AD 80-26-03
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Viking Air Limited | DHC-4 | Airworthiness Directives; DeHavilland Model DHC-4 and DHC-4A Aircraft |
| aircraft | Viking Air Limited | DHC-4A | Airworthiness Directives; DeHavilland Model DHC-4 and DHC-4A Aircraft |
Unsafe Condition
Failure of the left hand magneto drive mechanism
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Incorporate the right-hand magneto drive and associated parts as described in Pratt & Whitney Aircraft Service Bulletin No. 1756 or approved equivalent instructions and parts. Redesignate the engines as noted in Section C of the service bulletin.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
within the next 1400 hours in service after the effective date of this AD unless already accomplished
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Affected Aircraft
DeHavilland Model DHC-4 and DHC-4A aircraft equipped with Pratt & Whitney Aircraft Twin Wasp D-5 and R-2000-7M2 engines incorporating left-hand magneto drive arrangement
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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