# AD 56-18-02: Crankcase

- Type: Airworthiness directive
- Status: Current
- Products: Kelowna Flightcraft R & D 340
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Registered aircraft: 7 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/23833338FE7D4A31862569AB006EDCA4.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/56-18-02

## The airworthiness directive

56-18-02 CONVAIR: Applies to All 340 Aircraft.

Compliance required preferably at next engine overhaul but not later than June 1, 1957.

Due to the possibility in hot weather operation that the engines installed in Convair 340 airplanes can experience excessive oil temperatures and inability to scavenge the crankcase, Pratt & Whitney Aircraft Service Bulletins Nos. 1513 and 1524 shall be accomplished as indicated above.

This serious condition, which has been experienced in hot weather on several occasions by two scheduled airline operators, is attributed mainly to high oil flow rates, which will be effectively reduced by compliance with these Pratt & Whitney Service Bulletins.

(Air Carrier Maintenance Alert Bulletin No. 241 also deals with this subject.)

As an alternate to compliance with these bulletins, the adoption of maintenance practices and engine overhaul procedures which effectively reduce oil flow rates will be acceptable.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS 6A6](https://openairdocs.org/tcds/6A6): Kelowna Flightcraft R & D Ltd.; names 1 of 6 models: 340

## 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: 7 (7 by airframe model, 0 by engine model)
- Makers: Convair 7

Models with the most aircraft:

- [Convair 340](https://openairdocs.org/model/convair-340): 7 aircraft (airframe model)

All 1 models: https://openairdocs.org/ad/56-18-02/models.md
Every aircraft: https://openairdocs.org/ad/56-18-02/aircraft.md

Its text cites no advisory circulars or STCs.

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