AD 68-21-03
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Piper Aircraft Inc. | PA-23-250 (Navy UO-1) | Airworthiness Directives; Piper Model PA-23-250 and PA-E23-250 Aircraft |
| aircraft | Piper Aircraft Inc. | PA-E23-250 | Airworthiness Directives; Piper Model PA-23-250 and PA-E23-250 Aircraft |
Unsafe Condition
Failures of the exhaust tailpipe assemblies, specifically AiResearch P/N 286-P23-060-5 and P/N 286-P23-060-9, due to cracks or deformation and insufficient clearance between tailpipes and firewalls/cowl flaps.
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Required Actions
Visually inspect both left and right engine tailpipes for cracks or deformation; retire and replace affected assemblies. Inspect tailpipe clearance against firewalls and cowl flaps per AiResearch Service Bulletin No. 14.1.8; install Kit P/N 301-P23-063 if clearance is insufficient.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
within 10 hours of aircraft operations after the effective date of this Airworthiness Directive, unless previously accomplished
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Affected Aircraft
Piper Model PA-23-250 and PA-E23-250 Aircraft Serial Nos. 27-2505 through 27-3858 with AiResearch Turbosupercharged Lycoming IO-540-J4A5 or IO-540-C4B5 engines installed per STC SA909WE, SA978WE, or Piper Drawing No. 32016
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Exhaust Tailpipe Assemblies
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_68-21-03.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 68-21-03 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Piper Model PA-23-250 and PA-E23-250 Aircraft Subject: Exhaust Tailpipe Assemblies Status: Current Citation: This information is not available. Citation Publish Date: 10/11/1968 Effective Date: 10/28/1968 Make: Piper Aircraft Inc. Model: PA-23-250 (Navy UO-1) | PA-E23-250 Product Type: Aircraft Product Subtype: Small Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: AIR-700: Compliance & Airworthiness Division Office of Primary Responsibility: AIR-720: Operational Safety Branch CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 68-21-03 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-667 AD NUMBER: 68-21-03 SUBJECT HEADING: Airworthiness Directives; Piper Model PA-23-250 and PA-E23-250 Aircraft ACTION: SUMMARY: DATES: Effective October 28, 1968. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 68-21-03 PIPER: Amendment 39-667. Applies to Model PA-23-250 and PA-E23-250 Aircraft Serial Nos. 27-2505 through 27-3858 that Incorporate AiResearch Turbosupercharged Lycoming IO-540-J4A5 or IO-540-C4B5 Engines Installed in accordance with Supplemental Type Certificate No. SA909WE or SA978WE, or in accordance with Piper Aircraft Corporation Drawing No. 32016. Compliance required within 10 hours of aircraft operations after the effective date of this Airworthiness Directive, unless previously accomplished. To preclude failures of the exhaust tailpipe assemblies, AiResearch P/N 286-P23-060-5 and P/N 286-P23-060-9: (a) Visually inspect both the left and right hand engine tailpipes for cracks or deformation. If a crack or deformation is found in either tailpipe, retire the affected tailpipe assembly and replace with a new tailpipe assembly of the same part number. (b) Visually inspect both the left and right hand engine tailpipes for sufficient clearance between the tailpipes and the firewalls and between the tailpipes and the cowl flaps in accordance with AiResearch Aviation Service Company Service Bulletin No. 14.1.8 dated April 25, 1968, or later FAA approved revisions. If sufficient clearance does not exist, install AiResearch Kit P/N 301-P23-063 and adjust for sufficient clearance in accordance with the above service bulletin. This amendment becomes effective October 28, 1968. FOOTER:
Document Text
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AD Final Rules - DRS_68-21-03.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 68-21-03 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Piper Model PA-23-250 and PA-E23-250 Aircraft Subject: Exhaust Tailpipe Assemblies Status: Current Citation: This information is not available. Citation Publish Date: 10/11/1968 Effective Date: 10/28/1968 Make: Piper Aircraft Inc. Model: PA-23-250 (Navy UO-1) | PA-E23-250 Product Type: Aircraft Product Subtype: Small Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: AIR-700: Compliance & Airworthiness Division Office of Primary Responsibility: AIR-720: Operational Safety Branch CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 68-21-03 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-667 AD NUMBER: 68-21-03 SUBJECT HEADING: Airworthiness Directives; Piper Model PA-23-250 and PA-E23-250 Aircraft ACTION: SUMMARY: DATES: Effective October 28, 1968. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 68-21-03 PIPER: Amendment 39-667. Applies to Model PA-23-250 and PA-E23-250 Aircraft Serial Nos. 27-2505 through 27-3858 that Incorporate AiResearch Turbosupercharged Lycoming IO-540-J4A5 or IO-540-C4B5 Engines Installed in accordance with Supplemental Type Certificate No. SA909WE or SA978WE, or in accordance with Piper Aircraft Corporation Drawing No. 32016. Compliance required within 10 hours of aircraft operations after the effective date of this Airworthiness Directive, unless previously accomplished. To preclude failures of the exhaust tailpipe assemblies, AiResearch P/N 286-P23-060-5 and P/N 286-P23-060-9: (a) Visually inspect both the left and right hand engine tailpipes for cracks or deformation. If a crack or deformation is found in either tailpipe, retire the affected tailpipe assembly and replace with a new tailpipe assembly of the same part number. (b) Visually inspect both the left and right hand engine tailpipes for sufficient clearance between the tailpipes and the firewalls and between the tailpipes and the cowl flaps in accordance with AiResearch Aviation Service Company Service Bulletin No. 14.1.8 dated April 25, 1968, or later FAA approved revisions. If sufficient clearance does not exist, install AiResearch Kit P/N 301-P23-063 and adjust for sufficient clearance in accordance with the above service bulletin. This amendment becomes effective October 28, 1968. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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