I've often wondered: why is it that, on some aircraft, there is a gap between the engine inlet and the fuselage? For example, both the F-16 and F-4 Phantom II...
Photo © Ivo Medrik - TIMCZ
Photo © Georg Noack
Are the aerodynamics more favorable when the inlet is not flush with the fuselage, or is there another reason for this gap? Other fighter aircraft seem to have it as well, such as the Eurofighter and the Mirage 2000..
What's the deal here?