AD 57-12-01

final rule
Data completeness: 60%

Airworthiness Directives; Bell Model 47H1 Helicopters

AD Number
57-12-01
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Unknown
FR Citation
This information is not available.

Applicability

TypeManufacturerModelDetails
aircraft Scotts-Bell 47 Inc 47H-1 Airworthiness Directives; Bell Model 47H1 Helicopters

Unsafe Condition

Possible misalignment in the fore and aft synchronized elevator control pulley quadrant which may cause the control cables to be misaligned and cause chafing.

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

Required Actions

Inspect the synchronized elevator control cables for alinement into the cable groove on the forward 47-267-112-5 pulley quadrant and the aft 47-267-410-1 elevator pulley quadrant. Inspect the forward 47-267-112-5 pulley quadrant support bracket bolt holes for elongation. If misalignment or bolt hole elongation exist, rework as outlined in Bell Service Bulletin No. 111 is required.

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

Compliance Time

as soon as possible but not later than August 1, 1957

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

Affected Aircraft

Bell Model 47H1 Helicopters Serial Numbers 1347 Through 1349 and 1351 Through 1371

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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