if you are curious what size your model would be to your eyes at 400 feet-measure 400 feet from two points on ground, have someone hold your model up in a attitude you normally see if when flying, take a ruler and hold up and start at the nose and read the ruler where the tail stops while standing on one of the points you initially marked off. Take the measurement off of the ruler and make a measure stick with the same length you read on the on ruler and also put two vertical end strips on the measuring stick you made. You can also install a piece of stick on the bottom rail of the measure stick for a handle. Now you can go fly your model and manually check your altitude with this reference device and to know how high you are. I do not have one anymore but it does work -I would post a picture because I do not know if you can follow these instructions but I am building a new bird now and need nothing else on work bench.
Last edited by PLANE JIM; 01-01-2016 at 06:43 PM.