AD 78-09-05

final rule
Data completeness: 70%

Airworthiness Directives; CESSNA Models 336, 337, 337A, 337B, T337B, 337C, T337C, 337D, T337D, 337E, T337E, 337F, T337F, T337G, 337H, T337H, T337G, P337H and M337B Airplanes

AD Number
78-09-05
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Unknown
FR Citation
This information is not available.

Applicability

TypeManufacturerModelDetails
aircraft Cessna Aircraft Company 336 Airworthiness Directives; CESSNA Models 336, 337, 337A, 337B, T337B, 337C, T337C, 337D, T337D, 337E, T337E, 337F, T337F, T337G, 337H, T337H, T337G, P337H and M337B Airplanes
aircraft Cessna Aircraft Company 337 Airworthiness Directives; CESSNA Models 336, 337, 337A, 337B, T337B, 337C, T337C, 337D, T337D, 337E, T337E, 337F, T337F, T337G, 337H, T337H, T337G, P337H and M337B Airplanes
aircraft Cessna Aircraft Company 337A Airworthiness Directives; CESSNA Models 336, 337, 337A, 337B, T337B, 337C, T337C, 337D, T337D, 337E, T337E, 337F, T337F, T337G, 337H, T337H, T337G, P337H and M337B Airplanes
aircraft Cessna Aircraft Company 337B Airworthiness Directives; CESSNA Models 336, 337, 337A, 337B, T337B, 337C, T337C, 337D, T337D, 337E, T337E, 337F, T337F, T337G, 337H, T337H, T337G, P337H and M337B Airplanes
aircraft Cessna Aircraft Company 337C Airworthiness Directives; CESSNA Models 336, 337, 337A, 337B, T337B, 337C, T337C, 337D, T337D, 337E, T337E, 337F, T337F, T337G, 337H, T337H, T337G, P337H and M337B Airplanes
aircraft Cessna Aircraft Company 337D Airworthiness Directives; CESSNA Models 336, 337, 337A, 337B, T337B, 337C, T337C, 337D, T337D, 337E, T337E, 337F, T337F, T337G, 337H, T337H, T337G, P337H and M337B Airplanes
aircraft Cessna Aircraft Company 337E Airworthiness Directives; CESSNA Models 336, 337, 337A, 337B, T337B, 337C, T337C, 337D, T337D, 337E, T337E, 337F, T337F, T337G, 337H, T337H, T337G, P337H and M337B Airplanes
aircraft Cessna Aircraft Company 337F Airworthiness Directives; CESSNA Models 336, 337, 337A, 337B, T337B, 337C, T337C, 337D, T337D, 337E, T337E, 337F, T337F, T337G, 337H, T337H, T337G, P337H and M337B Airplanes
aircraft Cessna Aircraft Company 337G Airworthiness Directives; CESSNA Models 336, 337, 337A, 337B, T337B, 337C, T337C, 337D, T337D, 337E, T337E, 337F, T337F, T337G, 337H, T337H, T337G, P337H and M337B Airplanes
aircraft Cessna Aircraft Company 337H Airworthiness Directives; CESSNA Models 336, 337, 337A, 337B, T337B, 337C, T337C, 337D, T337D, 337E, T337E, 337F, T337F, T337G, 337H, T337H, T337G, P337H and M337B Airplanes

Unsafe Condition

Cracking of the wing front and rear spar lower caps, front spar web and web doubler.

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

Required Actions

Inspect the right and left wing front and rear spar lower cap and front spar web and web doubler at specified intervals using eddy current and dye penetrant methods. Replace cracked components in both wings before return to service. Report findings to FAA and adjust inspection intervals as allowed.

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

Compliance Time

Within 25 hours time-in-service after the effective date of this AD for airplanes not previously inspected, or within 500 hours time-in-service after the last inspection under prior ADs. Repetitive inspections every 500 hours for non-pressurized (5,000+ hours) or pressurized (10,000+ hours) airplanes, or 300 hours for those with low altitude operations as urged.

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

Affected Aircraft

Cessna Models 336, 337, 337A, 337B, T337B, 337C, T337C, 337D, T337D, 337E, T337E, 337F, T337F, T337G, 337H, T337H, P337H, M337B with specific serial ranges: 336-0001-0195, 337-0001-1193, 33701194-33701852, P3370001-P3370313, and all M337B serial numbers.

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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