AD 64-27-04
final rule
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Boeing Defense & Space Group | Heli-Crane Corporation | Marrs Joe G. | Risley Lester W. | Wright Kevin | 42A | Airworthiness Directives; VERTOL Models H-21 and 42 Series Helicopters |
| aircraft | Boeing Defense & Space Group | Heli-Crane Corporation | Marrs Joe G. | Risley Lester W. | Wright Kevin | 42B | Airworthiness Directives; VERTOL Models H-21 and 42 Series Helicopters |
| aircraft | Boeing Defense & Space Group | Heli-Crane Corporation | Marrs Joe G. | Risley Lester W. | Wright Kevin | H21A | Airworthiness Directives; VERTOL Models H-21 and 42 Series Helicopters |
| aircraft | Boeing Defense & Space Group | Heli-Crane Corporation | Marrs Joe G. | Risley Lester W. | Wright Kevin | H-21B | Airworthiness Directives; VERTOL Models H-21 and 42 Series Helicopters |
Unsafe Condition
Fatigue failure of wood rotor blade root socket, P/N 22R1364-1, due to cracks in the slot area between the inboard clamp bolt and the relief hole at the inboard end of the slot.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Conduct daily visual inspections with an 8-power magnifying glass for cracks in the slot area. Replace cracked sockets before further flight. Retire sockets with 725+ hours' time in service by 25 hours after AD effective date, and retire others at 750 hours' time in service.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Compliance required as indicated. The AD is effective December 10, 1964.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
VERTOL Models H-21 and 42 Series Helicopters with wood rotor blade root sockets, P/N 22R1364-1.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Wood Rotor Blade Root Socket
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_64-27-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 64-27-04 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; VERTOL Models H-21 and 42 Series Helicopters Subject: Wood Rotor Blade Root Socket Status: Current Citation: Federal Register: December 5, 1964 Citation Publish Date: 12/05/1964 Effective Date: 12/10/1964 Make: Boeing Defense & Space Group | Heli-Crane Corporation | Marrs Joe G. | Risley Lester W. | Wright Kevin Model: 42A | 42B | H21A | H-21B Product Type: Aircraft Product Subtype: Rotorcraft Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: AIR-700: Compliance & Airworthiness Division Office of Primary Responsibility: AIR-720: Operational Safety Branch CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 64-27-04 CITATION: [Federal Register: December 5, 1964] PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-9 AD NUMBER: 64-27-04 SUBJECT HEADING: Airworthiness Directives; VERTOL Models H-21 and 42 Series Helicopters ACTION: SUMMARY: DATES: Effective December 10, 1964. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 64-27-04 VERTOL: Amdt. 39-9 Part 39 (New) Federal Register December 5, 1964. Applies to Models H-21 and 42 Series Helicopters. Compliance required as indicated. As a result of a fatigue failure of a wood rotor blade root socket, P/N 22R1364-1, accomplish the following: (a) Conduct a daily visual inspection, using a magnifying glass of at least 8-power, of wood rotor blade root sockets, P/N 22R1364-1, with 750 or more hours' time in service as of the effective date of this AD, for cracks in the slot area between the inboard clamp bolt and the relief hole at the inboard end of the slot while supporting the rotor blade tip so that the blade does not rest on the droop stop. (b) Replace any cracked socket before further flight. (c) Within 25 hours' time in service after the effective date of this AD retire from service all wood rotor blade root sockets, P/N 22R1364-1, having 725 or more hours' time in service on the effective date of this AD. (d) Upon the accumulation of 750 hours' time in service, retire from service all wood rotor blade root sockets, P/N 22R1364-1, having less than 725 hours' time in service on the effective date of this AD. This directive effective December 10, 1964. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_64-27-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 64-27-04 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; VERTOL Models H-21 and 42 Series Helicopters Subject: Wood Rotor Blade Root Socket Status: Current Citation: Federal Register: December 5, 1964 Citation Publish Date: 12/05/1964 Effective Date: 12/10/1964 Make: Boeing Defense & Space Group | Heli-Crane Corporation | Marrs Joe G. | Risley Lester W. | Wright Kevin Model: 42A | 42B | H21A | H-21B Product Type: Aircraft Product Subtype: Rotorcraft Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: AIR-700: Compliance & Airworthiness Division Office of Primary Responsibility: AIR-720: Operational Safety Branch CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 64-27-04 CITATION: [Federal Register: December 5, 1964] PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-9 AD NUMBER: 64-27-04 SUBJECT HEADING: Airworthiness Directives; VERTOL Models H-21 and 42 Series Helicopters ACTION: SUMMARY: DATES: Effective December 10, 1964. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 64-27-04 VERTOL: Amdt. 39-9 Part 39 (New) Federal Register December 5, 1964. Applies to Models H-21 and 42 Series Helicopters. Compliance required as indicated. As a result of a fatigue failure of a wood rotor blade root socket, P/N 22R1364-1, accomplish the following: (a) Conduct a daily visual inspection, using a magnifying glass of at least 8-power, of wood rotor blade root sockets, P/N 22R1364-1, with 750 or more hours' time in service as of the effective date of this AD, for cracks in the slot area between the inboard clamp bolt and the relief hole at the inboard end of the slot while supporting the rotor blade tip so that the blade does not rest on the droop stop. (b) Replace any cracked socket before further flight. (c) Within 25 hours' time in service after the effective date of this AD retire from service all wood rotor blade root sockets, P/N 22R1364-1, having 725 or more hours' time in service on the effective date of this AD. (d) Upon the accumulation of 750 hours' time in service, retire from service all wood rotor blade root sockets, P/N 22R1364-1, having less than 725 hours' time in service on the effective date of this AD. This directive effective December 10, 1964. FOOTER:
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