Narrative:

A cold front was forecast to move through arizona and colorado during our flight from gjt to phx. The first leg of this scheduled trip (phx-gjt) was completely free of inclement WX en route. Our flight was on the ground approximately 10 mins in gjt and it took approximately 25 mins to go from gjt to the 80 NM north of tbc. Therefore, from the time we first passed the area of freezing rain on our way to gjt to the time we actually encountered it was only about 1 hour. We first encountered what seemed to be light to moderate mixed icing at FL220. (Our aircraft is approved for flight into known icing, complete with heated windshield, leading edge boots, heated propellers, and pneumatically heated PT6-a engine inlet lip heat.) however, after a short time, the heated windshield began icing up, as well as the engine inlet lip area! The inlet lip heat is heated to approximately 720 degrees C by ducting exhaust air through ducting under the lip. We noted the outside air temperature of 0 degrees C, and were cleared to 15000 ft MSL. The temperature (0 degrees C) and icing continued all the way down to 11000 ft MSL. Moderate turbulence occurred throughout the flight which lasted 2 hours 25 mins with a diversion to prc for fuel. A postflt inspection of the aircraft revealed large pits in the fuselage paint adjacent the propellers and propeller paint nicked off from the ice. All the literature on freezing rain is true -- it's dangerous! The B1900D is a fantastic aircraft in icing conditions. However, not even this aircraft comes anywhere close to being able to deal with freezing rain. My best advice -- be aware of and avoid freezing rain at all costs, pilots!

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Original NASA ASRS Text

Title: AN ACR BE02 FLC RPTS ON THEIR ENCOUNTER WITH FREEZING RAIN. THEY WERE CORRECTLY QUITE IMPRESSED BY ITS RAPID EFFECT ON THE ACFT'S PERFORMANCE.

Narrative: A COLD FRONT WAS FORECAST TO MOVE THROUGH ARIZONA AND COLORADO DURING OUR FLT FROM GJT TO PHX. THE FIRST LEG OF THIS SCHEDULED TRIP (PHX-GJT) WAS COMPLETELY FREE OF INCLEMENT WX ENRTE. OUR FLT WAS ON THE GND APPROX 10 MINS IN GJT AND IT TOOK APPROX 25 MINS TO GO FROM GJT TO THE 80 NM N OF TBC. THEREFORE, FROM THE TIME WE FIRST PASSED THE AREA OF FREEZING RAIN ON OUR WAY TO GJT TO THE TIME WE ACTUALLY ENCOUNTERED IT WAS ONLY ABOUT 1 HR. WE FIRST ENCOUNTERED WHAT SEEMED TO BE LIGHT TO MODERATE MIXED ICING AT FL220. (OUR ACFT IS APPROVED FOR FLT INTO KNOWN ICING, COMPLETE WITH HEATED WINDSHIELD, LEADING EDGE BOOTS, HEATED PROPS, AND PNEUMATICALLY HEATED PT6-A ENG INLET LIP HEAT.) HOWEVER, AFTER A SHORT TIME, THE HEATED WINDSHIELD BEGAN ICING UP, AS WELL AS THE ENG INLET LIP AREA! THE INLET LIP HEAT IS HEATED TO APPROX 720 DEGS C BY DUCTING EXHAUST AIR THROUGH DUCTING UNDER THE LIP. WE NOTED THE OUTSIDE AIR TEMP OF 0 DEGS C, AND WERE CLRED TO 15000 FT MSL. THE TEMP (0 DEGS C) AND ICING CONTINUED ALL THE WAY DOWN TO 11000 FT MSL. MODERATE TURB OCCURRED THROUGHOUT THE FLT WHICH LASTED 2 HRS 25 MINS WITH A DIVERSION TO PRC FOR FUEL. A POSTFLT INSPECTION OF THE ACFT REVEALED LARGE PITS IN THE FUSELAGE PAINT ADJACENT THE PROPS AND PROP PAINT NICKED OFF FROM THE ICE. ALL THE LITERATURE ON FREEZING RAIN IS TRUE -- IT'S DANGEROUS! THE B1900D IS A FANTASTIC ACFT IN ICING CONDITIONS. HOWEVER, NOT EVEN THIS ACFT COMES ANYWHERE CLOSE TO BEING ABLE TO DEAL WITH FREEZING RAIN. MY BEST ADVICE -- BE AWARE OF AND AVOID FREEZING RAIN AT ALL COSTS, PLTS!

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.