Is the need for carb heat affected by ambient humidity?

It sure is. I tried to take off once in Shenandoah on a humid day, and
the engine failed its runup - when I pulled the power back, it quit
entirely. I did this a few times and called the mechanic over. We
couldn't find anything - the final theory was that carb ice had built up
while I was taxiing and during the runup. This had never happend to me
before, in this aircraft, or any other.

I preflit and took off with carb heat, and had no problem.

Jose
--
He who laughs, lasts.
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