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Lancair folks,
Tuesday I had another flying learning experience. I took off in my L4P from Sedona, AZ. at 9:45AM and 90*F in the morning to avoid the afternoon widespread Lightning storms that I saw the previous two days starting about noon. There were hi clouds with bases at about 12/15K ft. I saw a large hole open up overhead that was kinda on my route west so I thought I could get on top at FL240, which was what I had filed for. I had full fuel (108 gals) two folks, 4 cats and luggage (gross). I made a left climbing 270* overhead departure to get through the hole before calling ATC for my IFR flight plan. It mostly worked fine but I hadn't got on top by the time the hole was gone so I asked for deviation on heading of up to 40* left to avoid the build ups. I could see that we were going to have to go IMC so I turned on the Pitot heat and turned off the AC. I had the TruTrak AP holding heading and climbing at 700 fpm. I saw #2 cyl. temp rising at 9.5K ft. so I turned on the Low Boost, which is normal at 10K ft., and it stabilized the temps at 415*. I went IMC at 17K ft. and continued climbing to my cleared FL 220. I still wasn't on top and my cylinder head temps. were climbing like I had never seen them before. I had full rich and had checked my fuel flow on take off at full power (43.8 GPH at 38.5/2700 rpm) which is right at max flow. My cruise climb was 29 GPH at 31.5/2550 rpm. So with the temps rising I put the HI Boost on and saw 33 + GPH and then I reduced MP to 30. The temps were still rising till I had #2 at 436* and 3 others at over 420* which shows as Red warnings on the SFS and the lady is telling me in my ear to "Check Engine". I didn't know what was happening and went pasted my assigned altitude of 220 and then the controller reminded me. I told her I wanted higher and that I had an overtemp problem. She gave me FL230 as max. I leveled there and was still IMC but could see that if I was 1,000 ft. higher I would be out of most of this. I asked for 240 and they said no way. By then I had pulled power back to 29/2400 with Hi Boost and still the temps remained higher than I have ever seen before. So I went on the Lean side 29/2400 gave me 17.5 GPH and the temps that usually come right down stayed over 420* (4) in the red and the rest in the yellow. After about 20 min. of IMC we broke out not even seeing Las Vegas. For the first time I looked out and saw I had 1/8 in. of rime ICE on the wing and wingtits up and over the top of them. I had noticed a 20 to 30 kt. decrease in TAS and 12 to 16 less in IAS. My temps were not going down and maybe going up so I again went back on the Rich side and turned on the HI Boost. I had lots of fuel for this 500 NM flight and the SFS showed a 2.5 hr fuel remaining on the rich side as compared to 4.5 hrs on the lean side. I was pouring as much fuel into the engine as possible and didn't want to go any less on RPM than 2400 at this altitude and take the chance of loosing pressurization. I carried that ICE for at least 1.5 hrs of the 2.2 hr flight. I didn't loose the Ice until I descended below 17K ft the freezing level.
Bottom-line, this is my first encounter with ICE in the L4P and I wanted to ask anyone with experience if they have ever noticed the engine CHT's being your first indication of ICE? I suspect that the front of the cowl openings had enough Ice to disrupt the cooling air flow. After landing in 90* at San Jose, CA. I looked into the cowl and fist thought that with my landing lights mounted in the right air intake that maybe they iced up, but than I remembered that it affected all CHT's on both sides. My left side is almost stock with only the AC lines over the intercooler. BTW, when flying on top at FL 230 after coming out of IMC, with the sun at high noon, I had the sun shades on the window and the AC turned on low to keep it comfortable in the cabin AND ICE on the leading edges. I never thought that would be the case. With the AC off I felt the incoming air from the Turbos through the intercooler and I must say that it was cold, but after having the AC off for 10 min. it gets warm in the cabin and the AC on low makes it perfect, the cats love it.
Hope this helps others, please give me your comments,
Jim Hergert
N6XE, "An Sex Y" L4P
190 hrs. SFS
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