AD 51-13-01
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Martin-Marietta Corporation | 202 | Martin Models 202 and 202A Series Aircraft |
| aircraft | Martin-Marietta Corporation | 202A | Martin Models 202 and 202A Series Aircraft |
Unsafe Condition
Cracks in wing top cover splice angles and wedge assemblies could lead to wing structural failure.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Inspect wing top cover splice angles using 2- to 6-power glass. Replace cracked top cover wedge assemblies with specified new parts. Reinstall outer wings with engines removed and shim gaps as specified. Perform torque check on attach angle bolts post-first flight. Replace attach angle bolts and spar web splice bolt every 12,000 flight hours.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Every other No. 3 inspection period, approximately 620 hours flight time, or 6 months, whichever occurs first (for most aircraft except serials 9125-9127, 9129-9131 which require every 170 hours flight time). Replacement actions must be completed by January 1, 1953 (most aircraft) or May 15, 1952 (serials 9125-9127, 9129-9131). Bolt replacements every 12,000 flight hours.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Martin-Marietta Corporation Models 202 and 202A Series Aircraft, excluding serial numbers 9125 through 9127 and 9129 through 9131 (except for section 2 which applies to those serials).
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Wing Top Cover Splice Angles
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_51-13-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 51-13-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Martin Models 202 and 202A Series Aircraft Subject: Wing Top Cover Splice Angles 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Make: Martin-Marietta Corporation Model: 202 | 202A Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 51-13-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 51-13-01 SUBJECT HEADING: Martin Models 202 and 202A Series Aircraft ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 51-13-01 MARTIN: Applies to All Models 202 and 202A Series Aircraft as Noted. Compliance required as indicated. 1. Applies to all Serial Numbers except 9125 through 9127 and 9129 through 9131. A. Compliance required every other No. 3 inspection period, approximately 620 hours flight time, or 6 months, whichever occurs first. (1) Inspect the wing top cover splice angles with 2- to 6-power glass (may be conducted with paint on). On Model 202 Series aircraft, except Serial Numbers 9149 and 9150, these angles are P/N U23435 through U23442 (wedge assemblies Nos. 2021A12633 and 2021A12624). On Model 202 aircraft, Serial Numbers 9149 and 9150, and on all Model 202A Series aircraft, these angles are P/N A12025, A12026, U29403, U29404, U29407, and U29408 (wedge assemblies Nos. 2021A12023 and 2021A12024). (2) If cracks are found, the top cover wedge assembly must be replaced as outlined in item B. (3) Continue the inspections outlined in item A. until the replacement action outlined in item B. is accomplished. B. Compliance required not later than January 1, 1953. (1) Replace all wing top cover wedge angles with new angles as follows: On Model 202 Series aircraft, except Serial Numbers 9149 and 9150, the new angles are P/N 202A3000068-1 and -2 through 202A3000071-1 and -2 (wedge assemblies Nos. 2021C12336-9 and -10). On Model 202A aircraft, Serial Numbers 9149 and 9150, and on all Model 202A Series aircraft, the new angles are P/N 202A3000072-1 and -2 through 202A3000074-1 and -2 (wedge assemblies Nos. 2021C12090-9 and -10). (2) At the time of wedge assembly replacement, the outer wings must be reinstalled with the engines removed, and the mating faces shimmed to a maximum permissible gap of 0.020 inch. The rear spar fitting must also be shimmed to a zero gap for approximately the upper half of its area. (3) Each airplane must have a torque check on the attach angle bolts immediately after the first flight after any outer wing installation. If the torque is within 15 percent of the installation torque, it is satisfactory. (4) After the new wedge angles are incorporated, the inspection outlined in item A. is no longer applicable to that airplane. 2. Applies to Serial Numbers 9125 through 9127 and 9129 through 9131. A. Compliance required every 170 hours flight time. Conduct the inspection outlined in above item 1.A. on angles P/N U23435 through U23442 (wedge assemblies Nos. 2021A12623 and 2021A12624) until cracks are found and/or the replacement action outlined in item B. below is accomplished. B. Compliance required not later than May 15, 1952. Replace all wing top cover angles with new angles P/N 202A3000068-1 and -2 through 202A3000071-1 and -2, wedge assemblies Nos. 2121C12336-9 and -10, and when accomplished, the inspections outlined in above item A. are no longer applicable to that airplane. 3. Applies to all Model 202 and 202A Series. A. Compliance required every 12,000 flight hours. Replace all wing top cover attach angle bolts and spar web splice bolt. (Martin 202/202A Service Bulletins Nos. 180, 184, and 187 cover this same subject.) FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_51-13-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 51-13-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Martin Models 202 and 202A Series Aircraft Subject: Wing Top Cover Splice Angles 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: 51-13-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 51-13-01 SUBJECT HEADING: Martin Models 202 and 202A Series Aircraft ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 51-13-01 MARTIN: Applies to All Models 202 and 202A Series Aircraft as Noted. Compliance required as indicated. 1. Applies to all Serial Numbers except 9125 through 9127 and 9129 through 9131. A. Compliance required every other No. 3 inspection period, approximately 620 hours flight time, or 6 months, whichever occurs first. (1) Inspect the wing top cover splice angles with 2- to 6-power glass (may be conducted with paint on). On Model 202 Series aircraft, except Serial Numbers 9149 and 9150, these angles are P/N U23435 through U23442 (wedge assemblies Nos. 2021A12633 and 2021A12624). On Model 202 aircraft, Serial Numbers 9149 and 9150, and on all Model 202A Series aircraft, these angles are P/N A12025, A12026, U29403, U29404, U29407, and U29408 (wedge assemblies Nos. 2021A12023 and 2021A12024). (2) If cracks are found, the top cover wedge assembly must be replaced as outlined in item B. (3) Continue the inspections outlined in item A. until the replacement action outlined in item B. is accomplished. B. Compliance required not later than January 1, 1953. (1) Replace all wing top cover wedge angles with new angles as follows: On Model 202 Series aircraft, except Serial Numbers 9149 and 9150, the new angles are P/N 202A3000068-1 and -2 through 202A3000071-1 and -2 (wedge assemblies Nos. 2021C12336-9 and -10). On Model 202A aircraft, Serial Numbers 9149 and 9150, and on all Model 202A Series aircraft, the new angles are P/N 202A3000072-1 and -2 through 202A3000074-1 and -2 (wedge assemblies Nos. 2021C12090-9 and -10). (2) At the time of wedge assembly replacement, the outer wings must be reinstalled with the engines removed, and the mating faces shimmed to a maximum permissible gap of 0.020 inch. The rear spar fitting must also be shimmed to a zero gap for approximately the upper half of its area. (3) Each airplane must have a torque check on the attach angle bolts immediately after the first flight after any outer wing installation. If the torque is within 15 percent of the installation torque, it is satisfactory. (4) After the new wedge angles are incorporated, the inspection outlined in item A. is no longer applicable to that airplane. 2. Applies to Serial Numbers 9125 through 9127 and 9129 through 9131. A. Compliance required every 170 hours flight time. Conduct the inspection outlined in above item 1.A. on angles P/N U23435 through U23442 (wedge assemblies Nos. 2021A12623 and 2021A12624) until cracks are found and/or the replacement action outlined in item B. below is accomplished. B. Compliance required not later than May 15, 1952. Replace all wing top cover angles with new angles P/N 202A3000068-1 and -2 through 202A3000071-1 and -2, wedge assemblies Nos. 2121C12336-9 and -10, and when accomplished, the inspections outlined in above item A. are no longer applicable to that airplane. 3. Applies to all Model 202 and 202A Series. A. Compliance required every 12,000 flight hours. Replace all wing top cover attach angle bolts and spar web splice bolt. (Martin 202/202A Service Bulletins Nos. 180, 184, and 187 cover this same subject.) 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.