Icing is the most serious environmental problem that you as a pilot, can encounter. A layer of ice can build on the wings, windshield or pitot probe that is thick enough to significantly affect the performance of the aircraft. Because of its shape and location, the pitot tube is extremely susceptible to icing and on most aircraft the pitot tube is not visible in flight. Even a partially obstructed pitot probe can result in inaccurate airspeed measurement that may cause you to increase speed beyond the capability of the airframe or to lower speed below stall. A mere layer of frost on the wings can severely increase the stall speed and/or decrease the stall angle-of-attack. If you are unaware of the situation and collect ice during take off or landing, the results can be disastrous.

Pitot Check™ provides an indication of icing conditions. It also monitors pitot heater current to ensure that the pitot heater is working properly. With Pitot Check™ you are alerted if ice begins to form on the most critical piece of instrumentation on the aircraft, the pitot probe. Since ice forms there first, you also know when stall and handling characteristics of the airplane are suspect.

Pitot Check™ uses capacitance to differentiate between a clean sensor and one contaminated with ice or water. The fundamental applied principle is that water and ice have dielectric constant 80 times higher than air. Temperature is used to differentiate between ice and water. The sensor is located near the pitot probe and its mount is designed to have the same accretion properties as the pitot probe.

The ICE annouciator on the display lights when there is contamination on the ice sensor and the outside air temperature is below 40 F. Also included in the electronics are heater over and under current monitoring, heater self-test, temperature sensing, ice detector integrity monitoring and the display interface.