# AD 71-09-01: Nacelle Electrical Failures

- Type: Airworthiness directive
- Status: Current
- Products: Cessna 320, 320-1, 320A, 320B, 320C, 320D, 320E and 320F
- Effective: April 23, 1971
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Small airplane
- Amendment: 39-1193
- Registered aircraft: 137 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/C369646A0497D05686256A340062D6A7.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/71-09-01

## The airworthiness directive

71-09-01 CESSNA: Amdt. 39-1193. Applies to all Model 320 series Airplanes.

Compliance: Required as indicated, unless already accomplished.

To prevent nacelle electrical failures and inflight electrical fires, accomplish the following:

A) Within the next 50 hours' time in service after the effective date of this AD, and thereafter at intervals not to exceed 100 hours' time in service from the date of the last inspection, visually inspect the following:

1) The insulating material of the electrical wiring, grommet and clamps located in the engine nacelles between the canted bulkhead and the firewall for charred, burnt or heat hardened conditions;

2) The heat shields located in the engine nacelles between the canted bulkhead and the forewall for deterioration or improper installation and attachment that could contribute to excessive heat in this area.

B) If any of the conditions described in Paragraph A are found during the required inspections, prior tofurther flight, except that the airplane may be flown in accordance with FAR 21.197 to a base where the replacement can be performed, replace any defective parts with airworthy parts. The replacement of defective parts does not relieve the requirement for the repeated inspections specified in Paragraph A.

C) Upon request of the operator, an FAA maintenance inspector, subject to prior approval of the Chief, Engineering and Manufacturing Branch, FAA, Central Region, may adjust the repetitive inspection intervals specified in this AD to permit compliance at an established inspection period of the operator if the request contains substantiating data to justify the increase for that operator.

D) On or before January 1, 1972 modify the engine nacelles in accordance with Cessna Service Letter ME71-6, dated April 9, 1971, and Cessna Service Kit SK320-53, dated March 5, 1971, or any other method approved by the Chief, Engineering and Manufacturing Branch, FAA, Central Region.

E) When the engine nacelles are modified in accordance with Cessna Service Letter ME71-6, dated April 9, 1971, and Cessna Service Kit SK320-53, dated March 5, 1971, the inspections required by Paragraph A will no longer be required.

This amendment becomes effective April 23, 1971.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS 3A25](https://openairdocs.org/tcds/3A25): Textron Aviation Inc.; names 8 of 11 models: 320, 320D, 320-1, 320B, 320E, 320C, 320F, 320A

## 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: 137 (137 by airframe model, 0 by engine model)
- Makers: Cessna 137

Models with the most aircraft:

- [Cessna 320D](https://openairdocs.org/model/cessna-320d): 30 aircraft (airframe model)
- [Cessna 320E](https://openairdocs.org/model/cessna-320e): 27 aircraft (airframe model)
- [Cessna 320C](https://openairdocs.org/model/cessna-320c): 23 aircraft (airframe model)
- [Cessna 320B](https://openairdocs.org/model/cessna-320b): 21 aircraft (airframe model)
- [Cessna 320](https://openairdocs.org/model/cessna-320): 17 aircraft (airframe model)
- [Cessna 320F](https://openairdocs.org/model/cessna-320f): 12 aircraft (airframe model)
- [Cessna 320A](https://openairdocs.org/model/cessna-320a): 6 aircraft (airframe model)
- [Cessna 320-1](https://openairdocs.org/model/cessna-320-1): 1 aircraft (airframe model)

All 8 models: https://openairdocs.org/ad/71-09-01/models.md
Every aircraft: https://openairdocs.org/ad/71-09-01/aircraft.md

Its text cites no advisory circulars or STCs.

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