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Radio Controlled models of F-16s fly fine without computer controlled flight systems. Apparently these model aircraft are not unstable in pitch but probably positive in pitch stability. There may be trade offs in high AoA capability but it would seem that an F-16 with sufficiently forward CG would be able to fly using conventional or hydraulic controls like for example the F-4 or F-5.

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I did some searching and got an extremely interesting answer here: By the way, I should have worded my question differently : the F-16 does have hydraulically powered controls, but the pilot inputs are sent through a computer first.

They designed the plane so it could be fitted with conventional hydro-mechanical controls if the fly-by-wire system couldn’t be made to work acceptably. “We spaced the bulkheads so that we could move the wing back and have a statically-stable airplane,” says Hillaker. “We were just giving ourselves some insurance. The wing would have had to have been moved back eighteen inches. All we had to do was make the two bulkheads have the same load capacity. One of them that we would’ve moved the wing to was higher than it needed to be, unless you moved the wing back.” The structural differences carried over to the production F-16 design, but fortunately were never needed. The fly-by-wire system’s control problems were quickly ironed out and the plane, even with all its advanced features, steadily gained support both in the U.S. and abroad

So model makers note: get the CG for the F-16 and move it back 18 inches or whatever the equivalent is on your model for a stable airplane.

http://www.f-16.net/articles_article13.html

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Well an RC model is going to have a different center of mass point than the real thing. Second, an F-16 is actually dynamically stable in subsonic flight; it requires a flight control computer for transonic and supersonic flight due to the shift in the center of pressure on the wings during this transition.

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  • $\begingroup$ The F-16 is said to have 'relaxed stability' in flight, for transonic and supersonic flight the all moving tail plane would probably be used to trim the plane for flight, as is done on the non- fly by wire F-5 and T-38 Talon. $\endgroup$ – stackex555 Apr 17 '17 at 8:34
  • $\begingroup$ But every supersonic airplane experiences such a shift. It then requires a different balance (trim) and control ratios (from stick to elevator) to have acceptable handling. A computer is handy for that (as long as it has guaranteed reliability), but in fact the airplane becomes more stable at supersonic, and thus could be handled conventionally. A stability augmentation system per se is needed mostly for subsonic flight. $\endgroup$ – Zeus Apr 18 '17 at 9:25
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Actually, some model aircraft use a "computer system" similar to the real thing, only much more simple. They have gyros that detect the attitude of the aircraft and the inputs of the pilot to determine if the maneuver was intentional, or due to some outside force, and will counter it as needed.

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