AD 64-28-01
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Hartzell Propeller, Inc. | HC-12X20-1 | HARTZELL Models HC-12X20-1, -2, -3, -5, and -7B Propellers |
| aircraft | Hartzell Propeller, Inc. | HC-12X20-2 | HARTZELL Models HC-12X20-1, -2, -3, -5, and -7B Propellers |
| aircraft | Hartzell Propeller, Inc. | HC-12X20-3 | HARTZELL Models HC-12X20-1, -2, -3, -5, and -7B Propellers |
| aircraft | Hartzell Propeller, Inc. | HC-12X20-5 | HARTZELL Models HC-12X20-1, -2, -3, -5, and -7B Propellers |
| aircraft | Hartzell Propeller, Inc. | HC-12X20-7 | HARTZELL Models HC-12X20-1, -2, -3, -5, and -7B Propellers |
| propeller | Hartzell Propeller, Inc. | HC-12X20-1 | HARTZELL Models HC-12X20-1, -2, -3, -5, and -7B Propellers |
| propeller | Hartzell Propeller, Inc. | HC-12X20-2 | HARTZELL Models HC-12X20-1, -2, -3, -5, and -7B Propellers |
| propeller | Hartzell Propeller, Inc. | HC-12X20-3 | HARTZELL Models HC-12X20-1, -2, -3, -5, and -7B Propellers |
| propeller | Hartzell Propeller, Inc. | HC-12X20-5 | HARTZELL Models HC-12X20-1, -2, -3, -5, and -7B Propellers |
| propeller | Hartzell Propeller, Inc. | HC-12X20-7 | HARTZELL Models HC-12X20-1, -2, -3, -5, and -7B Propellers |
Unsafe Condition
Failure of a hub spider can result in loss of propeller blade.
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Required Actions
Visually inspect hub spiders for cracks in accordance with Hartzell Service Bulletin No. 32 amended August 11, 1964, within 10 hours' time in service after AD effective date. Replace cracked parts before further flight. Replace hub spiders based on accumulated time in service: those with less than 400 hours must be replaced before 500 hours, and those with 400+ hours must be replaced within 100 hours after AD effective date.
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Compliance Time
Compliance required as indicated.
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Affected Aircraft
Hartzell Propeller, Inc. Models HC-12X20-1, -2, -3, -5, and -7B Propellers equipped with C-49-2B and C-49-2C Hub Spiders serial numbers 4220 through 5400 installed on Downer (Republic) RC-3; Navion, Navion A; and Grumman G-44 Series Aircraft.
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Federal Register Abstract
Hub Spiders
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_64-28-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 64-28-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: HARTZELL Models HC-12X20-1, -2, -3, -5, and -7B Propellers Subject: Hub Spiders Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 06/18/1965 Make: Hartzell Propeller, Inc. Model: HC-12X20-1 | HC-12X20-2 | HC-12X20-3 | HC-12X20-5 | HC-12X20-7 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: 64-28-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-14 AD NUMBER: 64-28-01 SUBJECT HEADING: HARTZELL Models HC-12X20-1, -2, -3, -5, and -7B Propellers ACTION: SUMMARY: DATES: Effective June 18, 1965. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 64-28-01 HARTZELL: Amdt. 39-14 Part 39 Federal Register December 16, 1964. Applies to Models HC-12X20-1, -2, -3, -5, and -7B Propellers Equipped with C-49-2B and C-49-2C Hub Spiders Having Serial Numbers 4220 through 5400 Installed on Downer (Republic) RC-3; Navion, Navion A; and Grumman G-44 Series Aircraft. Compliance required as indicated. As a result of loss of propeller blade due to failure of a hub spider, accomplish the following: (a) Visually inspect propeller hub spiders for cracks in accordance with Hartzell Service Bulletin No. 32 amended August 11, 1964, within 10 hours' time in service after the effective date of this AD, and at intervals thereafter not to exceed 25 hours' time in service from the last inspection until modification in accordance with Hartzell Service Bulletin No. 32 amended August 11, 1964, is accomplished. Replace cracked parts before further flight (b) Replace propeller hub spiders having accumulated less than 400 hours' time in service since new or last overhaul in accordance with Hartzell Service Bulletin No. 32 amended August 11, 1964, prior to the accumulation of 500 hours' total time in service since new or last overhaul. (c) Replace propeller hub spiders having accumulated 400 or more hours' time in service since new or last overhaul in accordance with Hartzell Service Bulletin No. 32 amended August 11, 1964, prior to the accumulation of 100 hours' time in service after the effective date of this AD. (Hartzell Service Bulletin No. 32 dated March 9, 1955, amended August 11, 1964, covers this subject.) This directive effective January 15, 1965 Revised April 8, 1965. Revised June 18, 1965. FOOTER:
Document Text
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AD Final Rules - DRS_64-28-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 64-28-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: HARTZELL Models HC-12X20-1, -2, -3, -5, and -7B Propellers Subject: Hub Spiders Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 06/18/1965 Make: Hartzell Propeller, Inc. Model: HC-12X20-1 | HC-12X20-2 | HC-12X20-3 | HC-12X20-5 | HC-12X20-7 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: 64-28-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-14 AD NUMBER: 64-28-01 SUBJECT HEADING: HARTZELL Models HC-12X20-1, -2, -3, -5, and -7B Propellers ACTION: SUMMARY: DATES: Effective June 18, 1965. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 64-28-01 HARTZELL: Amdt. 39-14 Part 39 Federal Register December 16, 1964. Applies to Models HC-12X20-1, -2, -3, -5, and -7B Propellers Equipped with C-49-2B and C-49-2C Hub Spiders Having Serial Numbers 4220 through 5400 Installed on Downer (Republic) RC-3; Navion, Navion A; and Grumman G-44 Series Aircraft. Compliance required as indicated. As a result of loss of propeller blade due to failure of a hub spider, accomplish the following: (a) Visually inspect propeller hub spiders for cracks in accordance with Hartzell Service Bulletin No. 32 amended August 11, 1964, within 10 hours' time in service after the effective date of this AD, and at intervals thereafter not to exceed 25 hours' time in service from the last inspection until modification in accordance with Hartzell Service Bulletin No. 32 amended August 11, 1964, is accomplished. Replace cracked parts before further flight (b) Replace propeller hub spiders having accumulated less than 400 hours' time in service since new or last overhaul in accordance with Hartzell Service Bulletin No. 32 amended August 11, 1964, prior to the accumulation of 500 hours' total time in service since new or last overhaul. (c) Replace propeller hub spiders having accumulated 400 or more hours' time in service since new or last overhaul in accordance with Hartzell Service Bulletin No. 32 amended August 11, 1964, prior to the accumulation of 100 hours' time in service after the effective date of this AD. (Hartzell Service Bulletin No. 32 dated March 9, 1955, amended August 11, 1964, covers this subject.) This directive effective January 15, 1965 Revised April 8, 1965. Revised June 18, 1965. FOOTER:
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Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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