Somewhat ironically for a vehicle designed to reach orbital speed, the space shuttle’s flight control system was only certified for airspeeds up to 333 KIAS, and exceeding 470 KIAS (the maximum allowable in dire emergency) would have led to an immediate loss of control. This constraint was the reason for at least two, and possibly three, of the low-survivability zones in the event of a triple engine failure (go to page 14 of the linked PDF and look at the number of times it says “excessive EAS during pullout”1).
In contrast, essentially all modern jets have flight controls certified to well over 500 KIAS, and capable of safely controlling the aircraft at airspeeds considerably higher still.
Given the lethal effects of an overspeed-induced loss of control during an emergency situation, why were the shuttle’s flight controls certified with such a ridiculously low maximum airspeed?
1: Technically, it uses KEAS (knots equivalent airspeed) instead of KIAS (knots indicated airspeed), but, assuming that your airspeed indicator is properly calibrated and the pitot-static system on your aircraft is working properly, KEAS=KIAS.