# AD 81-13-01: Elevator Butt Ribs

- Type: Airworthiness directive
- Status: Current
- Products: Viking Air DHC-2 Mk.I, DHC-2 Mk.II and DHC-2 Mk.III
- Effective: June 18, 1981
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Small airplane
- Amendment: 39-4134
- Registered aircraft: 140 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/77C5E9489FFBC89786256A4E00581D45.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/81-13-01

## The airworthiness directive

81-13-01 DEHAVILLAND: Amendment 39-4134. Applies to all DeHavilland DHC-2 series airplanes, certificated in all categories.

Compliance required as indicated.

Affects the elevator butt ribs (inboard), P/N C2TE-29ND (RH and LH), and doublers, P/N C2TE-9ND (RH and LH).

a. Within the next 75 hours in service after the effective date of this AD, unless already accomplished within the last 325 hours in service, and thereafter at intervals not to exceed 400 hours in service from the last inspection, inspect visually with a 10-power glass, the left and right elevator butt ribs and doublers for cracks.

b. Replace or repair cracked parts, before further flight, in accordance with DeHavilland Service Bulletin (S/B) No. 2/30, or equivalent.

c. Equivalent parts or repairs must be approved by the Chief, Engineering and Manufacturing Branch, FAA, Eastern Region.

d. Upon submission of substantiating data by an owner or operator, through an FAA maintenance inspector,the Chief, Engineering and Manufacturing Branch, FAA, Eastern Region, may adjust the compliance times specified in this AD.

This amendment becomes effective June 18, 1981.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS A-806](https://openairdocs.org/tcds/A-806): De Havilland Aircraft of Canada Limited; names 3 of 3 models: DHC-2 Mk.II, DHC-2 Mk.III, DHC-2 Mk.I

## 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: 140 (140 by airframe model, 0 by engine model)
- Makers: Dehavilland 135, Dehavilland Acft Of Canada 3, Dehavilland-Shawano 2

Models with the most aircraft:

- [Dehavilland DHC-2 MK. I(L20A)](https://openairdocs.org/model/dehavilland-dhc-2-mk-i-l20a): 91 aircraft (airframe model)
- [Dehavilland DHC 2 MK III](https://openairdocs.org/model/dehavilland-dhc-2-mk-iii): 24 aircraft (airframe model)
- [Dehavilland DHC-2 MK.I](https://openairdocs.org/model/dehavilland-dhc-2-mk-i): 20 aircraft (airframe model)
- [Dehavilland Acft Of Canada DHC-2 MK I](https://openairdocs.org/model/dehavilland-acft-of-canada-dhc-2-mk-i): 3 aircraft (airframe model)
- [Dehavilland-Shawano DHC-2 MK.I](https://openairdocs.org/model/dehavilland-shawano-dhc-2-mk-i): 2 aircraft (airframe model)

All 5 models: https://openairdocs.org/ad/81-13-01/models.md
Every aircraft: https://openairdocs.org/ad/81-13-01/aircraft.md

Its text cites no advisory circulars or STCs.

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