Summary
We propose to adopt an airworthiness directive (AD) for all The Boeing Company Model 757-200 series airplanes. This proposed AD was prompted by reports of uncommanded movement of the captain's and first officer's seats. This proposed AD would require, for the captain's and first officer's seats, repetitive horizontal actuator identifications, repetitive checks of the horizontal movement system (HMS), a detailed inspection of the HMS, as applicable, and applicable on-condition actions. This proposed AD would also require a general visual inspection to determine seat part numbers of the captain's and first officer's seats, a cable adjustment check on seats with certain seat part numbers, and applicable on-condition actions. We are proposing this AD to address the unsafe condition on these products.