AD 70-05-06
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Hartzell Propeller, Inc. | HC-B3T | HARTZELL PROPELLERS Models HC-B3TN-5C Series Propellers |
| propeller | Hartzell Propeller, Inc. | HC-B3T | HARTZELL PROPELLERS Models HC-B3TN-5C Series Propellers |
Unsafe Condition
Cracks in the inner surface of the pilot tube hole and scratches, gouges, or tool marks in the area of minimum wall thickness of Hartzell T10176( ) and T10176H( ) type blades installed on HC-B3TN-5C series propellers.
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Required Actions
Inspect blades by removing them from the propeller and the smaller needle bearing, clean and inspect the pilot tube hole for cracks using dye penetrant, visually inspect for scratches, gouges, or tool marks, and check wall thickness per Hartzell Bulletin No. 95. Replace blades with cracks, defects, or insufficient wall thickness before further flight.
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Compliance Time
Within the next 50 hours after the effective date (March 11, 1970) for propellers with 700+ hours, or prior to 750 hours in service for those with less than 700 hours. Reinspect every 1500 hours in service from the last inspection.
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Affected Aircraft
Hartzell Propeller, Inc. HC-B3TN-5C series propellers with T10176( ) or T10176H( ) type blades used on AiResearch TPE331-( ) engines.
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Federal Register Abstract
Blade
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_70-05-06.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 70-05-06 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: HARTZELL PROPELLERS Models HC-B3TN-5C Series Propellers Subject: Blade Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 03/11/1970 Make: Hartzell Propeller, Inc. Model: HC-B3T Product Type: Propeller Product Subtype: Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 70-05-06 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-954 AD NUMBER: 70-05-06 SUBJECT HEADING: HARTZELL PROPELLERS Models HC-B3TN-5C Series Propellers ACTION: SUMMARY: DATES: Effective March 11, 1970. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 70-05-06 HARTZELL PROPELLERS: Amdt. 39-954. Applies to Hartzell T10176( ) and T10176H( ) type blades installed on Hartzell HC-B3TN-5C series propellers used on AiResearch TPE331-( ) type engines. Compliance required as indicated, unless already accomplished. a. Propellers with 700 or more total hours in service, inspect in accordance with paragraphs (c) and (d) within the next 50 hours after the effective date of this AD, and reinspect in accordance with paragraph (c) every 1500 hours in service from the last inspection. b. Propellers with less than 700 total hours in service inspect in accordance with paragraphs (c) and (d) prior to the accumulation of 750 hours in service and reinspect in accordance with paragraph (c) every 1500 hours in service from the last inspection. c. Remove the blades from the propeller and the smaller needle bearing from the bottom of the blade pilot tube hole. In accordance with Hartzell Bulletin No. 95 dated 7 January 1970, or FAA approved equivalent procedure, clean and inspect the inner surface of the pilot tube hole for cracks by dye penetrant method and visually inspect for scratches, gouges or tool marks in the area of minimum wall thickness. Replace before further flight any cracked blade or blade having scratches, gouges, or tool marks in the critical radius with a blade which has been inspected in accordance with this AD and found satisfactory. d. Inspect the blade for minimum wall thickness in the shank area in accordance with Hartzell Bulletin No. 95 dated 7 January 1970. Replace before further flight any blade having a wall thickness less than that noted in Bulletin No. 95 with a blade inspected in accordance with this AD and found satisfactory. e. Upon submission of substantiating data through an FAA Maintenance Inspector, the Chief, Engineering and Manufacturing Branch, FAA Eastern Region may adjust repetitive inspection intervals specified in this AD. (Hartzell Bulletin No. 95 dated 7 January 1970 and Manual 118A cover this subject.) This amendment is effective March 11, 1970. FOOTER:
Document Text
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AD Final Rules - DRS_70-05-06.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 70-05-06 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: HARTZELL PROPELLERS Models HC-B3TN-5C Series Propellers Subject: Blade Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 03/11/1970 Make: Hartzell Propeller, Inc. Model: HC-B3T 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: 70-05-06 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-954 AD NUMBER: 70-05-06 SUBJECT HEADING: HARTZELL PROPELLERS Models HC-B3TN-5C Series Propellers ACTION: SUMMARY: DATES: Effective March 11, 1970. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 70-05-06 HARTZELL PROPELLERS: Amdt. 39-954. Applies to Hartzell T10176( ) and T10176H( ) type blades installed on Hartzell HC-B3TN-5C series propellers used on AiResearch TPE331-( ) type engines. Compliance required as indicated, unless already accomplished. a. Propellers with 700 or more total hours in service, inspect in accordance with paragraphs (c) and (d) within the next 50 hours after the effective date of this AD, and reinspect in accordance with paragraph (c) every 1500 hours in service from the last inspection. b. Propellers with less than 700 total hours in service inspect in accordance with paragraphs (c) and (d) prior to the accumulation of 750 hours in service and reinspect in accordance with paragraph (c) every 1500 hours in service from the last inspection. c. Remove the blades from the propeller and the smaller needle bearing from the bottom of the blade pilot tube hole. In accordance with Hartzell Bulletin No. 95 dated 7 January 1970, or FAA approved equivalent procedure, clean and inspect the inner surface of the pilot tube hole for cracks by dye penetrant method and visually inspect for scratches, gouges or tool marks in the area of minimum wall thickness. Replace before further flight any cracked blade or blade having scratches, gouges, or tool marks in the critical radius with a blade which has been inspected in accordance with this AD and found satisfactory. d. Inspect the blade for minimum wall thickness in the shank area in accordance with Hartzell Bulletin No. 95 dated 7 January 1970. Replace before further flight any blade having a wall thickness less than that noted in Bulletin No. 95 with a blade inspected in accordance with this AD and found satisfactory. e. Upon submission of substantiating data through an FAA Maintenance Inspector, the Chief, Engineering and Manufacturing Branch, FAA Eastern Region may adjust repetitive inspection intervals specified in this AD. (Hartzell Bulletin No. 95 dated 7 January 1970 and Manual 118A cover this subject.) This amendment is effective March 11, 1970. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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