2-Cycle Engines			4-Cycle Engines
Engine Size	Starting Propeller	Alternate Propeller	Engine Size	Starting Propeller	Alternate Propeller
.049	6x3	5-1/4x4, 5-1/2x4, 6-3-1/2, 6x4, 7x3	.20 - .21	9x6	9x5,10x5
09	7x4	7x3, 7x4-1/2 7x5	.40	11x6	10x6,10x7 11x4,11x5 11x7, 11x7-1/2, 12x4,12x5
.15	8x4	8x5, 8x6, 9x4	.45 - .48	11x6	10x6,10x7 10x8,11x7 11x7-1/2, 12x4,12x5 12x6
.19 - .25	9x4	8x5, 8x6, 9x5	.60 - .65	12x6	11x7-1/2, 11x7-3/4, 11x8,12x8 13x5,13x6 14x5,14x6
.29 - .30	9x6	9x7, 9-1/2x6, 10x5	.80	13x6	12x8,13x8 14x4,14x6
.35 - .36	10x6	9x7, 10x5, 11x4	.90	14x6	12x10,13x8 14x8,15x6
.40	10x6	9x8, 11x5	1.20	16x6	14x8,15x6 15x8,16x8 17x6,18x5 18x6
.45	10x7	10x6,11x5, 11x6,12x4	1.60	16x6	15x6,15x8 16x8,18x6 18x8,20x6
50	11x6	10x8,11x7, 12x4,12x5	2.40	18x10	18x12,20x8 20x10
.60 - .61	11x7	11x7-1/2, 11x7-3/4, 11-8,12x6	2.70	20x8	18x10,18x12
.70	12x6	11x8,12x8, 13x6,14x4	3.00	20x10	18x12,20x10
.78 - .80	13x6	12x8,14x4, 14x5	Pitch: Think of pitch in the same way you think of threads on a screw. A pitch of 6 means in one revolution, a propeller should move forward 6 inches. Generally, greater pitch yields faster cruising speeds; lesser pitch provides better climbing. Starting Propellor 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. Watchouts: Keep loose clothing, shirt sleeves, and other such items away from the prop and avoid carrying objects that can fall into the prop such as pens, screwdrivers, etc. Be sure to keep the glow driver wire out of the prop path. If a spinner is used, be certain that it's edges are not in contact with the propeller blades.
1.08	16x6	15x8,18x5
.90 - .91	14x6	13x8,15x6, 16x5
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