AD 73-19-04
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Scotts-Bell 47 Inc | 47 | Airworthiness Directives; Bell Model 47 Series Helicopters |
| aircraft | Scotts-Bell 47 Inc | 47B | Airworthiness Directives; Bell Model 47 Series Helicopters |
| aircraft | Scotts-Bell 47 Inc | 47B3 | Airworthiness Directives; Bell Model 47 Series Helicopters |
| aircraft | Scotts-Bell 47 Inc | 47D | Airworthiness Directives; Bell Model 47 Series Helicopters |
| aircraft | Scotts-Bell 47 Inc | 47D1 | Airworthiness Directives; Bell Model 47 Series Helicopters |
| aircraft | Scotts-Bell 47 Inc | 47E | Airworthiness Directives; Bell Model 47 Series Helicopters |
| aircraft | Scotts-Bell 47 Inc | 47G | Airworthiness Directives; Bell Model 47 Series Helicopters |
| aircraft | Scotts-Bell 47 Inc | 47G-2 | Airworthiness Directives; Bell Model 47 Series Helicopters |
| aircraft | Scotts-Bell 47 Inc | 47G-2A | Airworthiness Directives; Bell Model 47 Series Helicopters |
| aircraft | Scotts-Bell 47 Inc | 47G-2A-1 | Airworthiness Directives; Bell Model 47 Series Helicopters |
| aircraft | Scotts-Bell 47 Inc | 47G-3 | Airworthiness Directives; Bell Model 47 Series Helicopters |
| aircraft | Scotts-Bell 47 Inc | 47G-3B | Airworthiness Directives; Bell Model 47 Series Helicopters |
| aircraft | Scotts-Bell 47 Inc | 47G-3B-1 | Airworthiness Directives; Bell Model 47 Series Helicopters |
| aircraft | Scotts-Bell 47 Inc | 47G-3B-2 | Airworthiness Directives; Bell Model 47 Series Helicopters |
| aircraft | Scotts-Bell 47 Inc | 47G-3B-2A | Airworthiness Directives; Bell Model 47 Series Helicopters |
| aircraft | Scotts-Bell 47 Inc | 47G-4 | Airworthiness Directives; Bell Model 47 Series Helicopters |
| aircraft | Scotts-Bell 47 Inc | 47G-4A | Airworthiness Directives; Bell Model 47 Series Helicopters |
| aircraft | Scotts-Bell 47 Inc | 47G-5 | Airworthiness Directives; Bell Model 47 Series Helicopters |
| aircraft | Scotts-Bell 47 Inc | 47G-5A | Airworthiness Directives; Bell Model 47 Series Helicopters |
| aircraft | Scotts-Bell 47 Inc | 47H-1 | Airworthiness Directives; Bell Model 47 Series Helicopters |
| aircraft | Scotts-Bell 47 Inc | 47J | Airworthiness Directives; Bell Model 47 Series Helicopters |
| aircraft | Scotts-Bell 47 Inc | 47J-2 | Airworthiness Directives; Bell Model 47 Series Helicopters |
| aircraft | Scotts-Bell 47 Inc | 47J-2A | Airworthiness Directives; Bell Model 47 Series Helicopters |
| aircraft | Scotts-Bell 47 Inc | 47K | Airworthiness Directives; Bell Model 47 Series Helicopters |
Unsafe Condition
Fatigue cracks may develop in the main rotor blade grip thread relief fillet and root radius of the 4 1/2 inch diameter threads due to sharp notches, nicks, or tool marks.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Inspect the grip thread relief fillet for smooth finish and absence of nicks or tool marks, inspect the root radius of the 4 1/2 inch diameter threads for sharp notches, and replace the grip before next flight if deficiencies are found.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
within the next 100 hours' time in service after the effective date of this A.D., unless already accomplished
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Affected Aircraft
Scotts-Bell 47 Inc Model 47 series helicopters equipped with main rotor blade grips P/N 47-120-135-1, -2, -3 or P/N 47-120-252-1, -3
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Main Rotor Blade Grip
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_73-19-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 73-19-04 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Bell Model 47 Series Helicopters Subject: Main Rotor Blade Grip Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 10/10/1973 Make: Scotts-Bell 47 Inc Model: 47 | 47B | 47B3 | 47D | 47D1 | 47E | 47G | 47G-2 | 47G-2A | 47G-2A-1 | 47G-3 | 47G-3B | 47G-3B-1 | 4...Show more 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: 73-19-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1711 AD NUMBER: 73-19-04 SUBJECT HEADING: Airworthiness Directives; Bell Model 47 Series Helicopters ACTION: SUMMARY: DATES: Effective October 10, 1973. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 73-19-04 BELL: Amdt. 39-1711. Applies to Model 47 series helicopters certificated in all categories that are equipped with main rotor blade grips, P/N 47-120-135-1, -2, -3 or P/N 47- 120-252-1, -3. Compliance required within the next 100 hours' time in service after the effective date of this A.D., unless already accomplished. To prevent possible fatigue cracks from developing, accomplish the following for each main rotor blade grip: (a) Inspect the grip thread relief fillet. The inboard radius and bottom of the fillet must have a smooth finish and be free of nicks or sharp tool marks (Ref. Figure 1-22 of Bell 47D- 1, 47G and 47G-2 Maintenance and Overhaul Instructions). (b) Inspect the root radius of the 4 1/2 inch diameter threads for sharp notches. The root radius must be smooth and free of sharp notches or grooves. (c) If the grip thread relief fillet is not as specified in subparagraph (a) or has nicks or sharp tool marks, or if the thread root radius has a sharp notch or groove, replace the affected grip prior to next flight, except the helicopter may be flown in accordance with FAR 21.197 to a base where the grip may be replaced. This amendment becomes effective October 10, 1973. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_73-19-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 73-19-04 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Bell Model 47 Series Helicopters Subject: Main Rotor Blade Grip Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 10/10/1973 Make: Scotts-Bell 47 Inc Model: 47 | 47B | 47B3 | 47D | 47D1 | 47E | 47G | 47G-2 | 47G-2A | 47G-2A-1 | 47G-3 | 47G-3B | 47G-3B-1 | 4...Show more 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: 73-19-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1711 AD NUMBER: 73-19-04 SUBJECT HEADING: Airworthiness Directives; Bell Model 47 Series Helicopters ACTION: SUMMARY: DATES: Effective October 10, 1973. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 73-19-04 BELL: Amdt. 39-1711. Applies to Model 47 series helicopters certificated in all categories that are equipped with main rotor blade grips, P/N 47-120-135-1, -2, -3 or P/N 47- 120-252-1, -3. Compliance required within the next 100 hours' time in service after the effective date of this A.D., unless already accomplished. To prevent possible fatigue cracks from developing, accomplish the following for each main rotor blade grip: (a) Inspect the grip thread relief fillet. The inboard radius and bottom of the fillet must have a smooth finish and be free of nicks or sharp tool marks (Ref. Figure 1-22 of Bell 47D- 1, 47G and 47G-2 Maintenance and Overhaul Instructions). (b) Inspect the root radius of the 4 1/2 inch diameter threads for sharp notches. The root radius must be smooth and free of sharp notches or grooves. (c) If the grip thread relief fillet is not as specified in subparagraph (a) or has nicks or sharp tool marks, or if the thread root radius has a sharp notch or groove, replace the affected grip prior to next flight, except the helicopter may be flown in accordance with FAR 21.197 to a base where the grip may be replaced. This amendment becomes effective October 10, 1973. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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