# AD 47-42-12: Astrodrome Reinforcement

- Type: Airworthiness directive
- Status: Current
- Products: Boeing DC-6, DC-6A and DC-6B
- Superseded by: Nothing supersedes this AD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/9366C8FEB0A20AC8862569BC0049CCC5.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/47-42-12

## The airworthiness directive

47-42-12 DOUGLAS: (Was Mandatory Note 9 of AD-781-1.) Applies to DC-6 Serial Numbers 42866, and 42868 to 42875, Inclusive.

To be accomplished not later than February 1, 1948.

In order to provide adequate fastening of the rubber cushions on the reinforcing strap assembly of the astrodome, the following must be accomplished:

1. Remove the existing rubber strap cushions, P/N 5249604-36, all traces of cement and adhering rubber from reinforcing strap assembly, P/N 5249604-38.

2. Butt cushion assembly P/N 2356419 against pad P/N 5249604-42, locate and drill four No. 40 (0.098) holes through strap P/N 5249604-38 and attach with AN 426-AD-3-5 rivets.

3. Reinstall reinforcing strap assembly P/N 5249604-38, using eight AN 960-D-10L washers and eight AN 365-1032 nuts.

(Douglas Service Bulletin DC-6 No. 45 covers this same subject.)

## Affected data sheets (3) (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

## 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/47-42-12/models.md
Every aircraft: https://openairdocs.org/ad/47-42-12/aircraft.md

Its text cites no advisory circulars or STCs.

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