RC Prop Charts

Prop Chart For Two - Stroke Engines

Alternate Propellors	Starting Prop	Engine Size
5.25x4, 5.5x4, 6x3.5, 6x4, 7x3	6x3	.049
7x3,7x4.5,7x5	7x4	.09
8x5,8x6,9x4	8x4	.15
8x5,8x6,9x5	9x4	.19 - .25
9x7,9.5x6,10x5	9x6	.20 - .30
9x7,10x5,11x4	10x6	.35 - .36
9x8, 11x5	10x6	.40
10x6,11x5,11x6,12x4	10x7	.45
10x8,11x7,12x4,12x5	11x6	.50
11x7.5, 11x7.75, 11x8,12x6	11x7	.60 - .61
11x8,12x8,13x6,14x4	12x6	.70
12x8,14x4,14x5	13x6	.78 - .80
13x8,15x6,16x5	14x6	.90 - .91
15x8,18x5	16x6	1.08
16x10,18x5,18x6	16x8	1.20
18x8,20x6	18x6	1.50
18x10,20x6,20x8,22x6	18x8	1.80
18x10,20x6,20x10,22x6	20x8	2.00

Prop Chart For Four - Stroke Engines

Alternate Propellers	Starting Prop	Engine Size
9x5,10x5	9x6	.20 - .21
10x6,10x7,11x4,11x5.11x7,11x7.5,12x4,12x5	11x6	.40
10x6,10x7,10x8,11x7,11x7.5,12x4,12x5,12x6	11x6	.45 - .48
11x7.5,11x7.75,11x8,12x8,13x5,13x6,14x5,14x6	12x6	.60 - .65
12x8,13x8,14x4,14x6	13x6	.80
13x6,14x8,15x6,16x6	14x6	.90
14x8,15x6,15x8,16x8,17x6,18x5,18x6	16x6	1.20
15x6,15x8,16x8,18x6,18x8,20x6	18x6	1.60
18x12,20x8,20x10	18x10	2.40
18x10,18x12,20x10	20x8	2.70
18x12,20x10	20x10	3.00

Starting Propeller sizes are mid range pitch props that should fly just about any plane designed for that size engine. Use these first as in most cases they will be close to being the correct size. Then use trial and error to try and fine tune the maximum performance from your ship by trying the alternate props. If none work better stick with the recommended starting prop.