AD 71-21-07

final rule
Data completeness: 70%

Airworthiness Directives; de Havilland Model DHC- 6 Series Airplanes

AD Number
71-21-07
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Unknown
FR Citation
This information is not available.

Applicability

TypeManufacturerModelDetails
aircraft Viking Air Limited DHC-6-1 Airworthiness Directives; de Havilland Model DHC- 6 Series Airplanes
aircraft Viking Air Limited DHC-6-100 Airworthiness Directives; de Havilland Model DHC- 6 Series Airplanes
aircraft Viking Air Limited DHC-6-200 Airworthiness Directives; de Havilland Model DHC- 6 Series Airplanes
aircraft Viking Air Limited DHC-6-300 Airworthiness Directives; de Havilland Model DHC- 6 Series Airplanes

Unsafe Condition

Loss of AC power system due to a fault in an AC circuit causing total power loss.

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

Required Actions

Comply with Service Bulletin 6/263 (Rev B) instructions 1 and 2(a) through 2(e), replace slow-blow fuses with Littlefuse or Bussman types as specified, and replace non-compliant inverters prior to further flight.

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

Compliance Time

within the next 250 hours' time in service after the effective date of this AD unless already accomplished

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

Affected Aircraft

de Havilland Model DHC-6 Series Airplanes, Serial Numbers 6 through 289 with Flitetronic Type PC 15 or PC 15A Inverters.

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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