Narrative:

C340. IFR aircraft equipped with deice boots, hot propellers, pitot/stall heat. Not certified for known icing -- no windshield heat. Had checked WX with FSS en route and again by computer on ground at ZZZ1 for next leg to ZZZ2. Failed to update with FSS for ZZZ2 WX en route. I wonder if I missed something regarding WX -- no PIREPS of icing. A couple of broken layers at ZZZ2. Ceiling high enough -- alternate not required. Fuel less than full due to passenger load, but I did plan fuel for approach, divert to airport 60 mi away and approach/land +45 mins response. Did not see any airmets for icing, but knew of possibility in the mountains. En route, headwinds stronger than forecast at altitude. Compensated by flying lower and reduced power to save fuel. But, 15-20 mins of reserve fuel used. Arrival, vectored off route by center. Delay in approach clearance awaiting turn at 16000 ft. Light rime ice in clouds. As vectored away from IAF, a jet reported moderate clear ice in descent 17000-15000 ft. ATC called to my attention. This delay plus headwind used much of my reserve fuel. Radioed center I would be minimum fuel in 5 mins, but ATC said unreadable, but vectored me a little closer and told to expect approach clearance in 2 mins. Started moderate rime ice, asked for lower, but ATC unable since was vectored off route. Cycled boots to clear approximately 1/2 inch ice on leading edges. Windshield accumulated ice, -- turned defrost on high with no effect. Problem: most of reserve fuel used. Icing. No approach clearance yet. To divert, would have to fly through it more plus fly right over the desired destination airport. Most expeditious way out was to continue and hopefully get clearance in 2 mins as promised. Distrs: broken radio transmission (ice on antenna?), transponder showed wrong altitude, switched to #2 transponder. Got approach clearance, descended to 12000 ft. No more ice. Started ILS runway 19. Intended to land no matter what, so flew best ILS I could. Tower called visual on me approximately 4 mi out, but ice on windshield obscured my view completely (almost). Saw airport out top of windscreen, but would be unable to see ahead in flare. Mentally prepared to land using ILS and looking at edge of runway. Ice melted off windscreen approximately 600 ft AGL giving clear view. Landed without incident. Lessons learned: 1) assume worst in mountains. What was legal fuel wasn't sufficient given icing. 2) examine WX data better -- bet there was a clue to expect icing as possibility. 3) declare emergency if you think you won't be able to see on landing due to ice on windshield. 4) declare emergency to get immediate clearance if you can't go lower to get out of icing. 5) don't forget en route WX updates.

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Original NASA ASRS Text

Title: A C340 PLT ARRIVED AT HIS MOUNTAINOUS DEST WITH LOW FUEL AND MODERATE WINDSHIELD ICE.

Narrative: C340. IFR ACFT EQUIPPED WITH DEICE BOOTS, HOT PROPS, PITOT/STALL HEAT. NOT CERTIFIED FOR KNOWN ICING -- NO WINDSHIELD HEAT. HAD CHKED WX WITH FSS ENRTE AND AGAIN BY COMPUTER ON GND AT ZZZ1 FOR NEXT LEG TO ZZZ2. FAILED TO UPDATE WITH FSS FOR ZZZ2 WX ENRTE. I WONDER IF I MISSED SOMETHING REGARDING WX -- NO PIREPS OF ICING. A COUPLE OF BROKEN LAYERS AT ZZZ2. CEILING HIGH ENOUGH -- ALTERNATE NOT REQUIRED. FUEL LESS THAN FULL DUE TO PAX LOAD, BUT I DID PLAN FUEL FOR APCH, DIVERT TO ARPT 60 MI AWAY AND APCH/LAND +45 MINS RESPONSE. DID NOT SEE ANY AIRMETS FOR ICING, BUT KNEW OF POSSIBILITY IN THE MOUNTAINS. ENRTE, HEADWINDS STRONGER THAN FORECAST AT ALT. COMPENSATED BY FLYING LOWER AND REDUCED PWR TO SAVE FUEL. BUT, 15-20 MINS OF RESERVE FUEL USED. ARR, VECTORED OFF RTE BY CTR. DELAY IN APCH CLRNC AWAITING TURN AT 16000 FT. LIGHT RIME ICE IN CLOUDS. AS VECTORED AWAY FROM IAF, A JET RPTED MODERATE CLR ICE IN DSCNT 17000-15000 FT. ATC CALLED TO MY ATTN. THIS DELAY PLUS HEADWIND USED MUCH OF MY RESERVE FUEL. RADIOED CTR I WOULD BE MINIMUM FUEL IN 5 MINS, BUT ATC SAID UNREADABLE, BUT VECTORED ME A LITTLE CLOSER AND TOLD TO EXPECT APCH CLRNC IN 2 MINS. STARTED MODERATE RIME ICE, ASKED FOR LOWER, BUT ATC UNABLE SINCE WAS VECTORED OFF RTE. CYCLED BOOTS TO CLR APPROX 1/2 INCH ICE ON LEADING EDGES. WINDSHIELD ACCUMULATED ICE, -- TURNED DEFROST ON HIGH WITH NO EFFECT. PROB: MOST OF RESERVE FUEL USED. ICING. NO APCH CLRNC YET. TO DIVERT, WOULD HAVE TO FLY THROUGH IT MORE PLUS FLY RIGHT OVER THE DESIRED DEST ARPT. MOST EXPEDITIOUS WAY OUT WAS TO CONTINUE AND HOPEFULLY GET CLRNC IN 2 MINS AS PROMISED. DISTRS: BROKEN RADIO XMISSION (ICE ON ANTENNA?), XPONDER SHOWED WRONG ALT, SWITCHED TO #2 XPONDER. GOT APCH CLRNC, DSNDED TO 12000 FT. NO MORE ICE. STARTED ILS RWY 19. INTENDED TO LAND NO MATTER WHAT, SO FLEW BEST ILS I COULD. TWR CALLED VISUAL ON ME APPROX 4 MI OUT, BUT ICE ON WINDSHIELD OBSCURED MY VIEW COMPLETELY (ALMOST). SAW ARPT OUT TOP OF WINDSCREEN, BUT WOULD BE UNABLE TO SEE AHEAD IN FLARE. MENTALLY PREPARED TO LAND USING ILS AND LOOKING AT EDGE OF RWY. ICE MELTED OFF WINDSCREEN APPROX 600 FT AGL GIVING CLR VIEW. LANDED WITHOUT INCIDENT. LESSONS LEARNED: 1) ASSUME WORST IN MOUNTAINS. WHAT WAS LEGAL FUEL WASN'T SUFFICIENT GIVEN ICING. 2) EXAMINE WX DATA BETTER -- BET THERE WAS A CLUE TO EXPECT ICING AS POSSIBILITY. 3) DECLARE EMER IF YOU THINK YOU WON'T BE ABLE TO SEE ON LNDG DUE TO ICE ON WINDSHIELD. 4) DECLARE EMER TO GET IMMEDIATE CLRNC IF YOU CAN'T GO LOWER TO GET OUT OF ICING. 5) DON'T FORGET ENRTE WX UPDATES.

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.