AD 55-17-01
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Lockheed Aircraft Corporation | 1049-54 | LOCKHEED Models 49, 149, 649, 749, and 1049 Airplanes |
| aircraft | Lockheed Aircraft Corporation | 1049B-55 (Navy R7V-1) | LOCKHEED Models 49, 149, 649, 749, and 1049 Airplanes |
| aircraft | Lockheed Aircraft Corporation | 1049C-55 | LOCKHEED Models 49, 149, 649, 749, and 1049 Airplanes |
| aircraft | Lockheed Aircraft Corporation | 1049D-55 | LOCKHEED Models 49, 149, 649, 749, and 1049 Airplanes |
| aircraft | Lockheed Aircraft Corporation | 1049E-55 | LOCKHEED Models 49, 149, 649, 749, and 1049 Airplanes |
| aircraft | Lockheed Aircraft Corporation | 1049F-55 (USAF C-121C) | LOCKHEED Models 49, 149, 649, 749, and 1049 Airplanes |
| aircraft | Lockheed Aircraft Corporation | 1049G-82 | LOCKHEED Models 49, 149, 649, 749, and 1049 Airplanes |
| aircraft | Lockheed Aircraft Corporation | 149-46 | LOCKHEED Models 49, 149, 649, 749, and 1049 Airplanes |
| aircraft | Lockheed Aircraft Corporation | 49-46 | LOCKHEED Models 49, 149, 649, 749, and 1049 Airplanes |
| aircraft | Lockheed Aircraft Corporation | 649-79 | LOCKHEED Models 49, 149, 649, 749, and 1049 Airplanes |
Unsafe Condition
Failure of wing flap torque tube assembly due to defective bolt P/N AN 23-19, suspected caused by initial overtorque.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Inspect bolts P/N AN 23-19 on wing flap torque tubes to ensure proper installation and torque (10 to 20 inch-pounds). Replace overtorqued bolts and consider using P/N AN23-20 bolts or washers within specified limits if needed.
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Compliance Time
December 1, 1955, unless already accomplished
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Affected Aircraft
Lockheed Models 49, 149, 649, 749, and 1049 airplanes
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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