Darryl, The speed of WWII aircraft is misunderstood out there. Lets take a Mustang. Sure it could do 400 at 30,000ft with everything to the firewall but for a short time because you'd be burning 120+gph. Take a fully loaded Mustang with a couple of full drop tanks and we are talking about 180-190mph cruise. At 55% cruise power a clean Mustang will do around 250. It does very nice aerobatics between 180 and 250 any faster and the ailerons get pretty heavy. So a 1/5 scale Mustang should fly in the 40 -65mph range to be scale. A 1/7 scale doing 100 is going way too fast for scale but you know who cares as it sure looks cool flashing past. Don