Narrative:

I was en route from madison, wi, to ennis, mt, and stopped for fuel at pierre, sd. Received a WX briefing from FSS and also used computer at pierre flight planning center. Although there was a general airmet for icing in the area, I noted 2 PIREPS in the area with tops at 10000 ft and negative icing. A third PIREP was received by an arriving C310 pilot in the lounge who said tops were 8000 ft, negative ice. We departed pir around XA00 local and with our clearance climbed to 10000 ft on V2. We were still in the clouds at 10000 ft, but negative ice. I noticed after dupree VOR (dpr) the sky above seemed bright suggesting we were flying in the cloud tops. About that time we were instructed by ZMP to contact ZLC when 80 mi from MLS VOR. We were 98 mi from MLS. At 90 mi from MLS, I noticed we were getting ice accumulation on the leading edge and struts. I tried to contact ZLC several times and also went back to ZMP frequency with no response. At 83 mi east of MLS, we had lost 25 KTS of airspeed and had 1 inch of mixed ice on all leading edge, strut, and tail edge surfaces. I announced my intentions to ZLC frequency and set 7700 in transponder and began a descent to the MOCA on the airway of 6600 ft. I continued my attempts to contact ZLC during descent. At 7000 ft, another airplane began relaying our radio calls to ZLC controller. We were IMC, but negative ice at 6600 ft and followed ATC instruction to MLS. After flying the 17 DME arc to VOR approach to MLS, we landed without incident. The ZLC controller did an excellent job verifying our position and maintaining a calm and helpful and very professional approach. The lessons learned: 1) problem arose by maintaining an altitude at the top of the clouds. This is an area known for icing and I knew that, although the PIREPS suggested not. 2) the situation was made worse by losing radio contact with ZMP. I should have advised them of the potential icing and need for a climb or descent. A cruise clearance to 14000 ft might have also given us more flexibility. I should have maintained communication until out of IMC. 3) I think a 180 degree turn might have been another option if action would have been taken immediately. The ice accumulated quickly and I did not feel a 180 degree turn was the safest route given our loss of airspeed. 4) since I had an IFR certified GPS on board, I was not concerned about the navigation signal reception issues associated with the MOCA or terrain clearance altitude. I also felt that the risk of other airplanes being below the MEA of 10000 ft was remote from a risk management perspective. 5) I believe that I performed quality decision making after discovering we were getting ice. I believe the fact that I was on portable oxygen aided my clear thinking at that time. 6) I had the perception that declaring an emergency was a bad thing and delayed my response to a serious icing incident. I also was reluctant to leave my assigned altitude and this magnified the amount of ice I tolerated prior to descent. I feel in the future I would take quicker action to assure the safety of the flight. 7) in the future, I will make certain that if I need to change altitude or route due to WX or icing conditions, I will do so prior to losing or accepting a loss of communication. I will either maintain communication until situation is resolved or contingencies are arranged.

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Original NASA ASRS Text

Title: C182RG PLT ON IFR FLT PLAN ENCOUNTERED ICING AND LOSS OF CONTACT WITH ARTCC.

Narrative: I WAS ENRTE FROM MADISON, WI, TO ENNIS, MT, AND STOPPED FOR FUEL AT PIERRE, SD. RECEIVED A WX BRIEFING FROM FSS AND ALSO USED COMPUTER AT PIERRE FLT PLANNING CTR. ALTHOUGH THERE WAS A GENERAL AIRMET FOR ICING IN THE AREA, I NOTED 2 PIREPS IN THE AREA WITH TOPS AT 10000 FT AND NEGATIVE ICING. A THIRD PIREP WAS RECEIVED BY AN ARRIVING C310 PLT IN THE LOUNGE WHO SAID TOPS WERE 8000 FT, NEGATIVE ICE. WE DEPARTED PIR AROUND XA00 LCL AND WITH OUR CLRNC CLBED TO 10000 FT ON V2. WE WERE STILL IN THE CLOUDS AT 10000 FT, BUT NEGATIVE ICE. I NOTICED AFTER DUPREE VOR (DPR) THE SKY ABOVE SEEMED BRIGHT SUGGESTING WE WERE FLYING IN THE CLOUD TOPS. ABOUT THAT TIME WE WERE INSTRUCTED BY ZMP TO CONTACT ZLC WHEN 80 MI FROM MLS VOR. WE WERE 98 MI FROM MLS. AT 90 MI FROM MLS, I NOTICED WE WERE GETTING ICE ACCUMULATION ON THE LEADING EDGE AND STRUTS. I TRIED TO CONTACT ZLC SEVERAL TIMES AND ALSO WENT BACK TO ZMP FREQ WITH NO RESPONSE. AT 83 MI E OF MLS, WE HAD LOST 25 KTS OF AIRSPD AND HAD 1 INCH OF MIXED ICE ON ALL LEADING EDGE, STRUT, AND TAIL EDGE SURFACES. I ANNOUNCED MY INTENTIONS TO ZLC FREQ AND SET 7700 IN XPONDER AND BEGAN A DSCNT TO THE MOCA ON THE AIRWAY OF 6600 FT. I CONTINUED MY ATTEMPTS TO CONTACT ZLC DURING DSCNT. AT 7000 FT, ANOTHER AIRPLANE BEGAN RELAYING OUR RADIO CALLS TO ZLC CTLR. WE WERE IMC, BUT NEGATIVE ICE AT 6600 FT AND FOLLOWED ATC INSTRUCTION TO MLS. AFTER FLYING THE 17 DME ARC TO VOR APCH TO MLS, WE LANDED WITHOUT INCIDENT. THE ZLC CTLR DID AN EXCELLENT JOB VERIFYING OUR POS AND MAINTAINING A CALM AND HELPFUL AND VERY PROFESSIONAL APCH. THE LESSONS LEARNED: 1) PROB AROSE BY MAINTAINING AN ALT AT THE TOP OF THE CLOUDS. THIS IS AN AREA KNOWN FOR ICING AND I KNEW THAT, ALTHOUGH THE PIREPS SUGGESTED NOT. 2) THE SIT WAS MADE WORSE BY LOSING RADIO CONTACT WITH ZMP. I SHOULD HAVE ADVISED THEM OF THE POTENTIAL ICING AND NEED FOR A CLB OR DSCNT. A CRUISE CLRNC TO 14000 FT MIGHT HAVE ALSO GIVEN US MORE FLEXIBILITY. I SHOULD HAVE MAINTAINED COM UNTIL OUT OF IMC. 3) I THINK A 180 DEG TURN MIGHT HAVE BEEN ANOTHER OPTION IF ACTION WOULD HAVE BEEN TAKEN IMMEDIATELY. THE ICE ACCUMULATED QUICKLY AND I DID NOT FEEL A 180 DEG TURN WAS THE SAFEST RTE GIVEN OUR LOSS OF AIRSPD. 4) SINCE I HAD AN IFR CERTIFIED GPS ON BOARD, I WAS NOT CONCERNED ABOUT THE NAV SIGNAL RECEPTION ISSUES ASSOCIATED WITH THE MOCA OR TERRAIN CLRNC ALT. I ALSO FELT THAT THE RISK OF OTHER AIRPLANES BEING BELOW THE MEA OF 10000 FT WAS REMOTE FROM A RISK MGMNT PERSPECTIVE. 5) I BELIEVE THAT I PERFORMED QUALITY DECISION MAKING AFTER DISCOVERING WE WERE GETTING ICE. I BELIEVE THE FACT THAT I WAS ON PORTABLE OXYGEN AIDED MY CLR THINKING AT THAT TIME. 6) I HAD THE PERCEPTION THAT DECLARING AN EMER WAS A BAD THING AND DELAYED MY RESPONSE TO A SERIOUS ICING INCIDENT. I ALSO WAS RELUCTANT TO LEAVE MY ASSIGNED ALT AND THIS MAGNIFIED THE AMOUNT OF ICE I TOLERATED PRIOR TO DSCNT. I FEEL IN THE FUTURE I WOULD TAKE QUICKER ACTION TO ASSURE THE SAFETY OF THE FLT. 7) IN THE FUTURE, I WILL MAKE CERTAIN THAT IF I NEED TO CHANGE ALT OR RTE DUE TO WX OR ICING CONDITIONS, I WILL DO SO PRIOR TO LOSING OR ACCEPTING A LOSS OF COM. I WILL EITHER MAINTAIN COM UNTIL SIT IS RESOLVED OR CONTINGENCIES ARE ARRANGED.

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.