Originally Posted by gasman
Now that's a very educational (to me) post!.....
"is only optimised for one particular speed." And what speed would that be for our 360 RV's?
I assisted a friend installing the Decathlon
engine/prop combo you mention onto an RV4 with no mods many years ago and it worked very well. The blade shape on this particular Hartzell model is optimized for the Decathlon's lower entry aerobatic speed range around 120 KIAS,
but will still provide reasonable top end speed but at a slightly higher RPM/MP as I recall. We operated from my short turf strip and it provided decent STOL performance as well. Realize this prop is specifically designed for the I0-320 on the 8KCAB Decathlon
. The 0-320 has a very different harmonic vibration footprint than the 0-360 as well which requires a placard for a 2000-2250 continuous RPM avoidance range in the 8KCAB. Food for thought. BTW, I had no problems keeping up with him in climb and cruise in my own 0-320/Sterba wood prop RV4.
As Hans so eloquently stated, propellers are compromises in performance and designers look at aircraft with specific blade designs in mind.
[Personally, I prefer a well designed Fixed Pitch Propeller for the 0-320 RV4. This produces a light nose, low flywheel effect and no RPM restrictions for Aerobatics and the occasional 1V1.
PS: The only Van's approved CS props specifically designed for the 0-320 powered RV
are the Hartzell 2 blade, MT 2/3 blade listed on vansaircraft.com and the Whirlwind 200RV.