# AD 47-27-02: Spar Web Structure

- Type: Airworthiness directive
- Status: Current
- Products: Boeing C54-DC, C54A-DC, C54B-DC, C54D-DC, C54E-DC, C54G-DC and DC-4
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Registered aircraft: 4 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/EB1AF2974ED619E586256CC4006A86F7.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/47-27-02

## The airworthiness directive

47-27-02 DOUGLAS: (Was Service Note 4 of AD-762-7.) Applies to All C-54-DC Series and DC-4 Airplanes.

Inspection required at intervals not to exceed 170 hours.

Open the quick-opening type inspection doors in the bottom of the outer wing and center wing section surfaces forward of the front spar and aft of the center spar. Inspect spar web structure for loose rivets, cracks, or other irregularities. Pay particular attention in the fuel tank areas for evidence of fuel leaks which will indicate cracked spar webs or rivets and seam leaks.

All spar web cracks which are found after accomplishment of AD 46-27-01 (Service Bulletin C-54-205. "Rework - Integral Fuel Tanks") or cracks that are located in areas to which the Service Bulletin C-54-205 does not apply, should be repaired in accordance with Douglas Drawing No. 5354811, "Service Rework-Station 463, Outer Wing, Center Spar", and No. 3344236, "Repair-Integral Tank Spar Web Crack".

Revised March 21, 1961.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS A-762](https://openairdocs.org/tcds/A-762): The Boeing Company; names 7 of 7 models: C54E-DC, C54G-DC, C54B-DC, DC-4, C54A-DC, C54D-DC, C54-DC

## 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: 4 (4 by airframe model, 0 by engine model)
- Makers: Douglas 4

Models with the most aircraft:

- [Douglas C54D-DC](https://openairdocs.org/model/douglas-c54d-dc): 2 aircraft (airframe model)
- [Douglas C54E-DC](https://openairdocs.org/model/douglas-c54e-dc): 1 aircraft (airframe model)
- [Douglas C54G-DC](https://openairdocs.org/model/douglas-c54g-dc): 1 aircraft (airframe model)

All 3 models: https://openairdocs.org/ad/47-27-02/models.md
Every aircraft: https://openairdocs.org/ad/47-27-02/aircraft.md

Its text cites no advisory circulars or STCs.

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