AD 55-08-04
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Piper Aircraft Inc. | PA-22 | Airworthiness Directives; Piper Model PA-22 Aircraft |
Unsafe Condition
The Hypass No. 48P6 ignition filters short and ground out the magnetos when subjected to temperatures equal to the engine accessory temperature after a series of takeoffs.
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Required Actions
Remove the Hypass No. 48P6 ignition filters from the magnetos and replace them with Piper No. 63149 (Lear) filters obtainable from the Piper Service Department.
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Compliance Time
as soon as possible but not later than July 1, 1955
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Affected Aircraft
Piper Model PA-22 Serial Numbers 22-1621 Through 22-1625, 22-1627, 22-1630, 22-1633, 22-1634, 22-1637.
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Federal Register Abstract
Ignition Filter Replacement
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_55-08-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 55-08-04 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Piper Model PA-22 Aircraft Subject: Ignition Filter Replacement Status: Current Citation: This information is not available. Citation Publish Date: 12/04/1956 Effective Date: Make: Piper Aircraft Inc. Model: PA-22 Product Type: Aircraft Product Subtype: Small Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: AIR-700: Compliance & Airworthiness Division Office of Primary Responsibility: AIR-720: Operational Safety Branch CFR Part Reference: Part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: 55-08-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 55-08-04 SUBJECT HEADING: Airworthiness Directives; Piper Model PA-22 Aircraft ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 55-08-04 PIPER: Applies to Model PA-22 Serial Numbers 22-1621 Through 22-1625, 22-1627, 22-1630, 22-1633, 22-1634, 22-1637. Compliance required as soon as possible but not later than July 1, 1955. The Hypass No. 48P6 ignition filters should be removed from the magnetos and replaced with magneto filter, Piper No. 63149 (Lear) obtainable from the Piper Service Department. It has been found that the Hypass No. 48P6 filters short and ground out the magnetos when subjected to a temperature which has been reported to be equal to the engine accessory temperature after a series of takeoffs have been performed. FOOTER:
Document Text
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AD Final Rules - DRS_55-08-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 55-08-04 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Piper Model PA-22 Aircraft Subject: Ignition Filter Replacement Status: Current Citation: This information is not available. Citation Publish Date: 12/04/1956 Effective Date: Make: Piper Aircraft Inc. Model: PA-22 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: 55-08-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 55-08-04 SUBJECT HEADING: Airworthiness Directives; Piper Model PA-22 Aircraft ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 55-08-04 PIPER: Applies to Model PA-22 Serial Numbers 22-1621 Through 22-1625, 22-1627, 22-1630, 22-1633, 22-1634, 22-1637. Compliance required as soon as possible but not later than July 1, 1955. The Hypass No. 48P6 ignition filters should be removed from the magnetos and replaced with magneto filter, Piper No. 63149 (Lear) obtainable from the Piper Service Department. It has been found that the Hypass No. 48P6 filters short and ground out the magnetos when subjected to a temperature which has been reported to be equal to the engine accessory temperature after a series of takeoffs have been performed. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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