I scratch built a trenton terror old timer from a half page plan in Model Builder. It had a 6 ft wingspan and weighed about 3.5#. Powered it with a .25fp diesel and a 12x3.5 prop. 45 minutes easy on a 4 oz tank. I used to have people come up and ask me if i was going to fly and then i would point up and say 'I am flying'. Just trimmed it for a slow turn and slight climb and set the transmitter down.