Replacement Motors & Props
     Our closest rubber motor match is the .0938" (M377). It is at the high end of the motors supplied with the kit. You may compensate for increased mass per unit cross section by increasing prop pitch, which will slow the prop speed. If this increases thrust more than is desired, you may compensate if the plane climbs too quickly by backing off some winds (experiment to see how many). The real issue is the total mass of rubber. Width is not entirely reliable, since thickness varies a little. There is probably no single ideal value for motor weight and prop pitch taken together. 
Important: You MUST attach an O-ring to the tail end of the motor to facilitate removing and replacing the motor from the motor hook for winding. Hold the motor at 30 degrees from the fuselage while winding, and have your partner hold a cardboard sheet between the motor and fuselage to protect the airplane from damage if you lose control of the motor while winding. Wind about 1/3 to half the winds while stretching the motor to 5x to 7x its length, then walk in slowly while winding the remainder. 
     Ikara props - same as those included in kit - are available on our construction supplies page.

Try this experimental idea for better performance.
     When a motor stick is under the linear and torisonal load of a fully wound motor, it may bow or twist slightly. This results in a change in the angle of the stabilizer relative to the wing, and may cause erratic performance during the critical first seconds after launch. Symptoms include
1) airplane dives on launch.
2) airplane rotates (rolls) left and dives at launch (added wash-in on the left wing can help)
3) airplane hardly climbs and flies in "pylon turns" at relatively high speed.
4) airplane climbs slightly during the last seconds of flight then enters a stall.
     Tom Sanders has offered a truly elegant solution. Instead of attaching the  tailboom to the end of the motor stick, use a longer tailboom of sufficient thickness and attach it at the front on the top of the motor stick, approximately where the prop hanger is mounted. This isolates the stab from distortions of the motorstick caused by motor loading.

      
Just for fun...
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