# AD 64-22-01: Fuel Tank Vent Float Valve Arms

- 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: October 22, 1964
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Registered aircraft: 6 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/0B05F6DBF296F0828625699200521EFC.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/64-22-01

## The airworthiness directive

64-22-01 BOEING: Amdt. 815 Part 507 Federal Register September 19, 1964. Applies to Models 707 and 720 Series Aircraft.

Compliance required as indicated.

There have been failures of the fuel tank vent float valve arms causing the float to break loose from the main valve assembly. This permits the vent valve (which is normally float actuated to the closed position by a high fuel level) to remain open and allow (under some flight conditions) fuel to fill the surge tank and spill out the wing tip vent scoop. To correct this condition, accomplish the following:

  (a) Within 500 hours' time in service after the effective date of this directive, unless already accomplished in the previous 500 hours' time in service and within every 1,000 hours time in service thereafter until compliance with (b) has been accomplished, visually inspect the reserve fuel tank vent valve assemblies in each wing for cracks or deformation. If the valve assembly is in a failed condition, or if cracks or deformed parts are found, replace the parts before further flight.

  (b) Within 6,000 hours' time in service after the effective date of this directive modify all fuel tank vent valve assemblies in each tank by installing a float stop bracket assembly, Boeing P/N 69-31399-1, in accordance with Boeing Service Bulletin No. 1958 or an equivalent method processed through the Aircraft Engineering Division, FAA Western Region, Los Angeles, California. When this modification has been accomplished the repetitive inspection of (a) may be discontinued.

  (c) Upon request of the operator, an FAA maintenance inspector, subject to prior approval of the Chief, Aircraft Engineering Division, FAA Western 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 such operator.

(Boeing Service Bulletin No. 1958 covers thissubject.)

This directive effective October 22, 1964.

## 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/64-22-01/models.md
Every aircraft: https://openairdocs.org/ad/64-22-01/aircraft.md

Its text cites no advisory circulars or STCs.

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