Blocked pitot-static monitor

A method of monitoring a pitot-static avionics system for blockages, the method comprising:

• calculating a first aircraft movement rate as a function of a first pressure sensed using the pitot-static system;
• calculating a second aircraft movement rate as a function of a second pressure sensed using the pitot-static system;
• calculating a reference aircraft movement rate;
• comparing the calculated first aircraft movement rate, the calculated second aircraft movement rate and the calculated reference aircraft movement rate;
• and
• determining whether a blockage exists in the pitot-static system based upon the comparison.

An avionics system comprising:

• a pitot-static system including at least one pitot tube and at least one static port, the pitot-static system providing an output indicative of a pressure sensed by the pitot-static system;
• a first aircraft movement rate calculator coupled to the pitot-static system and adapted to calculate a first aircraft movement rate as a function of the pressure sensed by the pitot-static system;
• a navigation system providing a navigation system output;
• an aircraft reference movement rate calculator coupled to the navigation system and adapted to calculate a reference movement rate of the aircraft as a function of the navigation system output;
• comparison circuitry adapted to compare the calculated first aircraft movement rate to the calculated reference movement rate;
• and
• pitot-static blockage determination circuitry coupled to the comparison circuitry and adapted to determine whether a blockage exists in at least one of a pitot tube and a static port as a function of the comparison.