AD 74-12-10
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Mitsubishi Heavy Industries, Ltd. | YS-11 | Airworthiness Directives; NIHON AEROPLANE MANUFACTURING COMPANY LIMITED Model YS-11/11A Series Airplanes |
| aircraft | Mitsubishi Heavy Industries, Ltd. | YS-11A-200 | Airworthiness Directives; NIHON AEROPLANE MANUFACTURING COMPANY LIMITED Model YS-11/11A Series Airplanes |
| aircraft | Mitsubishi Heavy Industries, Ltd. | YS-11A-300 | Airworthiness Directives; NIHON AEROPLANE MANUFACTURING COMPANY LIMITED Model YS-11/11A Series Airplanes |
| aircraft | Mitsubishi Heavy Industries, Ltd. | YS-11A-500 | Airworthiness Directives; NIHON AEROPLANE MANUFACTURING COMPANY LIMITED Model YS-11/11A Series Airplanes |
| aircraft | Mitsubishi Heavy Industries, Ltd. | YS-11A-600 | Airworthiness Directives; NIHON AEROPLANE MANUFACTURING COMPANY LIMITED Model YS-11/11A Series Airplanes |
Unsafe Condition
Possible malfunction in the auxiliary power unit (APU) wiring harness that could result in a fire.
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Required Actions
Inspect and modify the installation of the APU electrical wiring harnesses in accordance with Japan Civil Aviation Bureau approved NAMC YS-11 Service Bulletin No. A49-13 or an equivalent approved by the Chief, Engineering and Manufacturing District Office, FAA, Pacific-Asia Region.
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Compliance Time
within the next 25 hours' time in service after the effective date of this AD unless already accomplished
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Affected Aircraft
NAMC Model YS-11/11A series airplanes with serial numbers 2050 through 2053, 2056, 2057, 2061, 2062, 2072, 2073, 2075, 2077, 2079, 2084, 2086 through 2089, 2091, 2100, 2118 through 2123, 2126, 2128, 2129, 2132, 2140, 2148, 2159, 2169, 2172, 2173, and 2179 through 2181 equipped with AiResearch APU's.
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Federal Register Abstract
Auxiliary Power Unit
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_74-12-10.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 74-12-10 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; NIHON AEROPLANE MANUFACTURING COMPANY LIMITED Model YS-11/11A Series Airplanes Subject: Auxiliary Power Unit Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 06/12/1974 Make: Mitsubishi Heavy Industries, Ltd. Model: YS-11 | YS-11A-200 | YS-11A-300 | YS-11A-500 | YS-11A-600 Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 74-12-10 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1866 AD NUMBER: 74-12-10 SUBJECT HEADING: Airworthiness Directives; NIHON AEROPLANE MANUFACTURING COMPANY LIMITED Model YS-11/11A Series Airplanes ACTION: SUMMARY: DATES: Effective June 12, 1974. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 74-12-10 NIHON AEROPLANE MANUFACTURING COMPANY LIMITED: Amendment 39-1866. Applies to NAMC Model YS-11/11A series airplanes (S/N's 2050 through 2053, 2056, 2057, 2061, 2062, 2072, 2073, 2075, 2077, 2079, 2084, 2086 through 2089, 2091, 2100, 2118 through 2123, 2126, 2128, 2129, 2132, 2140, 2148, 2159, 2169, 2172, 2173, and 2179 through 2181) equipped with AiResearch APU's. Compliance required within the next 25 hours' time in service after the effective date of this AD unless already accomplished. To prevent possible malfunction in the auxiliary power unit (APU) wiring harness that could result in a fire, inspect and modify the installation of the APU electrical wiring harnesses in accordance with the Japan Civil Aviation Bureau approved NAMC YS-11 Service Bulletin No. A49-13, dated February 25, 1974 or an equivalent approved by the Chief, Engineering and Manufacturing District Office, FAA, Pacific-Asia Region. This amendment becomes effective June 12, 1974. FOOTER:
Document Text
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AD Final Rules - DRS_74-12-10.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 74-12-10 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; NIHON AEROPLANE MANUFACTURING COMPANY LIMITED Model YS-11/11A Series Airplanes Subject: Auxiliary Power Unit Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 06/12/1974 Make: Mitsubishi Heavy Industries, Ltd. Model: YS-11 | YS-11A-200 | YS-11A-300 | YS-11A-500 | YS-11A-600 Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 74-12-10 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1866 AD NUMBER: 74-12-10 SUBJECT HEADING: Airworthiness Directives; NIHON AEROPLANE MANUFACTURING COMPANY LIMITED Model YS-11/11A Series Airplanes ACTION: SUMMARY: DATES: Effective June 12, 1974. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 74-12-10 NIHON AEROPLANE MANUFACTURING COMPANY LIMITED: Amendment 39-1866. Applies to NAMC Model YS-11/11A series airplanes (S/N's 2050 through 2053, 2056, 2057, 2061, 2062, 2072, 2073, 2075, 2077, 2079, 2084, 2086 through 2089, 2091, 2100, 2118 through 2123, 2126, 2128, 2129, 2132, 2140, 2148, 2159, 2169, 2172, 2173, and 2179 through 2181) equipped with AiResearch APU's. Compliance required within the next 25 hours' time in service after the effective date of this AD unless already accomplished. To prevent possible malfunction in the auxiliary power unit (APU) wiring harness that could result in a fire, inspect and modify the installation of the APU electrical wiring harnesses in accordance with the Japan Civil Aviation Bureau approved NAMC YS-11 Service Bulletin No. A49-13, dated February 25, 1974 or an equivalent approved by the Chief, Engineering and Manufacturing District Office, FAA, Pacific-Asia Region. This amendment becomes effective June 12, 1974. FOOTER:
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Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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