Maximum allowable airspeed for these aircraft:
F-4C, D, E = 750 KIAS
F-14A = 780 KIAS
F-15C = 800 KIAS
Unfortunately I can't find my data for the MiG-23 but I believe it was above 800 KIAS as was the F-111 IIRC.
Normal bird strike requirement for the canopy on most aircraft about 450 KIAS for a 4 lb. bird. I always kept that little item in mind during high speed low level flight.
BBadanov you got there as I was posting.