Narrative:

3-5 mins before the incident; I descended into IMC at 4600 ft for an assigned altitude of 4000 ft. The temperature before entering the clouds was 4 degrees C. After reviewing the approach; I examined the wing for ice and the outside air temperature. The temperature in the clouds was -2 degrees C and there was slightly less than 1/2 inch of rime or mixed ice on the wing. I decided to engage the inertial separator; which required a significant power reduction for 4-6 seconds. Before the power was fully reapplied; the aircraft entered a complete stall. There were no preceding signs of an imminent stall detected. There was no control lightness; no large pitch increase; pre-stall buffet; stall warning horn; or other airplane sound or feel to indicate a stall. The recovery took 500-600 ft before controled flight was regained. My scan during the recovery showed an airspeed of 120 KIAS; fully stalled. The weight of the aircraft at the time of the incident was 8500 pounds.

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Original NASA ASRS Text

Title: A C208 ACCUMULATED ABOUT 1/2 INCH OF RIME OR MIXED ICE AT 4600 FT AND -4 DEGS C. AS DEICE SYS ACTIVATED; THE ACFT ENTERED A FULL STALL AT 120 KTS; RECOVERING IN 500-600 FT.

Narrative: 3-5 MINS BEFORE THE INCIDENT; I DSNDED INTO IMC AT 4600 FT FOR AN ASSIGNED ALT OF 4000 FT. THE TEMP BEFORE ENTERING THE CLOUDS WAS 4 DEGS C. AFTER REVIEWING THE APCH; I EXAMINED THE WING FOR ICE AND THE OUTSIDE AIR TEMP. THE TEMP IN THE CLOUDS WAS -2 DEGS C AND THERE WAS SLIGHTLY LESS THAN 1/2 INCH OF RIME OR MIXED ICE ON THE WING. I DECIDED TO ENGAGE THE INERTIAL SEPARATOR; WHICH REQUIRED A SIGNIFICANT PWR REDUCTION FOR 4-6 SECONDS. BEFORE THE PWR WAS FULLY REAPPLIED; THE ACFT ENTERED A COMPLETE STALL. THERE WERE NO PRECEDING SIGNS OF AN IMMINENT STALL DETECTED. THERE WAS NO CTL LIGHTNESS; NO LARGE PITCH INCREASE; PRE-STALL BUFFET; STALL WARNING HORN; OR OTHER AIRPLANE SOUND OR FEEL TO INDICATE A STALL. THE RECOVERY TOOK 500-600 FT BEFORE CTLED FLT WAS REGAINED. MY SCAN DURING THE RECOVERY SHOWED AN AIRSPD OF 120 KIAS; FULLY STALLED. THE WT OF THE ACFT AT THE TIME OF THE INCIDENT WAS 8500 LBS.

Data retrieved from NASA's ASRS site as of January 2009 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.