Thanks for your replies. While I have no doubt the F-16 carries the Viper nickname today, I'd be very curious as to when the interview referenced on F-16.net was conducted?
Back in the early 1990s, quite a few squadrons began or planned conversion onto F-16s from other platforms. These conversions were usually accompanied by semi-official, and unofficial patches to commemorate the change. To the best of my knowledge, none of these unofficial/commemorative patches reference the jet as Viper. I can understand Fighting Falcon on official patches since it's the official name of the jet. A good example was the planned conversion to F-16s by both the CT and MA ANGs back in 1991. Patches were duly produced and the A-10s are proudly referred to as Hogs while the F-16s are referenced as Falcons.
If the Viper nickname was in place back in the early 1980s, I'm a bit confused why the name doesn't really appear anywhere? I suspect the name came along quite a bit later -- probably mid-90s.

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