B-24 & B-25 tail design

Both Joint Strike Fighter candidates (X-35 and X-36) had single engines and double tails. The X-35 is destined to become the F-35 and replace the F-16, F/A-18, AV-8B Harrier, and A-6 Intruder in US and allied service. I’m sure that General Dynamics had a reason for going with a single tail rather than double tails on the F-16, most likely weight and complexity, since the F-16 was intended as an inexpensive, lightweight dogfighter.

Fighters are also designed as far as possible to avoid having any inside right-angle intersections, which have the nasty characteristic of reflecting radar beams right back at the sender. The F/A-18, for instance, has the vertical stabilizers canted to each other and at an odd angle to the fuselage top, and forward of the horizontal stabilizers, just for that reason. With a single tail, it’s hard to avoid having a right angle at the fuselage junction, and stealth considerations may outrank weight and drag in the design.