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 |
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.
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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.
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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.
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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