# AD 65-07-01: Return Air System

- Type: Airworthiness directive
- Status: Current
- Products: Boeing 707-100 Long Body, 707-100B Long Body, 707-100B Short Body, 707-200, 707-300 Series, 707-300B Series, 707-300C Series, 707-400 Series, 720 Series and 720B Series
- Effective: April 1, 1965
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Amendment: 39-51
- Registered aircraft: 6 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/799ACF8B2309B6918625682E00542E46.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/65-07-01

## The airworthiness directive

65-07-01 BOEING: Amdt. 39-51 Part 39 Federal Register April 1, 1965. Applies to Models 707 and 720 Series Aircraft.

Compliance required as indicated.

To reduce the possibility of further fires in the cabin lower sidewall panels in the return air system, accomplish the following:

  (a) Within 5,000 hours' time in service after March 20, 1964, install lower sidewall modifications, including flame-resistant insulation, fire-stop air baffles, and metal grills, in areas other than behind galleys and other equipment located flush against the cabin sidewall, in accordance with Boeing Service Bulletins Nos. 1807(R-1), 1807(R-1)A, 1861, and 1868, as applicable, or an FAA-approved equivalent.

  (b) Within 6,000 hours' time in service after March 20, 1964, install lower sidewall modifications, including flame-resistant insulation, fire-stop air baffles, and metal grills, behind galleys and other equipment located flush against the cabin sidewall in accordance with Boeing Service Bulletins Nos. 1807(R-1), 1807(R-1)A, 1861, and 1868, as applicable, or an FAA- approved equivalent.

This supersedes AD 64-04-01.

This directive effective April 1, 1965.

## Affected data sheets (3) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS 4A21](https://openairdocs.org/tcds/4A21): The Boeing Company; names 4 of 4 models: 707-100B Short Body, 707-200, 707-100 Long Body, 707-100B Long Body
- [TCDS 4A26](https://openairdocs.org/tcds/4A26): The Boeing Company; names 4 of 4 models: 707-300B Series, 707-400 Series, 707-300 Series, 707-300C Series
- [TCDS 4A28](https://openairdocs.org/tcds/4A28): The Boeing Company; names 2 of 2 models: 720B Series, 720 Series

## 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: 6 (6 by airframe model, 0 by engine model)
- Makers: Boeing 6

Models with the most aircraft:

- [Boeing 707-338C](https://openairdocs.org/model/boeing-707-338c): 2 aircraft (airframe model)
- [Boeing 707-368C](https://openairdocs.org/model/boeing-707-368c): 1 aircraft (airframe model)
- [Boeing 707-321B](https://openairdocs.org/model/boeing-707-321b): 1 aircraft (airframe model)
- [Boeing 707-323B](https://openairdocs.org/model/boeing-707-323b): 1 aircraft (airframe model)
- [Boeing 707-351B](https://openairdocs.org/model/boeing-707-351b): 1 aircraft (airframe model)

All 5 models: https://openairdocs.org/ad/65-07-01/models.md
Every aircraft: https://openairdocs.org/ad/65-07-01/aircraft.md

Its text cites no advisory circulars or STCs.

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