Summary
This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Lockheed Model L-1011-385- 1 series airplanes. This proposal would require modification of the power drive units and the lower drive sprocket assemblies of the galley lift system. This proposal is prompted by a report indicating that, due to fatigue cracking, the primary and secondary drive shafts of the galley lift failed and caused the galley lift to drop to the lower level, injuring a flight attendant. The actions specified by the proposed AD are intended to prevent such fatigue cracking of the primary and secondary drive shafts, which could result in complete fracturing of the secondary shaft; such fracturing could allow the galley lift to drop to the bottom of the shaft, and could result in possible injury to crewmembers.