AD FAA-2009-1221

We are adopting a new airworthiness directive (AD) for The Boeing Company Model 767 airplanes. This AD requires installing new panel assemblies in the main equipment center or on the forward cargo compartment sidewall and removing certain relays from some panels in the main equipment center. This AD also requires revising the maintenance program to incorporate Airworthiness Limitations (AWLs) No. 28-AWL-27 and No. 28-AWL-28. This AD also includes an alternative location for the installation of the new panel assemblies for airplanes that have the optional water system drain plumbing and changing the interconnecting wiring between the P141 panel and the P36 and P37 panels. For airplanes with a deactivated center fuel tank, this AD also requires an alternative functional test for the left and right override/jettison pumps. We are issuing this AD to prevent possible sources of ignition in a fuel tank caused by electrical fault or uncommanded dry operation of the main tank boost pumps and center auxiliary tank override and jettison pumps. This AD was prompted by fuel system reviews conducted by the manufacturer. An ignition source in the fuel tank could result in a fire or an explosion and consequent loss of the airplane.