# AD 47-10-23: Bathtub Fitting Steel Nuts

- 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- Superseded by: Nothing supersedes this AD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/252DE3396406BE338625696D00458BBF.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/47-10-23

## The airworthiness directive

47-10-23 LOCKHEED: (Was Mandatory Note 25 of AD-763-3.) Applies to Model 49 Serials 1975, 1976, and 2021 Through 2059.

Compliance required immediately.

Install AC364-524 steel nuts in place of any AC364-B524 brass nuts which may be installed on bolts through bathtub fittings at wing Station 80 (5 nuts per fitting, 170 nuts per airplane should be checked.

(LAC Service Bulletin 49/SB-42 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/47-10-23/models.md
Every aircraft: https://openairdocs.org/ad/47-10-23/aircraft.md

Its text cites no advisory circulars or STCs.

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