July 4, 2012 - 5:59am

A recent Aviation Maintenance Alerts published by the FAA highlights a problem that should never, ever come up in aerospace: a design that allows mechanics to install something opposite the way intended. In this case, according to AC 43-16A No. 407, mechanics installed the elevators on a Piaggio P.180 Avanti upside down. After doing so, the mechanics were even able to rig the elevators according to the aircraft maintenance manual (AMM) instructions. Although installed upside down, the twin-turboprop was able to fly, and it did. According to the FAA’s Alerts, “During flight, this reversed elevator installation greatly influenced elevator trim authority—additionally causing the airplane yoke to be in a noticeably different longitudinal position.” The Alerts goes on to note that Piaggio has added a note to the AMM, warning mechanics about this potential problem. The FAA added, “A very simple way to ensure the correct elevator is installed on the proper side is to verify the location of the static wicks—they must be on the upper surface of the elevator.”