# AD 50-06-01: Ventral Fin Replacement

- Type: Airworthiness directive
- Status: Current
- Products: Scotts-Bell 47 47D1
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Rotorcraft
- Registered aircraft: 49 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/95222B578BA62C5486256A34004E74A3.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/50-06-01

## The airworthiness directive

50-06-01 BELL: Applies to All Model 47D1 Helicopters.

Compliance required not later than March 31, 1950.

Ventral fin installation, Bell P/N 47-267-058 should be replaced by the revised ventral fin and fixed tab installation, Bell P/N 47-267-063. The new installation is designed to eliminate the possibility of those fatigue failures which have been experienced in the old design.

Upon completion of the above modifications, the inspections required by AD 49-34-02 may be discontinued.

(Bell Service Bulletin No. 71 covers the same subject.)

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS H-1](https://openairdocs.org/tcds/H-1): Scott's-Bell 47 Inc; names 1 of 9 models: 47D1

## 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: 49 (49 by airframe model, 0 by engine model)
- Makers: Bell 47, Bell Kitz Kopters 1, Bell-Allied Helicopter 1

Models with the most aircraft:

- [Bell 47D1](https://openairdocs.org/model/bell-47d1): 47 aircraft (airframe model)
- [Bell Kitz Kopters 47D1](https://openairdocs.org/model/bell-kitz-kopters-47d1): 1 aircraft (airframe model)
- [Bell-Allied Helicopter 47D1](https://openairdocs.org/model/bell-allied-helicopter-47d1): 1 aircraft (airframe model)

All 3 models: https://openairdocs.org/ad/50-06-01/models.md
Every aircraft: https://openairdocs.org/ad/50-06-01/aircraft.md

Its text cites no advisory circulars or STCs.

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