I have been privy to a bunch of testing by a University. Our engines pull air from wherever they can get it. You can put a plate at the end of the starter. If there is enough area around the plate to get enough air in it will run fine, temps normal and thrust normal. Doesn't help drag, aircraft speed, etc. but will not effect engine. No way the boat tail messes with the engine.
Check out this one. A bunch of testing. for non aerodynamic reasons the inlet was best on top. The engine front was centered on the hole on top.
Last edited by why_fly_high; 02-27-2018 at 01:08 PM.