AD 68-05-03
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| engine | Pratt & Whitney Canada Corp. | PT6A-20 | UNITED AIRCRAFT of CANADA, LIMITED Models PT6A-6B and PT6A-20 Engines |
| engine | Pratt & Whitney Canada Corp. | PT6A-6B | UNITED AIRCRAFT of CANADA, LIMITED Models PT6A-6B and PT6A-20 Engines |
Unsafe Condition
Failure of the propeller to reverse or immediate reversing upon selection of reverse mode due to insufficient wall thickness in teleflex reversing control cable terminals P/N's 3010175 and 30101495.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Install a placard prohibiting propeller reverse use, X-ray or physically inspect terminals for minimum 0.08-inch wall thickness, and replace terminals below minimums with approved parts marked DH.
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Compliance Time
prior to further flight for (a), within the next 25 hours' time in service after February 28, 1968 for (b), (c), and (d) where applicable
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Affected Aircraft
Pratt & Whitney Canada Corp. Models PT6A-6B and PT6A-20 Engines
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Reverse Mode
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_68-05-03.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 68-05-03 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: UNITED AIRCRAFT of CANADA, LIMITED Models PT6A-6B and PT6A-20 Engines Subject: Reverse Mode Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 02/28/1968 Make: Pratt & Whitney Canada Corp. Model: PT6A-20 | PT6A-6B Product Type: Engine Product Subtype: Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 68-05-03 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-558 AD NUMBER: 68-05-03 SUBJECT HEADING: UNITED AIRCRAFT of CANADA, LIMITED Models PT6A-6B and PT6A-20 Engines ACTION: SUMMARY: DATES: Effective February 28, 1968. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 68-05-03 UNITED AIRCRAFT of CANADA, LIMITED: Amdt. 39-558. Applies to Models PT6A-6B and PT6A-20 Turboprop Engines. Compliance, unless already accomplished, with (a) required prior to further flight and with (b) or (c) and where applicable (d) within the next 25 hours' time in service after the effective date of this AD. To preclude either failure of the propeller to reverse or immediate reversing upon selection of reverse mode, the selection of propeller reversing is prohibited until the following inspections or replacements have been accomplished. (a) Install a placard in the cockpit in full view of the pilot that reads: "Do not Use Propeller Reverse". (b) X-ray teleflex reversing control cable terminals P/N's 3010175 and 30101495 to determine that a minimum of 0.08-inch wall thickness exists between cable counterbore and shoulder of threaded yoke arm spindle undercut. Reject terminals with thickness below 0.08 inch. (c) If X-ray is unavailable, disassemble the terminals and physically inspect in accordance with the instructions in United Aircraft of Canada, Ltd., Special Inspection No. 68-1 or an equivalent approved by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region. (d) Replace terminals found below minimums with the same part number known to have sufficient wall thickness. (Spare terminals with walls verified to be in excess of 0.08-inch thick are identified with the letters DH within a circle marked on the hex of the coupling.) (The information in this AD is similar to that contained in Canadian Department of Transport AD No. DF-PT-68-2 issued telegraphically on February 6, 1968.) This amendment becomes effective February 28, 1968. FOOTER:
Document Text
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AD Final Rules - DRS_68-05-03.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 68-05-03 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: UNITED AIRCRAFT of CANADA, LIMITED Models PT6A-6B and PT6A-20 Engines Subject: Reverse Mode Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 02/28/1968 Make: Pratt & Whitney Canada Corp. Model: PT6A-20 | PT6A-6B 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: 68-05-03 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-558 AD NUMBER: 68-05-03 SUBJECT HEADING: UNITED AIRCRAFT of CANADA, LIMITED Models PT6A-6B and PT6A-20 Engines ACTION: SUMMARY: DATES: Effective February 28, 1968. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 68-05-03 UNITED AIRCRAFT of CANADA, LIMITED: Amdt. 39-558. Applies to Models PT6A-6B and PT6A-20 Turboprop Engines. Compliance, unless already accomplished, with (a) required prior to further flight and with (b) or (c) and where applicable (d) within the next 25 hours' time in service after the effective date of this AD. To preclude either failure of the propeller to reverse or immediate reversing upon selection of reverse mode, the selection of propeller reversing is prohibited until the following inspections or replacements have been accomplished. (a) Install a placard in the cockpit in full view of the pilot that reads: "Do not Use Propeller Reverse". (b) X-ray teleflex reversing control cable terminals P/N's 3010175 and 30101495 to determine that a minimum of 0.08-inch wall thickness exists between cable counterbore and shoulder of threaded yoke arm spindle undercut. Reject terminals with thickness below 0.08 inch. (c) If X-ray is unavailable, disassemble the terminals and physically inspect in accordance with the instructions in United Aircraft of Canada, Ltd., Special Inspection No. 68-1 or an equivalent approved by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region. (d) Replace terminals found below minimums with the same part number known to have sufficient wall thickness. (Spare terminals with walls verified to be in excess of 0.08-inch thick are identified with the letters DH within a circle marked on the hex of the coupling.) (The information in this AD is similar to that contained in Canadian Department of Transport AD No. DF-PT-68-2 issued telegraphically on February 6, 1968.) This amendment becomes effective February 28, 1968. FOOTER:
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Retrieved: Apr 8, 2026
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