AD 90-25-16

final rule
Data completeness: 70%

Airworthiness Directives; Boeing Of Canada, Ltd., De Havilland Division Model DHC-7 Series Airplanes

AD Number
90-25-16
Status
final_rule
Effective Date
Product Category
aircraft
Docket
90-NM-147-AD
FR Citation
This information is not available.

Applicability

TypeManufacturerModelDetails
aircraft Viking Air Limited DHC-7-1 Airworthiness Directives; Boeing Of Canada, Ltd., De Havilland Division Model DHC-7 Series Airplanes
aircraft Viking Air Limited DHC-7-100 Airworthiness Directives; Boeing Of Canada, Ltd., De Havilland Division Model DHC-7 Series Airplanes
aircraft Viking Air Limited DHC-7-101 Airworthiness Directives; Boeing Of Canada, Ltd., De Havilland Division Model DHC-7 Series Airplanes
aircraft Viking Air Limited DHC-7-102 Airworthiness Directives; Boeing Of Canada, Ltd., De Havilland Division Model DHC-7 Series Airplanes
aircraft Viking Air Limited DHC-7-103 Airworthiness Directives; Boeing Of Canada, Ltd., De Havilland Division Model DHC-7 Series Airplanes

Unsafe Condition

Possible malfunction of the right main landing gear (MLG) due to undetected damage to the frame and attachment bolts.

AI-generated summary from the source AD text. Verify against the official source before acting.

Required Actions

Within 100 landings after May 29, 1990, and every 500 landings thereafter, conduct a visual inspection of the right MLG frame and bolts per Service Bulletin 7-24-66 Rev B. If damage is found, replace parts before further flight. Install Modification 7/2577 within 180 days after January 14, 1991, to relocate the external power grounding stud.

AI-generated summary from the source AD text. Verify against the official source before acting.

Compliance Time

Within 100 landings after May 29, 1990 (for inspections) and within 180 days after January 14, 1991 (for modification installation).

AI-generated summary from the source AD text. Verify against the official source before acting.

Affected Aircraft

Boeing Of Canada, Ltd., De Havilland Division Model DHC-7 series airplanes, certificated in any category.

AI-generated summary from the source AD text. Verify against the official source before acting.

Source: Official FAA Source ↗

Retrieved: Apr 8, 2026

Rights: U.S. Government Public Domain

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