AD 74-10-01
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Piper Aircraft Inc. | PA-23-250 (Navy UO-1) | Airworthiness Directives; Piper Model PA-23-250 Airplanes |
Unsafe Condition
Cracks developing in the outboard flap hinges (part numbers 17103-04 and 17103-05) could cause asymmetric flap conditions.
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Required Actions
Inspect outboard flap hinges (part numbers 17103-04 and 17103-05) using a 10-power magnifying glass or equivalent method approved by the FAA. Clean hinges before inspection. Replace cracked hinges with unused parts of the same part numbers or FAA-approved equivalents before further flight. Compliance is not required if Piper Kits 760 861 (right) and 760 817 (left) are installed.
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Compliance Time
Within the next 25 hours in service after December 31, 1975, and every 100 hours thereafter. Compliance time may be increased upon FAA approval with substantiating data.
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Affected Aircraft
Piper Model PA-23-250 (Navy UO-1) airplanes with serial numbers 27-3050, 27-3154 to 27-7405330.
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Federal Register Abstract
Outboard Flap Hinge
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_74-10-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 74-10-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Piper Model PA-23-250 Airplanes Subject: Outboard Flap Hinge Status: Current Citation: This information is not available. Citation Publish Date: 12/30/1975 Effective Date: 12/31/1975 Make: Piper Aircraft Inc. Model: PA-23-250 (Navy UO-1) Product Type: Aircraft Product Subtype: Small Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: AIR-700: Compliance & Airworthiness Division Office of Primary Responsibility: AIR-720: Operational Safety Branch CFR Part Reference: Part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: 74-10-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2480 AD NUMBER: 74-10-01 SUBJECT HEADING: Airworthiness Directives; Piper Model PA-23-250 Airplanes ACTION: SUMMARY: DATES: Effective December 31, 1975. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 74-10-01 PIPER: Amendment 39-1830 as amended by Amendment 39-2480. Applies to model PA-23-250, Aircraft Serial Numbers 27-3050, 27-3154 to 27-7405330, certificated in all categories. Unless already accomplished within the last 75 hours in service, to prevent possible asymmetric flap conditions attributed to cracks developing in the outboard flap hinge, the following must be performed within the next 25 hours in service after the effective date of this airworthiness directive, and every 100 hours thereafter: 1. Using the hydraulic hand pump, lower the flaps to full-down position. 2. Clean outboard hinges, part numbers 17103-04 (left) and 17103-05 (right). Using a 10-power magnifying glass, inspect these parts (outboard flap hinges) for cracks. An equivalent inspection method approved by the Chief, Engineering and Manufacturing Branch, FAA, Eastern Region, may be used. 3. If cracks are found, replace, before further flight, any cracked part with unused hinges, part number 17103-04 (left) and/or 17103-05 (right) or equivalent parts approved by the Chief, Engineering and Manufacturing Branch, FAA, Eastern Region. Compliance with this AD is not required upon incorporation of Piper Kits 760 861 (right flap) and 760 817 (left flap) or equivalent parts approved by the Chief, Engineering and Manufacturing Branch, FAA, Eastern Region. Upon request with substantiating data submitted through an FAA maintenance inspector, the compliance time specified in this AD may be increased by the Chief, Engineering and Manufacturing Branch, FAA, Eastern Region. Service Bulletin 408B pertains to the same subject. Amendment 39-1830 was effective May 7, 1974. This amendment 39-2480 is effective December 31, 1975. FOOTER:
Document Text
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AD Final Rules - DRS_74-10-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 74-10-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Piper Model PA-23-250 Airplanes Subject: Outboard Flap Hinge Status: Current Citation: This information is not available. Citation Publish Date: 12/30/1975 Effective Date: 12/31/1975 Make: Piper Aircraft Inc. Model: PA-23-250 (Navy UO-1) 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: 74-10-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2480 AD NUMBER: 74-10-01 SUBJECT HEADING: Airworthiness Directives; Piper Model PA-23-250 Airplanes ACTION: SUMMARY: DATES: Effective December 31, 1975. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 74-10-01 PIPER: Amendment 39-1830 as amended by Amendment 39-2480. Applies to model PA-23-250, Aircraft Serial Numbers 27-3050, 27-3154 to 27-7405330, certificated in all categories. Unless already accomplished within the last 75 hours in service, to prevent possible asymmetric flap conditions attributed to cracks developing in the outboard flap hinge, the following must be performed within the next 25 hours in service after the effective date of this airworthiness directive, and every 100 hours thereafter: 1. Using the hydraulic hand pump, lower the flaps to full-down position. 2. Clean outboard hinges, part numbers 17103-04 (left) and 17103-05 (right). Using a 10-power magnifying glass, inspect these parts (outboard flap hinges) for cracks. An equivalent inspection method approved by the Chief, Engineering and Manufacturing Branch, FAA, Eastern Region, may be used. 3. If cracks are found, replace, before further flight, any cracked part with unused hinges, part number 17103-04 (left) and/or 17103-05 (right) or equivalent parts approved by the Chief, Engineering and Manufacturing Branch, FAA, Eastern Region. Compliance with this AD is not required upon incorporation of Piper Kits 760 861 (right flap) and 760 817 (left flap) or equivalent parts approved by the Chief, Engineering and Manufacturing Branch, FAA, Eastern Region. Upon request with substantiating data submitted through an FAA maintenance inspector, the compliance time specified in this AD may be increased by the Chief, Engineering and Manufacturing Branch, FAA, Eastern Region. Service Bulletin 408B pertains to the same subject. Amendment 39-1830 was effective May 7, 1974. This amendment 39-2480 is effective December 31, 1975. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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