RE: flying at an airport
Not to take this thread too far off topic, but here it goes. I have also flown at an existing airport, and we always landed and got out of the way when we noticed a full scale aircraft nearing the airport. How does anyone know what 400' looks like. With a 40 or 60 size plane is it high enough that the plane is starting to look small and difficult to tell the orientation, or is it still clearly visible. I am in the construction industry and have layed out many buildings, roads and pipe lines, and I can tell you right now that 95% of the people I have come across cannot judge distance worth a darn horizontally, and that is much easier than looking at a model flying over our heads, where there is nothing to use a point of reference. If you dont understand what I am talking about, go outside and look at the side of the building your in guess how tall it is to the gutters. 1 story, 10' maybe 12'. Now take a tape measure and lay it on the ground and look at that distance. It doesnt look anywhere as long as the building looks tall.
So again my question is, How do you judge 400' vertically?