Turbo Normalised
I have been flying a C182 with Lycoming turbonormalised 540. It gives 32 inches of boost.
I don't understand it well enough. Anyone who has experience on it, please comment.
On takeoff it is normal, 32 inches, 2400 rpm and 24 gph. In cruise it initially allows normal set up of, say 25 inches and 2300 rpm with fuel flows around 14 and the TIT close to max. But after flying for a while I see the rpm is down to 2100, even with the prop control full in. It acts like a fixed pitch propeller, and moving the throttle to do maneuvers causes the rpm to fluctuate, around 2000 to 2300 even with full increase.
I had a bit of trouble with rough running, could only keep the engine going by using a very low mixture setting, but the mechanic found dirty plugs and cleaned the injectors which seemed to fix it.
On approach, prop full in, the rpm when the speed is 60 and the throttle is set to around 15 inches, is 1100. Even a Cessna 150 rpm is not that slow.
Once on the ground again, a run up is normal. Performance seems normal, although acceleration on takeoff is nothing to write about. The rate of climb two up and half fuel is around 600 fpm, a little slow I thought. A go around is best descibed as Stately. But cruise is 125 IAS with 25 inches of boost.
However it is the rpm that concerns me. My mechanic says I just don't understand the turbo normalised engines. To get used to it. He says the Cirrus is worse, but I don't fly the Cirrus so that is no help.