ORIGINAL: a1pcfixer
ORIGINAL: jsallade
Agreed he'll be turning some high RPMs. As I said, it's (after doing some math) about 83% of the minimum recommended load for that engine. A better way (in my experience) to calculate what fits for pitch/diameter is to take dia*dia*dia*dia*pitch (i.e. dia to the 4th power and multiply by pitch). This gives you a rough ''loading'' number. ............................
Here's a sample for the DLE-20:
14 10 384160
16 6 393216
15 8 405000
14 11 422576
16 7 458752
14 12 460992
17 6 501126
15 10 506250
16 8 524288
Nice chart, but, does it take into consideration; H.P., torque, rpm, temperature, etc., etc???
The mathematics are cool, but go back and listen to the video of his DLE20 in flight, it's screaming as it passes by!
The chart is only showing the load on the engine put by the prop. Nothing to do with the engine parameters. This is the load on any engine. Now you need to work out how much you want to load YOUR engine based on this data. I often use this to calculate the other combination of dia and pitch that may be suitable for an engine, given the best rated prop. For it.
For the DLE20 the best rated prop is the 17x6 but using the above chart you may use 14x12, 15x10, 16x8 also and be within 10% of the ideal load on the engine.
The data above is the volume of air moved by the prop - pitch x dia^2 x constant (pi/4)