AD 59-18-03
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Curtiss-Wright Corporation | C634S | CURTISS Models C634S-C400 and C634S-C500 Series Propellers |
| propeller | Curtiss-Wright Corporation | C634S | CURTISS Models C634S-C400 and C634S-C500 Series Propellers |
Unsafe Condition
Peculiar wear of power unit motor and mating speed reducer splines in Curtiss C634S-C400 and C634S-C500 Series propellers has been observed at a time short of a full overhaul period.
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Required Actions
Install a new motor rotor assembly with a longer shaft and larger pitch diameter splines, along with a new mating splined sleeve and high speed drive gear. Modify the 145295-2 power unit assembly to the 163308 power unit assembly.
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Compliance Time
at first propeller overhaul after January 1, 1960, but not later than May 1, 1960
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Affected Aircraft
Curtiss-Wright Corporation Models C634S-C400 and C634S-C500 Series Propellers, all serial numbers
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Federal Register Abstract
Power Unit Assembly
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_59-18-03.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 59-18-03 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: CURTISS Models C634S-C400 and C634S-C500 Series Propellers Subject: Power Unit Assembly Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Curtiss-Wright Corporation Model: C634S Product Type: Propeller Product Subtype: Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 59-18-03 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 59-18-03 SUBJECT HEADING: CURTISS Models C634S-C400 and C634S-C500 Series Propellers ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 59-18-03 CURTISS: Applies to All Models C634S-C400 and C634S-C500 Series Propellers. Compliance required at first propeller overhaul after January 1, 1960, but not later than May 1,1960. Peculiar wear of power unit motor and mating speed reducer splines in Curtiss C634S- C400 and C634S-C500 Series propellers has been observed at a time short of a full overhaul period. In order to minimize the possibility of such occurrences, provide a new motor rotor assembly which incorporates a longer shaft with splines of a larger pitch diameter and a new mating splined sleeve and high speed drive gear. Modification of the 145295-2 power unit assembly in Curtiss C634S-C400 and C634S-C500 Series propellers to the 163308 power unit assembly accomplishes the desired objective. (Curtiss Service Bulletin No. C-24 covers this same subject.) Compliance with AD 59-07-01 is no longer required after compliance with this AD. FOOTER:
Document Text
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AD Final Rules - DRS_59-18-03.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 59-18-03 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: CURTISS Models C634S-C400 and C634S-C500 Series Propellers Subject: Power Unit Assembly Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Curtiss-Wright Corporation Model: C634S Product Type: Propeller Product Subtype: Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 59-18-03 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 59-18-03 SUBJECT HEADING: CURTISS Models C634S-C400 and C634S-C500 Series Propellers ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 59-18-03 CURTISS: Applies to All Models C634S-C400 and C634S-C500 Series Propellers. Compliance required at first propeller overhaul after January 1, 1960, but not later than May 1,1960. Peculiar wear of power unit motor and mating speed reducer splines in Curtiss C634S- C400 and C634S-C500 Series propellers has been observed at a time short of a full overhaul period. In order to minimize the possibility of such occurrences, provide a new motor rotor assembly which incorporates a longer shaft with splines of a larger pitch diameter and a new mating splined sleeve and high speed drive gear. Modification of the 145295-2 power unit assembly in Curtiss C634S-C400 and C634S-C500 Series propellers to the 163308 power unit assembly accomplishes the desired objective. (Curtiss Service Bulletin No. C-24 covers this same subject.) Compliance with AD 59-07-01 is no longer required after compliance with this AD. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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Related Airworthiness Directives
63-24-01
final ruleCURTISS-WRIGHT Models C634S-C400 through -C499 and C634S-C500 through -C599 Series Propellers
Unsafe Condition: Failures of P/N 142080-1 threaded-type brake assemblies causing propeller malfunction.
56-08-01
final ruleCURTISS Models C632S, C634D and C634S Propellers
Unsafe Condition: Failure or malfunction of low pitch limit switches P/N 110425 and P/N 154592 beyond normal service wear could result in improper pitch control or loss of pitch limitation function.
59-07-01
final ruleCURTISS Models C634S-C400 and C634S-C500 Series Propellers
Unsafe Condition: Excessive wear of power unit motor and mating speed reducer splines in Curtiss C634S-C400 and C634S-C500 Series propellers has been observed at a time short of a full overhaul period.