Loss of engine power during IMC flight in severely cold WX factors.

Attributes
ACN	263542
Time
Date	199402
Day	Mon
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : dpa
State Reference	IL
Altitude	agl bound lower : 0 agl bound upper : 3000
Environment
Flight Conditions	IMC
Light	Night
Aircraft 1
Controlling Facilities	tracon : ord tower : dca
Operator	general aviation : instructional
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Operating Under FAR Part	Part 91
Flight Phase	cruise other landing other other
Route In Use	enroute : on vectors
Flight Plan	IFR
Person 1
Affiliation	Other
Function	instruction : instructor oversight : pic
Qualification	pilot : commercial pilot : instrument pilot : cfi
Experience	flight time last 90 days : 200 flight time total : 1200 flight time type : 40
ASRS Report	263542
Person 2
Affiliation	Other
Function	flight crew : single pilot instruction : trainee
Qualification	pilot : private
Events
Anomaly	aircraft equipment problem : critical inflight encounter other
Independent Detector	other flight crewa
Resolutory Action	controller : issued new clearance controller : provided flight assist flight crew : declared emergency flight crew : exited adverse environment other
Consequence	Other
Supplementary
Primary Problem	Weather

Narrative:

After initial climb out and level off at vectoring altitude, I experienced a loss (partial) of power after applying carburetor heat. No change so I asked for priority 1 and a turn back to the airport we just departed. I tried carburetor hear again but to no avail, the engine continued to loose power. I tried to maintain altitude and airspeed but the engine continued to lose power. The controller continued to give vectors and cleared me for localizer runway at dpa. The engine finally just went to idle so we were cleared for 'altitude at pilot's discretion.' I then put the airplane into a shallow descent to keep best glide speed. We continued to approach and finally broke out of the clouds at 1000 ft AGL and made a normal landing. Once on the ground I tried a normal run-up but the aircraft engine wouldn't exceed 1500 RPM. I believe we had a severe case of carburetor ice and the engine wasn't warm enough to melt it away with carburetor heat on.

Original NASA ASRS Text

Title: LOSS OF ENG PWR DURING IMC FLT IN SEVERELY COLD WX FACTORS.

Narrative: AFTER INITIAL CLB OUT AND LEVEL OFF AT VECTORING ALT, I EXPERIENCED A LOSS (PARTIAL) OF PWR AFTER APPLYING CARB HEAT. NO CHANGE SO I ASKED FOR PRIORITY 1 AND A TURN BACK TO THE ARPT WE JUST DEPARTED. I TRIED CARB HEAR AGAIN BUT TO NO AVAIL, THE ENG CONTINUED TO LOOSE PWR. I TRIED TO MAINTAIN ALT AND AIRSPD BUT THE ENG CONTINUED TO LOSE PWR. THE CTLR CONTINUED TO GIVE VECTORS AND CLRED ME FOR LOC RWY AT DPA. THE ENG FINALLY JUST WENT TO IDLE SO WE WERE CLRED FOR 'ALT AT PLT'S DISCRETION.' I THEN PUT THE AIRPLANE INTO A SHALLOW DSCNT TO KEEP BEST GLIDE SPD. WE CONTINUED TO APCH AND FINALLY BROKE OUT OF THE CLOUDS AT 1000 FT AGL AND MADE A NORMAL LNDG. ONCE ON THE GND I TRIED A NORMAL RUN-UP BUT THE ACFT ENG WOULDN'T EXCEED 1500 RPM. I BELIEVE WE HAD A SEVERE CASE OF CARB ICE AND THE ENG WASN'T WARM ENOUGH TO MELT IT AWAY WITH CARB HEAT ON.

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.