Narrative:

Obtained WX briefing 2 hours before flight from tulsa, ok, to cos. Forecast clear, 1 hour east of lamar, skies became cloudy. Called flight watch 20-30 mi east of lamar. Had trouble hearing. Cos, IFR with 1000 ft ceiling. Called ZDV and received IFR clearance to cos, climbed to 9000 ft in the clear. Slow speed, headwind about 100 KTS. Entered cloud about 25 NM from cos (VOR). Started picking up ice, did not react. Looked out and thought, 'that's not very much ice.' airplane started to slow down and I could not maintain altitude. Realized I was close to a stall, speed about 80 KTS and handling poorly. Advised ATC about ice and could not maintain altitude. ATC gave me a turn toward lower terrain (south) and also toward airport. Airplane continued to descend, all I could do. Broke out of clouds and ATC vectored me to airport (straight ahead). Landed without incident. I could not have flown even a few mi further. What strikes me is that I continued to fly into danger, hoping I could complete the approach. It was in my head that I had to follow ATC's instructions, and I waited for ATC to direct me out. It was like I was lulled into taking no action. It was a report to ATC by an incoming airliner of icing that triggered me to report icing on my aircraft.

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Original NASA ASRS Text

Title: A GA SINGLE ENGINE CFI FLIES INTO ICING CONDITIONS AND RECEIVES VECTORS FROM ZDV CTLR FOR A LNDG AT COS.

Narrative: OBTAINED WX BRIEFING 2 HRS BEFORE FLT FROM TULSA, OK, TO COS. FORECAST CLR, 1 HR E OF LAMAR, SKIES BECAME CLOUDY. CALLED FLT WATCH 20-30 MI E OF LAMAR. HAD TROUBLE HEARING. COS, IFR WITH 1000 FT CEILING. CALLED ZDV AND RECEIVED IFR CLRNC TO COS, CLBED TO 9000 FT IN THE CLR. SLOW SPD, HEADWIND ABOUT 100 KTS. ENTERED CLOUD ABOUT 25 NM FROM COS (VOR). STARTED PICKING UP ICE, DID NOT REACT. LOOKED OUT AND THOUGHT, 'THAT'S NOT VERY MUCH ICE.' AIRPLANE STARTED TO SLOW DOWN AND I COULD NOT MAINTAIN ALT. REALIZED I WAS CLOSE TO A STALL, SPD ABOUT 80 KTS AND HANDLING POORLY. ADVISED ATC ABOUT ICE AND COULD NOT MAINTAIN ALT. ATC GAVE ME A TURN TOWARD LOWER TERRAIN (S) AND ALSO TOWARD ARPT. AIRPLANE CONTINUED TO DSND, ALL I COULD DO. BROKE OUT OF CLOUDS AND ATC VECTORED ME TO ARPT (STRAIGHT AHEAD). LANDED WITHOUT INCIDENT. I COULD NOT HAVE FLOWN EVEN A FEW MI FURTHER. WHAT STRIKES ME IS THAT I CONTINUED TO FLY INTO DANGER, HOPING I COULD COMPLETE THE APCH. IT WAS IN MY HEAD THAT I HAD TO FOLLOW ATC'S INSTRUCTIONS, AND I WAITED FOR ATC TO DIRECT ME OUT. IT WAS LIKE I WAS LULLED INTO TAKING NO ACTION. IT WAS A RPT TO ATC BY AN INCOMING AIRLINER OF ICING THAT TRIGGERED ME TO RPT ICING ON MY ACFT.

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.