# AD 47-10-26: Flap drain Line Rerouting

- Type: Airworthiness directive
- Status: Current
- Products: Lockheed 49-46
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Registered aircraft: 1 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/9B3CD0C22DAB66CD8625696D00458CE3.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/47-10-26

## The airworthiness directive

47-10-26 LOCKHEED: (Was Mandatory Note 29 of AD-763-3.) Applies to All Model 49 Serials Up to and Including 2075.

Compliance required prior to June 1, 1947.

Reroute flap and fan motor drain lines to return direct to main hydraulic system instead of through aspirator, and install check valves at points where drain lines connect to the main system.

(LAC Service Bulletin 49/SB-169 covers this same subject.)

## 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 1 of 6 models: 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: 1 (1 by airframe model, 0 by engine model)
- Makers: Lockheed 1

Models with the most aircraft:

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

All 1 models: https://openairdocs.org/ad/47-10-26/models.md
Every aircraft: https://openairdocs.org/ad/47-10-26/aircraft.md

Its text cites no advisory circulars or STCs.

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