# AD 47-49-11: Fuel System Inspection

- Type: Airworthiness directive
- Status: Current
- Products: Lockheed 49-46, 649-79 and 749-79
- Superseded by: Nothing supersedes this AD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/25D4F877542B321F8625696D0071A24D.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/47-49-11

## The airworthiness directive

47-49-11 LOCKHEED: (Was Service Note 11 of AD-763-3.) Applies to Models 49, 649, and 749 Serials as Noted.

At periods not to exceed 50 hours of operation, inspect the following fuel system elements to determine that they are tight and will not permit leakage or other hazardous conditions:

  (a) Fuel dump valve shaft gland nuts (Serials up to and including 2075).

  (b) Valves on drain lines from outboard portion of inboard fuel tanks, fuel system crossfeed lines, and cabin heater fuel lines (Serials 2047 to 2088, inclusive, and 2501 to 2503, inclusive).

If safety wiring of these items is provided, the required inspections may be discontinued.

(Lockheed Service Bulletin 49/SB-215 covers part (a), and Lockheed Service Instruction 49/SI-10A covers part (b).)

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS A-763](https://openairdocs.org/tcds/A-763): Lockheed Martin Aeronautics Company; names 3 of 6 models: 649-79, 749-79, 49-46

## 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 49-46](https://openairdocs.org/model/lockheed-49-46): 1 aircraft (airframe model)
- [Lockheed 749-79](https://openairdocs.org/model/lockheed-749-79): 1 aircraft (airframe model)

All 2 models: https://openairdocs.org/ad/47-49-11/models.md
Every aircraft: https://openairdocs.org/ad/47-49-11/aircraft.md

Its text cites no advisory circulars or STCs.

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