We have a long running debate in our group regarding the Yak 52 carb heat (or not). Can you operate yours in flight? We have to back off the speed to about 170kph before we can move the lever !
Hi, SATCO B,
I know what you mean, it is not easy to go from cool to warm with any kind of speed on. 170kph seems a sensible limit for trying.
And the whole engineering of the thing is less-than-perfect, especially that hinge at the back.
I too have used it only infrequently in flight, and have not had a lot of trouble hitherto. But I shall be using it more in future. Never had carb icing at steady power of 60%/6 or above, but a couple of months ago I landed somewhere just as it was starting to drizzle, and at the end of the landing roll found I couldn't open the throttle to taxi off the grass runway! (as you know that's a pretty infallible sign of carb icing on a Yak). Fortunately I had a few knots on and was slightly downhill so able to clear the runway while I whacked it into warm air for a couple of minutes - problem solved. And then the other day I had a sticky throttle coming out of a spin recovery. It gave me a little bit of throttle, enough to maintain level flight at 170kph and 82%, but didn't want to go forward past that and I was keen not to use excessive force and risk bending the linkage. So again I put it into warm air, looked at fields (but was at 6000 feet so loads of options) and two minutes later exercised the throttle gently and all back to normal. Again, it was an absolutely classic carb icing day, prop throwing offf contrails at run-up, little wispy patches of vapour visible at all levels.
I've decided next time I'm doing stalls or spins I'll put it into warm air for the last thousand feet of the climb and the clearing turns, and leave it there until I restore normal cruise or high-power aeros.