carb ice experience

On 23 Oct 2005 08:27:50 -0700, wrote:

Another trick to stick in your pilots bag of magic is to use the primer
knob if your engine gets starved for carb ice and stops.

Ah, but that's on the instrument panel, and I fly from the back seat!

(A time or two, I've not noticed until I'm in the air that the field
altitude wasn't set, and I've had to add/subtract a hundred feet to
TPA etc. One time I was heading off on a crosscountry, and I landed in
a private field so I could set it correctly, which entails getting out
of the harness so as to reach forward across the front seat.)



-- all the best, Dan Ford

email: usenet AT danford DOT net

Warbird's Forum: www.warbirdforum.com
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What typically happens, and often under the exact conditions you
describe cold humid morning with frost on the ground is that as you
taxi out ice builds up in the carb reducing the RPM. You wil
subconsously keep adding power to keep it running like you want/need to
taxi. Then when you add power for the run up you will position the
throttle farther open than normal to get the 1500 RPM that you need
since the carb is partially iced up. When you add the Carb heat it will
typically drop a bit and then back up to a higher RPM. The RPM Surge
you saw was simple the result of having more ice that you are used to

I see this quite often in the Champs I Fly and even Cessna/pipers
occasionally.

Brian
CFIIG/ASEL