SR22
Flight Crew Instrument; Flight Crew Private
Flight Crew Last 90 Days 25; Flight Crew Total 480; Flight Crew Type 480
Training / Qualification; Situational Awareness
Deviation / Discrepancy - Procedural Published Material / Policy; Inflight Event / Encounter Weather / Turbulence
Air Traffic Control Issued New Clearance; Air Traffic Control Provided Assistance; Flight Crew Overcame Equipment Problem
Weather; Procedure
Before and during an emergency descent from icing condition and during minor approved deviations for storm cells; PFD was showing slowing airspeed. OAT was -12C. PFD continued to show slower; then stalling airspeed. Speed protection audible callout began. Checked engine and icing; but neither appeared to be a problem. There was no apparent icing on wings. I asked ATC for lower to get below the freezing point and was cleared in steps to 13;000 FT. I clicked off the autopilot for descent to have a better feel for airplane handling. On descent; I clicked on the pitot heat; which shortly thereafter brought back correct airspeed indications. Continued on course and assigned altitude.
SR22 pilot making an emergency descent out of icing conditions noted decreasing airspeed indications followed by an airspeed audible warning. Pilot turned on pitot heat which rectified the airspeed indication problem.