AD 52-01-07
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Scotts-Bell 47 Inc | 47D1 | Airworthiness Directives; Bell Model 47D1 Helicopters |
Unsafe Condition
The possibility of throwing blades in flight due to the existing 47-661-030-1 hub assembly in the cooling fan.
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Required Actions
Rework the existing 47-661-030-1 hub, reassemble the fan using parts from the modification kit, and balance the modified fan assembly (P/N 47-661-036-5) according to specified procedures before installation.
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Compliance Time
At the next 300-hour overhaul, but not later than March 1, 1952.
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Affected Aircraft
All Model 47D1 Helicopters having 47-661-030-1 Hub Assembly in the Cooling Fan.
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Federal Register Abstract
Engine Cooling Fan
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_52-01-07.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 52-01-07 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Bell Model 47D1 Helicopters Subject: Engine Cooling Fan Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Scotts-Bell 47 Inc Model: 47D1 Product Type: Aircraft Product Subtype: Rotorcraft Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 52-01-07 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 52-01-07 SUBJECT HEADING: Airworthiness Directives; Bell Model 47D1 Helicopters ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 52-01-07 BELL: Applies to All Model 47D1 Helicopters Having 47-661-030-1 Hub Assembly in the Cooling Fan. Refer to Bell Service Bulletin No. 72. Compliance required at the next 300-hour overhaul, but not later than March 1, 1952. To reduce the possibility of throwing blades in flight, rework the existing 47-661-030-1 hub and reassemble the fan using the parts provided in the modification kit. (Note: Do not install old fan blades.) Balance modified fan assembly (assigned P/N 47-661-036-5) in accordance with specified erection and maintenance procedure prior to installation. (Bell Service Bulletin No. 82 covers this same subject.) FOOTER:
Document Text
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AD Final Rules - DRS_52-01-07.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 52-01-07 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Bell Model 47D1 Helicopters Subject: Engine Cooling Fan Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Scotts-Bell 47 Inc Model: 47D1 Product Type: Aircraft Product Subtype: Rotorcraft Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 52-01-07 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 52-01-07 SUBJECT HEADING: Airworthiness Directives; Bell Model 47D1 Helicopters ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 52-01-07 BELL: Applies to All Model 47D1 Helicopters Having 47-661-030-1 Hub Assembly in the Cooling Fan. Refer to Bell Service Bulletin No. 72. Compliance required at the next 300-hour overhaul, but not later than March 1, 1952. To reduce the possibility of throwing blades in flight, rework the existing 47-661-030-1 hub and reassemble the fan using the parts provided in the modification kit. (Note: Do not install old fan blades.) Balance modified fan assembly (assigned P/N 47-661-036-5) in accordance with specified erection and maintenance procedure prior to installation. (Bell Service Bulletin No. 82 covers this same subject.) FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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