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Old 09-27-2021, 05:10 PM
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Georges Payne
 
Join Date: Apr 2007
Location: Saguenay, QC, CANADA
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Default Not getting the RPM predicted by eCalc

Hi all! Returning modeler after 10 years here!

I have a Hangar 9 Valiant 10cc with a E-flite power 52 and APC 12x8electric, a Castle Creation Phoenix Ice 100A, and 6000 mah 4S 100C Gens Ace Li-po batteries. It's all NOS if you will, bought at various points in the past but never used, except for the batteries which I bought last week from Great Hobbies in Canada. The plane weighs 6.25 lbs all up so it's easily within the specs.

Before returning to the field after a hiatus of more than 10 years I practiced a lot with RealFlight 9.5 using my Spektrum DX8 transmitter and a USB receiver. I am lucky in the sense that the Valiant 10cc with electric motor is in the simulator, so I could prepare for it as closely as possible. My problem is I get nowhere near the performance that I get in RealFlight. So I subscribed to eCalc and input all my parameters as precisely as I could. The RPM predicted by eCalc is 7749 RMP at max efficiency, and 7918 RPM at maximum. Measuring the actual RPM at full throttle with a full battery on my bench, I get 6700 RPM max. The auto throttle calibration features seems to be working, I changed the endpoints beyond 100% to make sure and the ESC adapted accordingly.

I just ordered a Castle Link USB V3 programming kit because I want to make sure that the ESC is not limiting the motor for some reason. But from the looks of it, there is no way to program the maximum RPM is Castle Link. Since this is my first serious electric powered plane, I thought I would ask the Pros. Always got good advice here in the past.

Thanks for any tips you guys can provide!
George