WATFORD WAYFARERS

Model Aero Club

 

Prop Chart For Two - Stroke Engines


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

Standard 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 standard prop.

Prop Chart For Four - Stroke Engines

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