Why not adopt the same refueling probe arrangement as the Malaysian MiG-29s...
You could possibly even add in an IRST ball like the MiG-29.
Looking at the engine side you could go RD33 or RD93 or even F404 or F414. Give it a thrust vectoring tail similar to the MiG-29OVT even...
This one is only intended as a quick fix for the "Good Guys" FC-1. Higher up the ladder would be based on J-7FS (attachment #1).
But, hum...... your suggestion should be interesting for an "Aces' Machine"......
Otherwise I'd like to reserve the title of Super MiG-21 for the tailless ones (attachments #2-#4) or the J-7MF (see
my earlier post). And they are too cool to be bad guys.
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Possibly fit a refuleing probe to teh MiG-21 similar to those fitted to Canadian F-5s? If memory serves me correctly, the MiG-21 has a very packed fuselage and adding a refueling probe would almost require it to be external and you'd want it to be away from the intake just to prevent problems.
The F-5-style one was the idea that I first had.
The MiG-29-style one seems external to me, like a package that includes a fairing that the probe can extend out of and then retract back into. I'm wondering if the F-5-style scheme would be lighter though.