AD 70-22-07
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| engine | Rolls-Royce Deutschland Ltd & Co KG | Dart 506 | ROLLS-ROYCE Models Dart 506, 510, and 526 Engines |
| engine | Rolls-Royce Deutschland Ltd & Co KG | Dart 510 | ROLLS-ROYCE Models Dart 506, 510, and 526 Engines |
| engine | Rolls-Royce Deutschland Ltd & Co KG | Dart 526 | ROLLS-ROYCE Models Dart 506, 510, and 526 Engines |
Unsafe Condition
Annulus gear failure could lead to loss of propeller control.
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Required Actions
Incorporate Rolls-Royce Modifications 1431 (for Model 506) and 1550 (for Models 510 and 526) per specified service bulletins or FAA-approved equivalents.
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Compliance Time
within the next 500 hours' time in service after the effective date of this AD
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Affected Aircraft
Rolls-Royce Models Dart 506, 510, and 526 engines installed on British Aircraft Corporation Viscount 744 and 745D; and Armstrong Whitworth Argosy 650 Series 101 airplanes.
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Federal Register Abstract
Annulus Gear Failure
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_70-22-07.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 70-22-07 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: ROLLS-ROYCE Models Dart 506, 510, and 526 Engines Subject: Annulus Gear Failure Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 11/23/1970 Make: Rolls-Royce Deutschland Ltd & Co KG Model: Dart 506 | Dart 510 | Dart 526 Product Type: Engine Product Subtype: Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 70-22-07 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1098 AD NUMBER: 70-22-07 SUBJECT HEADING: ROLLS-ROYCE Models Dart 506, 510, and 526 Engines ACTION: SUMMARY: DATES: Effective November 23, 1970. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 70-22-07 ROLLS-ROYCE: Amdt. 39-1098. Applies to Rolls-Royce Dart engines Models 506, 510, and 526, installed on, but not necessarily limited to, British Aircraft Corporation Viscount 744 and 745D; and Armstrong Whitworth Argosy 650 Series 101 airplanes. Compliance is required within the next 500 hours' time in service after the effective date of this AD, unless already accomplished. To prevent the loss of propeller control in the event of an annulus gear failure, accomplish the following: (a) For Rolls-Royce Dart Model 506 engines, incorporate Rolls-Royce Dart Modification 1431 in accordance with Rolls-Royce Dart Aero Engine Service Bulletin Number Da72-297, Revision 7, dated February 20, 1970, or later ARB-approved revision, or an FAA-approved equivalent. (b) For Rolls-Royce Dart Models 510 and 526, incorporate Rolls-Royce Dart Modification 1550 in accordance with Rolls-Royce Dart Aero Engine Service Bulletin Number Da72-348, Revision 9, dated November 28, 1969, or later ARB-approved revision or an FAA-approved equivalent. This amendment becomes effective November 23, 1970. FOOTER:
Document Text
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AD Final Rules - DRS_70-22-07.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 70-22-07 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: ROLLS-ROYCE Models Dart 506, 510, and 526 Engines Subject: Annulus Gear Failure Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 11/23/1970 Make: Rolls-Royce Deutschland Ltd & Co KG Model: Dart 506 | Dart 510 | Dart 526 Product Type: Engine 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: 70-22-07 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1098 AD NUMBER: 70-22-07 SUBJECT HEADING: ROLLS-ROYCE Models Dart 506, 510, and 526 Engines ACTION: SUMMARY: DATES: Effective November 23, 1970. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 70-22-07 ROLLS-ROYCE: Amdt. 39-1098. Applies to Rolls-Royce Dart engines Models 506, 510, and 526, installed on, but not necessarily limited to, British Aircraft Corporation Viscount 744 and 745D; and Armstrong Whitworth Argosy 650 Series 101 airplanes. Compliance is required within the next 500 hours' time in service after the effective date of this AD, unless already accomplished. To prevent the loss of propeller control in the event of an annulus gear failure, accomplish the following: (a) For Rolls-Royce Dart Model 506 engines, incorporate Rolls-Royce Dart Modification 1431 in accordance with Rolls-Royce Dart Aero Engine Service Bulletin Number Da72-297, Revision 7, dated February 20, 1970, or later ARB-approved revision, or an FAA-approved equivalent. (b) For Rolls-Royce Dart Models 510 and 526, incorporate Rolls-Royce Dart Modification 1550 in accordance with Rolls-Royce Dart Aero Engine Service Bulletin Number Da72-348, Revision 9, dated November 28, 1969, or later ARB-approved revision or an FAA-approved equivalent. This amendment becomes effective November 23, 1970. FOOTER:
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Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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