# AD 46-21-01: Landing Gear Universal Joints

- Type: Airworthiness directive
- Status: Current
- Products: Fairchild Industries 24 C8, 24 C8A, 24 C8B, 24 C8D, 24 C8DS, 24 C8E, 24 C8ES, 24 C8F (Army UC-61J), 24 C8FS, 24G (Army UC-61H), 24GS, 24H and 5 more
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Small airplane
- Registered aircraft: 54 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/A9060EABB6C9772A86256A38004EE089.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/46-21-01

## The airworthiness directive

46-21-01 FAIRCHILD: (Was Mandatory Note 6 of AD-702-2: 2 of AD-706-1; 4 of AD- 517-2; 5 of AD-535-2; 4 of AD-564-2; 5 of AD-633-2; 5 of AD-600-2; 4 of AD-667-2.) Applies to Model 24 Series Aircraft.

Compliance required at next periodic inspection.

To correct the freezing of the upper and lower universal joints on the landing gear oleo shock struts, install new universal joints, Fairchild P/N 3330 and 3328.

(Fairchild Service Bulletin 46-24-1-A, revised December 23, 1946, covers this same subject.)

## Affected data sheets (10) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS ATC 576](https://openairdocs.org/tcds/ATC%20576): Fairchild Industries Inc.; names 2 of 2 models: 24 C8D, 24 C8DS
- [TCDS ATC 600](https://openairdocs.org/tcds/ATC%20600): Fairchild Industries Inc.; names 2 of 2 models: 24 C8ES, 24 C8E
- [TCDS ATC 610](https://openairdocs.org/tcds/ATC%20610): Fairchild Industries Inc.; names 2 of 2 models: 24 C8F (Army UC-61J), 24 C8FS
- [TCDS ATC 632](https://openairdocs.org/tcds/ATC%20632): Fairchild Industries Inc.; names 2 of 2 models: 24H, 24HS
- [TCDS ATC 633](https://openairdocs.org/tcds/ATC%20633): Fairchild Industries Inc.; names 2 of 2 models: 24G (Army UC-61H), 24GS
- [TCDS TC 663](https://openairdocs.org/tcds/TC%20663): Fairchild Industries Inc.; names 2 of 2 models: 24JS, 24J (Army UC-61B)
- [TCDS TC 667](https://openairdocs.org/tcds/TC%20667): Fairchild Industries Inc.; names 2 of 2 models: 24KS, 24K (Army UC-61E)
- [TCDS ATC 475](https://openairdocs.org/tcds/ATC%20475): Fairchild Industries Inc.; names 1 of 1 models: 24 C8
- [TCDS ATC 497](https://openairdocs.org/tcds/ATC%20497): Fairchild Industries Inc.; names 1 of 1 models: 24 C8A
- [TCDS ATC 498](https://openairdocs.org/tcds/ATC%20498): Fairchild Industries Inc.; names 1 of 1 models: 24 C8B

## 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: 54 (54 by airframe model, 0 by engine model)
- Makers: Fairchild 54

Models with the most aircraft:

- [Fairchild 24 G](https://openairdocs.org/model/fairchild-24-g): 14 aircraft (airframe model)
- [Fairchild 24 H](https://openairdocs.org/model/fairchild-24-h): 9 aircraft (airframe model)
- [Fairchild 24 J](https://openairdocs.org/model/fairchild-24-j): 8 aircraft (airframe model)
- [Fairchild 24 C8E](https://openairdocs.org/model/fairchild-24-c8e): 6 aircraft (airframe model)
- [Fairchild 24 K](https://openairdocs.org/model/fairchild-24-k): 6 aircraft (airframe model)
- [Fairchild 24 C8F](https://openairdocs.org/model/fairchild-24-c8f): 5 aircraft (airframe model)
- [Fairchild 24 C8A](https://openairdocs.org/model/fairchild-24-c8a): 4 aircraft (airframe model)
- [Fairchild 24 C8](https://openairdocs.org/model/fairchild-24-c8): 1 aircraft (airframe model)
- [Fairchild 24 C8D](https://openairdocs.org/model/fairchild-24-c8d): 1 aircraft (airframe model)

All 9 models: https://openairdocs.org/ad/46-21-01/models.md
Every aircraft: https://openairdocs.org/ad/46-21-01/aircraft.md

Its text cites no advisory circulars or STCs.

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