Airworthiness Directives; Bombardier Model DHC-8-102, -103, -106, -201, -202, -301, -311, and -315 Airplanes

The FAA is adopting a new airworthiness directive (AD) for certain Bombardier Model DHC-8-102, -103, -106, -201, -202, -301, -311, and-315 airplanes. This AD requires revising the airplane flight manual to include applicable procedures to follow when the flightcrew receives abnormal indications of airspeed, altitude, or vertical airspeed. This AD also requires modifying the static system. This AD is prompted by a report of a leak in the static pressure system, which could result in loss of the static systems and consequent erroneous data displayed on the pilot's flight instruments. We are issuing this AD to advise the flightcrew of applicable procedures in the event of abnormal indications of airspeed, altitude, or vertical airspeed; and to prevent leaks in the static system, which could result in the loss of critical flight information that could result in reduced controllability of the airplane or controlled flight into terrain.