 136 through 289, by incorporating DHC Modification No. 6/1389.

Equivalent alterations may be used provided they are approved by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region.

Upon request with substantiation data submitted through an FAA maintenance inspector, the compliance time specified in this AD may be increased by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region.

This amendment is effective May 19, 1971.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS A9EA](https://openairdocs.org/tcds/A9EA): De Havilland Aircraft of Canada Limited; names 4 of 5 models: DHC-6-1, DHC-6-100, DHC-6-200, DHC-6-300

## 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: 88 (88 by airframe model, 0 by engine model)
- Makers: Dehavilland 84, Dehavilland Acft Of Canada 4

Models with the most aircraft:

- [Dehavilland DHC-6-300](https://openairdocs.org/model/dehavilland-dhc-6-300): 59 aircraft (airframe model)
- [Dehavilland DHC-6-200](https://openairdocs.org/model/dehavilland-dhc-6-200): 19 aircraft (airframe model)
- [Dehavilland DHC-6-100](https://openairdocs.org/model/dehavilland-dhc-6-100): 6 aircraft (airframe model)
- [Dehavilland Acft Of Canada DHC 6-300](https://openairdocs.org/model/dehavilland-acft-of-canada-dhc-6-300): 4 aircraft (airframe model)

All 4 models: https://openairdocs.org/ad/71-11-01/models.md
Every aircraft: https://openairdocs.org/ad/71-11-01/aircraft.md

Its text cites no advisory circulars or STCs.

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