# AD 47-33-04: Fuel Leakage

- Type: Airworthiness directive
- Status: Current
- Products: Textron C18S
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Small airplane
- Registered aircraft: 13 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/8F591025E75ACAC286256A1C00720EBF.0001
- DRS record last changed: January 21, 2026
- Page: https://openairdocs.org/ad/47-33-04

## The airworthiness directive

47-33-04 BEECH: (Was Service Note 2 of AD-757-2.) Applies to C18S Aircraft.

Compliance required prior to October 15, 1947, and each 100 hours of operation thereafter.

Inspect gaskets between fuel tank liquidometer units and tanks for fuel leakage. If leakage is evident, replace gasket with Armstrong No. 710 gasket, Beech P/N 189631, without use of sealing compound. (Installation of 189631 gasket eliminates necessity for continued inspections.)

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS A-757](https://openairdocs.org/tcds/A-757): Textron Aviation Inc.; names 1 of 1 models: C18S

## 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: 13 (13 by airframe model, 0 by engine model)
- Makers: Beech 13

Models with the most aircraft:

- [Beech C18S](https://openairdocs.org/model/beech-c18s): 13 aircraft (airframe model)

All 1 models: https://openairdocs.org/ad/47-33-04/models.md
Every aircraft: https://openairdocs.org/ad/47-33-04/aircraft.md

Its text cites no advisory circulars or STCs.

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