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FAA orders · airworthiness directive · current

56-08-01: Pitch Limit Switches

FAA order 56-08-01 is an airworthiness directive. The FAA's subject line: Pitch Limit Switches. System: propeller.

What it applies to as the FAA lists it

Kind of product
Propeller
Makes
Curtiss-Wright Corporation
Models
C632S, C634D, C634S

Dates and paperwork

Docket
Unknown
Status
Current
The FAA's document
Read the order on the FAA's site

The order itself the regulatory text, as published

Show the full text (945 characters)
56-08-01 CURTISS: Applies to All Models C632S, C634D and C634S Propellers. Compliance required as indicated. I. Replace low pitch limit switches P/N 110425 at not more than the following intervals: Douglas DC-6 Series Aircraft 3,500 Hours Lockheed 749 Series Aircraft 3,500 Hours Lockheed 1049 Series Aircraft 3,500 Hours Convair 240 Series Aircraft 1,000 Hours (Curtiss Service Bulletin No. 52 dated December 29, 1949, and appropriate service manuals also cover these recommendations.) II. Disassemble and visually inspect low pitch limit switches P/N 154592 at not more than the same intervals. Inspect for proper switch operation and for mechanical and electrical condition. Failure or malfunction other than normal service wear shall be cause for replacement of switch parts or of the assembly. Switches not revealing adverse conditions may be returned to service. This supersedes Section III of AD 53-05-01.

Source: FAA Dynamic Regulatory System, airworthiness directives. The FAA's document is the authority; the register counts are this site's, from the FAA register of November 6, 2026. Connections as data: /graph/directive/56-08-01.json · aircraft systems.