AD 51-25-02
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Martin-Marietta Corporation | 202 | Martin Models 202 and 202A Airplanes |
| aircraft | Martin-Marietta Corporation | 202A | Martin Models 202 and 202A Airplanes |
Unsafe Condition
Inadvertent shorting between the "MAIN" and "CONTROL" terminals of the D7231-125 inverter remote reset circuit breaker.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Install a cover over the D7231-125 inverter remote reset circuit breaker terminals. Compliance must follow Martin Service Instruction Letter No. 8 dated September 10, 1951, or an equivalent method.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
January 1, 1952
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Affected Aircraft
Martin-Marietta Corporation Models 202 and 202A Airplanes, all serial numbers.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Circuit Breaker Cover
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_51-25-02.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 51-25-02 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Martin Models 202 and 202A Airplanes Subject: Circuit Breaker Cover Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Martin-Marietta Corporation Model: 202 | 202A Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 51-25-02 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 51-25-02 SUBJECT HEADING: Martin Models 202 and 202A Airplanes ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 51-25-02 MARTIN: Applies to All Models 202 and 202A Airplanes. Compliance required by January 1, 1952. Install cover over D7231-125 inverter remote reset circuit breaker terminals to prevent inadvertent shorting between "MAIN" and "CONTROL" terminals. Compliance may be made in same manner or equivalent to Martin Service Instruction Letter No. 8 dated September 10, 1951. This supersedes the first item in AD 51-11-01 requiring the redesign of the d.c. input circuit breaker mounting. FOOTER:
Document Text
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AD Final Rules - DRS_51-25-02.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 51-25-02 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Martin Models 202 and 202A Airplanes Subject: Circuit Breaker Cover Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Martin-Marietta Corporation Model: 202 | 202A 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: 51-25-02 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 51-25-02 SUBJECT HEADING: Martin Models 202 and 202A Airplanes ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 51-25-02 MARTIN: Applies to All Models 202 and 202A Airplanes. Compliance required by January 1, 1952. Install cover over D7231-125 inverter remote reset circuit breaker terminals to prevent inadvertent shorting between "MAIN" and "CONTROL" terminals. Compliance may be made in same manner or equivalent to Martin Service Instruction Letter No. 8 dated September 10, 1951. This supersedes the first item in AD 51-11-01 requiring the redesign of the d.c. input circuit breaker mounting. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
This site is not affiliated with or endorsed by the FAA. Always verify with official sources.
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