AD 60-21-01
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| engine | Rolls-Royce Corporation | 501-D13 | ALLISON Model 501-D13 Series Engines |
| engine | Rolls-Royce Corporation | 501-D13A | ALLISON Model 501-D13 Series Engines |
| engine | Rolls-Royce Corporation | 501-D13D | ALLISON Model 501-D13 Series Engines |
| engine | Rolls-Royce Corporation | 501-D13E | ALLISON Model 501-D13 Series Engines |
| engine | Rolls-Royce Corporation | 501-D13H | ALLISON Model 501-D13 Series Engines |
Unsafe Condition
Rubbing of the torquemeter housing by the torquemeter reference shaft can result in complete separation of the housing into two sections.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Install a mid-bearing torquemeter assembly, part number 6823900, identified by a 1/2-inch by 2 1/2-inch blue stripe on the forward bevel of the housing.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
at next overhaul of engine, power section or torquemeter, whichever occurs first, after the effective date of this AD
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Rolls-Royce Corporation Model 501-D13, 501-D13A, 501-D13D, 501-D13E, 501-D13H engines
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Torquemeter Housing
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_60-21-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 60-21-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: ALLISON Model 501-D13 Series Engines Subject: Torquemeter Housing Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 11/09/1960 Make: Rolls-Royce Corporation Model: 501-D13 | 501-D13A | 501-D13D | 501-D13E | 501-D13H Product Type: Engine Product Subtype: Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 60-21-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 60-21-01 SUBJECT HEADING: ALLISON Model 501-D13 Series Engines ACTION: SUMMARY: DATES: Effective November 9, 1960. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 60-21-01 ALLISON: Amdt. 208 Part 507 Federal Register October 8, 1960. Applies to All Model 501-D13 Series Engines. Compliance required at next overhaul of engine, power section or torquemeter, whichever occurs first, after the effective date of this AD. Several cases of rubbing of the torquemeter housing by the torquemeter reference shaft have resulted in complete separation of the housing into two sections. To preclude such failures, a mid-bearing torquemeter assembly, P/N 6823900, identified by a 1/2-inch by 2 1/2-inch blue stripe on the forward bevel of the housing shall be installed. (Allison Commercial Engine Bulletin No. 72-113 covers the same subject.) This directive effective November 9, 1960. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_60-21-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 60-21-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: ALLISON Model 501-D13 Series Engines Subject: Torquemeter Housing Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 11/09/1960 Make: Rolls-Royce Corporation Model: 501-D13 | 501-D13A | 501-D13D | 501-D13E | 501-D13H 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: 60-21-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 60-21-01 SUBJECT HEADING: ALLISON Model 501-D13 Series Engines ACTION: SUMMARY: DATES: Effective November 9, 1960. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 60-21-01 ALLISON: Amdt. 208 Part 507 Federal Register October 8, 1960. Applies to All Model 501-D13 Series Engines. Compliance required at next overhaul of engine, power section or torquemeter, whichever occurs first, after the effective date of this AD. Several cases of rubbing of the torquemeter housing by the torquemeter reference shaft have resulted in complete separation of the housing into two sections. To preclude such failures, a mid-bearing torquemeter assembly, P/N 6823900, identified by a 1/2-inch by 2 1/2-inch blue stripe on the forward bevel of the housing shall be installed. (Allison Commercial Engine Bulletin No. 72-113 covers the same subject.) This directive effective November 9, 1960. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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