Guys, I'm not quite sure that "stalled prop" is correct terminology. I
think "slippage" might be more approprite. I don't think that there
something unusual happening, other than the prop is trying to push (and
pull in) more air than is available in a static position. It's similar

to a

slipping clutch that finally stops slipping when the car speed matches

the

engine speed. The prop is just running at a very low efficiency when
standing still.

I believe Ed's new engine is making more hp than the old one, and thus,

is

able to spin the prop at a higher rpm. As was suggested, he should watch
his t/o roll rpms to see if it goes up, or drop off a little. I had a
similar problem in that I had to throttle back on t/o, or risk
overreving/overboosting because the prop was slipping a lot. When he's
flying he will be able to tell if he needs a different prop (more pitch,
etc). You'd only change the prop now if your rpms are too low which

would

indicate too much pitch/too little hp.

Chuck Harbert

You are probably right about that Chuck.  "Stalled " prop was the term I
heard used but that would tend to imply as Vance suggested that the prop is
not going to turn any faster.  While "Slippage" would imply the prop is
turning faster because there is  insufficient airflow to load the prop
properly.

I will fly with this prop and see if it does the typical things a "Stalled"
prop is suppose to do.

Hopefully in the air Thursday or Friday depending on the weather.

Ed

 
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