ORIGINAL: fliir
Inkjet decals are easy if you (or a friend) have an inkjet printer. You jus print it and then spray a clear acrylic over the top to protect it. The USAF Stencil font would be perfect!
Here is a waterslide decal that I printed on my inkjet printer:
I use Fliir's method to do all the decals on my Jet gear detail and other projects. If you need white letters on a painted surface, rubdown transfers ar your only option.
Paul