I really hate the whip antennas. You spend hundreds, sometimes thousands of hours perfecting details, and then you have that big old ugly antenna coming out that makes everything look like a toy from Toys'R'Us (just look at Wolfgang Klührs MiG.......perfect, except.......).
I had my sabre with an internal antenna without any range problems, and it looked great. My F-15 will have it internally as well, running up inside the stab.
Just get it away and clear of carbon components, they severely shield off any signals that are coming in. Another thing that really helps: make sure you can "see" about 50% of the antenna no matter what angle you are looking at it. That way you will get consistent range from all angles without "dead spots" and "unlimited range spots". (My main worry with whip antennas is that when looking straight from the top you get almost 0 projected antenna area, thus least range.....yet you usually have exactly that attitude when you are furthest away, turning back inbound!!! Range checks on the ground hardly ever feature "top view").
So much to the theory.....i'll post some pics of the new sabres antenna setup as soon as i get it installed and range checked.