# AD 90-02-03: Flap Track

- Type: Airworthiness directive
- Status: Current
- Products: Bombardier DHC-8-101, DHC-8-102, DHC-8-103, DHC-8-106, DHC-8-201, DHC-8-202, DHC-8-301, DHC-8-311, DHC-8-315, DHC-8-400, DHC-8-401 and DHC-8-402
- Effective: February 9, 1990
- Published: January 8, 1990
- Issued: December 18, 1989
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Amendment: 39-6438
- Docket: 89-NM-178
- Registered aircraft: 94 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/06C822CBB537FDC886256A1F007285CF.0001
- DRS record last changed: November 21, 2025
- Page: https://openairdocs.org/ad/90-02-03

## The airworthiness directive

90-02-03 BOEING OF CANADA, LTD., DE HAVILLAND DIVISION: Amendment 39-6438. Docket No. 89-NM-178-AD. Applicability: Model DHC-8 series airplanes, Serial Numbers 1 through 119, certificated in any category.

Compliance: Required within 500 hours time-in-service or 90 days after the effective date of this AD, whichever occurs first, unless previously accomplished.

To prevent fatigue failure of the flap track No. 5 fail safe straps, accomplish the following:

A. Perform a visual inspection for cracks in the flap track No. 5 fail safe straps, in accordance with de Havilland Service Bulletin No. 8-57-10, dated March 31, 1989. If no cracks are found, modify strap holes in accordance with the service bulletin. If cracks are found, replace prior to further flight with a new fail safe strap, in accordance with the service bulletin.

B. An alternate means of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, New York Aircraft Certification Office, ANE-170, FAA, New England Region.

NOTE: The request should be forwarded through an FAA Principal Maintenance Inspector (PMI), who will either concur or comment and then send it to the Manager, New York Aircraft Certification Office, ANE-170.

C. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base in order to comply with the requirements of this AD.

All persons affected by this directive who have not already received the appropriate service documents from the manufacturer may obtain copies upon request to Boeing of Canada, Ltd., de Havilland Division, Garratt Boulevard, Downsview, Ontario M3K 1Y5, Canada. These documents may be examined at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 17900 Pacific Highway South, Seattle, Washington, or at the FAA, New England Region, New York Aircraft Certification Office, 181 South Franklin Avenue, Room 202, Valley Stream, New York.

This amendment (39-6438, AD 90-02-03) becomes effective on February 9, 1990.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS A13NM](https://openairdocs.org/tcds/A13NM): De Havilland Aircraft of Canada Limited; names 12 of 16 models: DHC-8-101, DHC-8-102, DHC-8-103, DHC-8-106, DHC-8-201, DHC-8-202, DHC-8-301, DHC-8-311…

## 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: 94 (94 by airframe model, 0 by engine model)
- Makers: Bombardier 57, Dehavilland 28, Boeing Of Canada/Dehav Div 6, Boeing 3

Models with the most aircraft:

- [Bombardier DHC-8-402](https://openairdocs.org/model/bombardier-dhc-8-402): 26 aircraft (airframe model)
- [Dehavilland DHC-8-202](https://openairdocs.org/model/dehavilland-dhc-8-202): 17 aircraft (airframe model)
- [Bombardier DHC-8-315](https://openairdocs.org/model/bombardier-dhc-8-315): 15 aircraft (airframe model)
- [Bombardier DHC-8-202](https://openairdocs.org/model/bombardier-dhc-8-202): 14 aircraft (airframe model)
- [Dehavilland DHC-8-106](https://openairdocs.org/model/dehavilland-dhc-8-106): 4 aircraft (airframe model)
- [Boeing DHC-8-102](https://openairdocs.org/model/boeing-dhc-8-102): 3 aircraft (airframe model)
- [Boeing Of Canada/Dehav Div DHC-8-311](https://openairdocs.org/model/boeing-of-canada-dehav-div-dhc-8-311): 3 aircraft (airframe model)
- [Boeing Of Canada/Dehav Div DHC-8-106](https://openairdocs.org/model/boeing-of-canada-dehav-div-dhc-8-106): 2 aircraft (airframe model)
- [Bombardier DHC-8-201](https://openairdocs.org/model/bombardier-dhc-8-201): 2 aircraft (airframe model)
- [Dehavilland DHC-8-201](https://openairdocs.org/model/dehavilland-dhc-8-201): 2 aircraft (airframe model)
- [Dehavilland DHC-8-103](https://openairdocs.org/model/dehavilland-dhc-8-103): 2 aircraft (airframe model)
- [Dehavilland DHC-8-315](https://openairdocs.org/model/dehavilland-dhc-8-315): 2 aircraft (airframe model)
- [Boeing Of Canada/Dehav Div DHC-8-102](https://openairdocs.org/model/boeing-of-canada-dehav-div-dhc-8-102): 1 aircraft (airframe model)
- [Dehavilland DHC-8-102](https://openairdocs.org/model/dehavilland-dhc-8-102): 1 aircraft (airframe model)

All 14 models: https://openairdocs.org/ad/90-02-03/models.md
Every aircraft: https://openairdocs.org/ad/90-02-03/aircraft.md

Its text cites no advisory circulars or STCs.

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