I spent this morning flight testing an E-Prop on my RV-12iS. I installed the prop with the recommended pitch of 25 degrees. That was on Tuesday and the weather was not flyable but I was able to do a static run at WOT. My static rpm was 5700. I felt this was going to be too high and that the prop would need more pitch but the E-Prop instructions said that if the static rpm was between 5000 and 5800, go fly. So today I did. I was climbing at 1550 fpm vs 1100 under similar conditions with the 2 bladed Sensenich prop. At WOT straight and level the rpm was climbing through 5760 when I throttled back and landed.
I increased the pitch to 26.2 degrees and flew again. Much improved! I was climbing at about 1250 fpm and WOT in straight and level the engine was at 5620 RPM and 125 knots.
I increased the pitch to 26.5 degrees and gave it another try. After the flight I decided this is what I would stick with for now. WOT in cruise is 5560. My rate of climb is 1200 fpm (5160 rpm in climb at 75 IAS) and at 5100 rpm straight and level my TAS is 120 burning 3.6 gph (MAP 25.7 inches). With the Sensenich prop I cruised at 110 TAS at 5100 rpm burning 3.8 gph. The test was done at a GW of 1100 lbs. The engine goes out of ECO mode at and above 5200 rpm resulting in high fuel burns. So, I gained about 10 knots and 100 fpm over the Sensenich. I decided I was going to go for speed vs climb.
The prop is VERY smooth. Starts and stops are amazing. No clunking or kicking. Plus, it looks SO much better than the Sensenich. On the way back to the airport I was testing some power settings and at 4000 rpm I was cruising at 97 knots at burning 2.2 gph. The plane is 9 lbs lighter and the CG moved aft 3/4 of an inch.
Henry
I increased the pitch to 26.2 degrees and flew again. Much improved! I was climbing at about 1250 fpm and WOT in straight and level the engine was at 5620 RPM and 125 knots.
I increased the pitch to 26.5 degrees and gave it another try. After the flight I decided this is what I would stick with for now. WOT in cruise is 5560. My rate of climb is 1200 fpm (5160 rpm in climb at 75 IAS) and at 5100 rpm straight and level my TAS is 120 burning 3.6 gph (MAP 25.7 inches). With the Sensenich prop I cruised at 110 TAS at 5100 rpm burning 3.8 gph. The test was done at a GW of 1100 lbs. The engine goes out of ECO mode at and above 5200 rpm resulting in high fuel burns. So, I gained about 10 knots and 100 fpm over the Sensenich. I decided I was going to go for speed vs climb.
The prop is VERY smooth. Starts and stops are amazing. No clunking or kicking. Plus, it looks SO much better than the Sensenich. On the way back to the airport I was testing some power settings and at 4000 rpm I was cruising at 97 knots at burning 2.2 gph. The plane is 9 lbs lighter and the CG moved aft 3/4 of an inch.
Henry
Last edited:
