Before I go out and try this..how do you know how much rudder to use when doing this test? Im guessing that you should use just enough to make the plane turn? If thats the case, then then when you go to do a knife edge pass,you need to make sure the speed and rudder deflection are the same as when you did the flat turns? Ive tried a few times but it seems it takes a whole lot more to get the flat turn perfect then is actually needed for knife edge flight