# AD 47-42-19: Horizontal Stabilizer Front Spar Cap

- 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- Superseded by: Nothing supersedes this AD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/EFEACA7EEC63E151862569BC004B4CC2.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/47-42-19

## The airworthiness directive

47-42-19 DOUGLAS: (Was Service Note 5 of AD-781-1.) Applies to the Following DC-6 Aircraft: Serial Numbers 42854 to 42894, Inclusive; 43000 to 43012, Inclusive; 43055, 43056, and 43062.

Inspection required at every engine change.

After the stop holes are drilled in the tail stub extension of the horizontal stabilizer front spar caps, as required by AD 47-42-11, inspect for signs of cracks, or progress of cracks, at each engine change period. If the aircraft has been modified to incorporate the elevator fifth hinge modification, the inspection period may be extended to every other engine change period, but not to exceed 3,000 hours of airplane operation. If cracks progress beyond the stop hole, operation of the airplane must be discontinued until additional corrective measures have been determined.

## 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/47-42-19/models.md
Every aircraft: https://openairdocs.org/ad/47-42-19/aircraft.md

Its text cites no advisory circulars or STCs.

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