The abort system is like ejection seats: the greater the part of the flight envelope it works in, the better, because you have smaller portions of the flight th

The abort system is like ejection seats: the greater the part of the flight envelope it works in, the better, because you have smaller portions of the flight that problems are unsurvivable. The abort system tests were for the most difficult regimes of flight: maximum dynamic pressure, and zero altitude, zero airspeed. Having tested that, they can be sure it'll work in less difficult sections.