I didn't reinforce mine, remember if you make anything heavy enough it won't get off the ground. The engineers at ICP don't believe you need them. Reg designed his rudder extension after a conversation we had on the phone one night, about three days later I went over to start building and the parts were on the bench, but he did what seemed necessary, he is not an engineer. The only example is the old maroon Savannah demonstrator and it has a new home down at Dubbo, I don't know of any photos of the angle reinforcements.