6 x 4.5 Alternative to the 6 x 4.
6 x 5 Popular and successful prop. Best used under 5.5" diameter.
A4 (5.6 x 5.5) An all new shape. Works well if you have the power to pull it.
A42 (5.5 x 5.0) A smaller variation of the A4, proving to be very popular.
A5 NYA New single blader with an integral counterweight.
Props for Australian Sports 45 pylon, the rules vary around the country, in some states it is compulsory to run a commercial 10 x 6 unmodified.
10 x 6SP (sport pylon) enjoys a very good reputation for performance. This prop is supplied ready to 'bolt on' in order to meet the rules.
9.25 x 7 often cut down to smaller diameters. Best in c/f only.
GENERAL: It cannot be stressed enough, that a successful pylon model is one where the complete power-plant and model are correctly matched with themselves and the weather. The dominant factor in engine performance is heat (see 2 stroke theory).
For prop selection it is a compromise between high acceleration (high diameter or area) Vs straight line speed (high pitch). Often a low pitch prop will give faster race times (than high pitch) due to its faster turning / cornering ability. For sports models, wind is a dominant factor. The 8.5 x 7 may be best in calm and 10 x 6SP the best in wind, but less successful when roles are reversed.
PROPS FOR R/C OLD TIMER
Bolly Props are especially suited to competition 'Old Timer' events. Where the rules limit the power plant (as in OT) the biggest advantage is in the propeller.
Despite selling large quantities of props to old timer enthusiasts, very little information is at hand to specific applications. The 13 x 6
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