AD 61-24-04
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Lockheed Aircraft Corporation | 1049-54 | LOCKHEED Models 049, 149, 649, 749, and 1049 Series Aircraft |
| aircraft | Lockheed Aircraft Corporation | 1049B-55 (Navy R7V-1) | LOCKHEED Models 049, 149, 649, 749, and 1049 Series Aircraft |
| aircraft | Lockheed Aircraft Corporation | 1049C-55 | LOCKHEED Models 049, 149, 649, 749, and 1049 Series Aircraft |
| aircraft | Lockheed Aircraft Corporation | 1049D-55 | LOCKHEED Models 049, 149, 649, 749, and 1049 Series Aircraft |
| aircraft | Lockheed Aircraft Corporation | 1049E-55 | LOCKHEED Models 049, 149, 649, 749, and 1049 Series Aircraft |
| aircraft | Lockheed Aircraft Corporation | 1049F-55 (USAF C-121C) | LOCKHEED Models 049, 149, 649, 749, and 1049 Series Aircraft |
| aircraft | Lockheed Aircraft Corporation | 1049G-82 | LOCKHEED Models 049, 149, 649, 749, and 1049 Series Aircraft |
| aircraft | Lockheed Aircraft Corporation | 1049H-82 | LOCKHEED Models 049, 149, 649, 749, and 1049 Series Aircraft |
| aircraft | Lockheed Aircraft Corporation | 149-46 | LOCKHEED Models 049, 149, 649, 749, and 1049 Series Aircraft |
| aircraft | Lockheed Aircraft Corporation | 49-46 | LOCKHEED Models 049, 149, 649, 749, and 1049 Series Aircraft |
| aircraft | Lockheed Aircraft Corporation | 649-79 | LOCKHEED Models 049, 149, 649, 749, and 1049 Series Aircraft |
| aircraft | Lockheed Aircraft Corporation | 649A-79 | LOCKHEED Models 049, 149, 649, 749, and 1049 Series Aircraft |
| aircraft | Lockheed Aircraft Corporation | 749-79 | LOCKHEED Models 049, 149, 649, 749, and 1049 Series Aircraft |
| aircraft | Lockheed Aircraft Corporation | 749A-79 | LOCKHEED Models 049, 149, 649, 749, and 1049 Series Aircraft |
Unsafe Condition
Cracking in the horizontal stabilizer rear spar-to-fuselage attachment due to fatigue.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Inspect the rear spar web (P/N 271488-4) for cracks in the 0.38 inch radius adjacent to the stabilizer-to-fuselage fitting on both sides. Repair cracks prior to further flight per Lockheed Service Letter FS/250615 or FAA-approved equivalent. Discontinue inspections after implementing the specified repair or reinforcement.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within 400 hours' time in service after effective date (December 14, 1961), unless already accomplished within the last 4,300 hours' time in service and at intervals of 4,700 hours' time in service.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Lockheed Models 049, 149, 649, 749, and 1049 Series Aircraft with 25,000 or more hours' time in service.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Horizontal Stabilizer Rear Spar
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_61-24-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 61-24-04 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: LOCKHEED Models 049, 149, 649, 749, and 1049 Series Aircraft Subject: Horizontal Stabilizer Rear Spar Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 12/14/1961 Make: Lockheed Aircraft Corporation Model: 1049-54 | 1049B-55 (Navy R7V-1) | 1049C-55 | 1049D-55 | 1049E-55 | 1049F-55 (USAF C-121C) | 1049G-82...Show more 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: 61-24-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 61-24-04 SUBJECT HEADING: LOCKHEED Models 049, 149, 649, 749, and 1049 Series Aircraft ACTION: SUMMARY: DATES: Effective December 14, 1961. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 61-24-04 LOCKHEED: Amdt. 367 Part 507 Federal Register November 14, 1961. Applies to All Models 049, 149, 649, 749, and 1049 Series Aircraft Having 25,000 Or More Hours' Time In Service. Compliance required as indicated. As a result of reports of numerous cases of cracking in the horizontal stabilizer rear spar- to-fuselage attachment, the following inspections must be accomplished within the next 400 hours' time in service after effective date of this AD, unless already accomplished within the last 4,300 hours' time in service and at intervals of 4,700 hours' time in service. Inspect the rear spar web (P/N 271488-4) for cracks in the 0.38 inch radius adjacent to the stabilizer-to-fuselage fitting on both the left and right sides of the airplane. If cracks are found, they must be repaired prior to further flight in accordance with Lockheed Service Letter FS/250615, or FAA approved equivalent. The above inspection may be discontinued upon incorporation of the repair or reinforcement provisions of the Lockheed Service Letter, or FAA approved equivalent. Upon request of the operator, an FAA maintenance inspector, subject to prior approval of the Chief, Engineering and Manufacturing Branch, FAA Western Region, may adjust the repetitive inspection intervals specified in this AD to permit compliance at an established inspection period of the operator if the request contains substantiating data to justify the increase for such operator. This directive effective December 14, 1961. FOOTER:
Document Text
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AD Final Rules - DRS_61-24-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 61-24-04 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: LOCKHEED Models 049, 149, 649, 749, and 1049 Series Aircraft Subject: Horizontal Stabilizer Rear Spar Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 12/14/1961 Make: Lockheed Aircraft Corporation Model: 1049-54 | 1049B-55 (Navy R7V-1) | 1049C-55 | 1049D-55 | 1049E-55 | 1049F-55 (USAF C-121C) | 1049G-82...Show more 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: 61-24-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 61-24-04 SUBJECT HEADING: LOCKHEED Models 049, 149, 649, 749, and 1049 Series Aircraft ACTION: SUMMARY: DATES: Effective December 14, 1961. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 61-24-04 LOCKHEED: Amdt. 367 Part 507 Federal Register November 14, 1961. Applies to All Models 049, 149, 649, 749, and 1049 Series Aircraft Having 25,000 Or More Hours' Time In Service. Compliance required as indicated. As a result of reports of numerous cases of cracking in the horizontal stabilizer rear spar- to-fuselage attachment, the following inspections must be accomplished within the next 400 hours' time in service after effective date of this AD, unless already accomplished within the last 4,300 hours' time in service and at intervals of 4,700 hours' time in service. Inspect the rear spar web (P/N 271488-4) for cracks in the 0.38 inch radius adjacent to the stabilizer-to-fuselage fitting on both the left and right sides of the airplane. If cracks are found, they must be repaired prior to further flight in accordance with Lockheed Service Letter FS/250615, or FAA approved equivalent. The above inspection may be discontinued upon incorporation of the repair or reinforcement provisions of the Lockheed Service Letter, or FAA approved equivalent. Upon request of the operator, an FAA maintenance inspector, subject to prior approval of the Chief, Engineering and Manufacturing Branch, FAA Western Region, may adjust the repetitive inspection intervals specified in this AD to permit compliance at an established inspection period of the operator if the request contains substantiating data to justify the increase for such operator. This directive effective December 14, 1961. FOOTER:
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