I power a 1/4 scale (100" span) Piper Cub with a Zenoah 23 petrol engine and use the FEMA compact starter. The starter is powered by an onboard Lithium power pack (11.1v 2500mAh) and speed controller. The system works reliably and safely and the aircraft is very easy to fly even with the added weight. I have not tried restarting the engine in flight and hope I will never need to! The FEMA unit is very well produced and the instructions clear.
I can fill up the tank and take the aircraft and tx to the flying field and fly, no hassle!
I use a separate NiCad to power the radio.
Paul
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