FAA–2012–0720 Loss of displayed airspeed

We are adopting a new airworthiness directive (AD) for certain Cessna Aircraft Company Model 750 airplanes. This AD was prompted by reports of loss of displayed airspeed. This AD requires inspecting certain logic modules to determine if certain cabin altitude/pitot static heater module assemblies are installed and replacing those assemblies with a new assembly; and revising the Non-Normal Procedures Section of the airplane flight manual (AFM) to include procedures for resetting the pitot switch in the event of pitot heater failure and for total loss of airspeed indication. We are issuing this AD to prevent the loss of all displayed airspeed, which could result in reduced ability to control the airplane.