Summary: We are adopting a new airworthiness directive (AD) for certain Lockheed Martin Corporation/Lockheed Martin Aeronautics Company Model L-1011-385-1, L-1011-385-1-14, L-1011-385-1-15, and L-1011-385-3 airplanes. This AD was prompted by results from a damage tolerance analysis conducted by the manufacturer indicating that fatigue cracking could occur in wing rear spar and upper surface zones. This AD requires repetitive inspections for cracking of the wing rear spar and upper surface zones, and repair if necessary. We are issuing this AD to detect and correct such fatigue cracking, which could result in cracking that grows large enough to reduce the wing strength below certificated requirements and possibly cause fracture of the rear spar, resulting in extensive damage to the wing and possible fuel leaks.(Source / PDF)
