I have a Futaba 9C. I often fly for a full day and can have the radio on for 4+ hours. When I fly slope soaring flights can easily extend over an hour. I have a 2500 MAh pack in mine. I charge it with my Triton peak charger but I also charge it with the stock wall charger. I just leave it on for 20-30 hours on the wall charger. Works fine.