Sorry Pete but you are wrong. There is no way to change that.
Distance away from you has nothing to do with it.
If you are flying a 1/5th plane 20 feet from you at 70 mph it will look the same size as a full scale 100 feet away from you at 350mph. If it is 100 feet away from the crowd it will look like a full scale 500feet away. That is how scale works. It is not opinion, it is simple fact.It is easy to prove with a stick and a couple of cut out planes. The speed they need to fly to look the same will be scaled too.
Kentscalculations have nothingto do with visual scale speed.
My corsair will do 113 out of a dive and looks cool down the strip. It is not scale. Never will be unless the Corsair flew at 644. In fact at sea level the corsair flew at from 311 to maybe 340.
good luck bud
Paul