# AD 52-08-01: Fuel Tank Seal

- Type: Airworthiness directive
- Status: Current
- Products: Lockheed 18
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Registered aircraft: 2 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/B2C13E4756FE1D7B8625696D0071A8AB.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/52-08-01

## The airworthiness directive

52-08-01 LOCKHEED: Applies to Certificated Army and Navy Versions of the Model 18 Aircraft Designated C57, C57B, R50-1, R50-2, R50-3, R50-5, R50-6, C60, C60A and C59.

Compliance required at next annual inspection, but in no event later than June 1, 1953.

Inspect all Lockheed Model 18 Series aircraft which have been converted from a military version to civil status, for compliance with Lockheed Drawing No. 50829, change A, to provide seal at the inboard end of the integral fuel tanks (inside fuselage) to prevent gasoline fumes from accumulating in the passenger compartment in case of fuel tank leakage. Inspection of the area can be accomplished by removal of the overhead panels adjacent to the fuselage skin in the No. 3 and No. 4 baggage compartments or by removing floor panels in the cabin.

Diaphragms and vents must be installed in accordance with Lockheed Drawing No. 50829 (or equivalent).

(Drawing No. 50829, change A, covering the required installation may be obtained from Lockheed Aircraft Corp., Burbank, Calif.)

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS A-723](https://openairdocs.org/tcds/A-723): Lockheed Martin Aeronautics Company; names 1 of 1 models: 18

## 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: 2 (2 by airframe model, 0 by engine model)
- Makers: Lockheed 2

Models with the most aircraft:

- [Lockheed 18](https://openairdocs.org/model/lockheed-18): 2 aircraft (airframe model)

All 1 models: https://openairdocs.org/ad/52-08-01/models.md
Every aircraft: https://openairdocs.org/ad/52-08-01/aircraft.md

Its text cites no advisory circulars or STCs.

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