# AD 61-03-04: Fuel Vent System

- Type: Airworthiness directive
- Status: Current
- Products: Lockheed Martin Aeronautics 1649A-98
- Effective: February 13, 1961
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Registered aircraft: 1 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/06F0C1146A773E89862569B200718202.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/61-03-04

## The airworthiness directive

61-03-04 LOCKHEED: Amdt. 244 Part 507 Federal Register January 27, 1961. Applies to All Model 1649A Aircraft.

Compliance required as indicated.

One of the following modifications to the vent system must be accomplished within 400 hours of time in service after the effective date of this directive.

  (a) Modify only the right-hand vent float valve of the No. 7 tank (LAC P/N 634024- 3, Aero Supply Mfg. Co. P/N 22-1845-002) to a combination pressure relief and suction relief valve by removing the float assembly so that only the pressure and suction relief features remain operational. Replace the valve spring (P/N 22-0228-1) with spring (P/N 22-0337-1) having a higher cracking pressure.

  (b) Replace only the original right-hand side valve assembly on No. 7 fuel tank with a new valve assembly LAC P/N 634024-5 (Aero Supply Mfg. Co. P/N 22-1845-003).

(Lockheed Letter dated August 22, 1960, directed to all 1649 operators completely covers the details of this modification.)This directive effective February 13, 1961.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS 4A17](https://openairdocs.org/tcds/4A17): Lockheed Martin Aeronautics Company; names 1 of 1 models: 1649A-98

## 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: 1 (1 by airframe model, 0 by engine model)
- Makers: Lockheed 1

Models with the most aircraft:

- [Lockheed 1649A-98](https://openairdocs.org/model/lockheed-1649a-98): 1 aircraft (airframe model)

All 1 models: https://openairdocs.org/ad/61-03-04/models.md
Every aircraft: https://openairdocs.org/ad/61-03-04/aircraft.md

Its text cites no advisory circulars or STCs.

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