The pilots of fighter aircraft can survive accelerations of over 9g (wearing the right suit and performing the recommended muscle bracing techniques). When being pursued by a missile, their ability to escape is limited by their own physiology, rather than the manoeuvrability of their planes.
People are notoriously bad at behaving randomly, so any missile worth its salt can probably predict a pilot’s changes of direction well enough, once it gets close, to be able to score a hit.
Today’s invention is therefore a system which detects when a missile has locked on, gains height rapidly and then automatically undertakes a rapid, random sequence of spins, jinks and darts, always keeping each acceleration of the plane below the damage level for the individual pilot in question.
(The human body is much more tolerant of g-force when it is applied across the body than along its length and pilots are already tested in centrifuges to determine their passing-out thresholds).
Each plane would thus know the limits of its crew -making for a very rough ride, but no rougher than ejection and certainly preferable to the alternatives.