# AD 49-30-01: Hub Barrels

- Type: Airworthiness directive
- Status: Current
- Products: Boeing DC-6, DC-6A, DC-6B and 240 Series
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Registered aircraft: 17 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/CBAD8B36B8D9478F862569AB006918A4.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/49-30-01

## The airworthiness directive

49-30-01 DOUGLAS AND CONVAIR: Applies to All DC-6 and 240 Aircraft Equipped With Curtiss Model C632S-A Propellers.

Compliance required as soon as possible but not later than August 15, 1949.

Because of a number of cracks having been discovered in the threaded portion of the hub barrels of the C632S-A propellers, preflight visual inspections must be made in accordance with Curtiss Instructions to all owners dated May 12, 1949.

It is strongly recommended that wherever the necessary equipment is available, magnetic inspections be made in accordance with Curtiss Instructions entitled, "Field Magnetic Inspection of C632S-A Hubs".

Any hubs revealing cracks must be retired from service immediately.

The above inspections are to remain in effect as long as these propellers are in service regardless of any rework accomplished.

Operational procedures for the Douglas DC-6 during ground run, takeoff and climb, as recommended by the Douglas Co. telegram of May 25, 1949, must also be complied with.

## Affected data sheets (4) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS 6A3](https://openairdocs.org/tcds/6A3): The Boeing Company; names 1 of 3 models: DC-6A
- [TCDS 6A4](https://openairdocs.org/tcds/6A4): The Boeing Company; names 1 of 2 models: DC-6B
- [TCDS A-781](https://openairdocs.org/tcds/A-781): The Boeing Company; names 1 of 1 models: DC-6
- [TCDS A-793](https://openairdocs.org/tcds/A-793): Kelowna Flightcraft R & D Ltd.; names 1 of 1 models: 240 Series

## 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: 17 (17 by airframe model, 0 by engine model)
- Makers: Douglas 17

Models with the most aircraft:

- [Douglas DC-6B](https://openairdocs.org/model/douglas-dc-6b): 9 aircraft (airframe model)
- [Douglas DC-6A](https://openairdocs.org/model/douglas-dc-6a): 7 aircraft (airframe model)
- [Douglas DC-6](https://openairdocs.org/model/douglas-dc-6): 1 aircraft (airframe model)

All 3 models: https://openairdocs.org/ad/49-30-01/models.md
Every aircraft: https://openairdocs.org/ad/49-30-01/aircraft.md

Its text cites no advisory circulars or STCs.

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