Definitions for "Fly-Back Hand"
An additional second hand on a chronograph that can be used for timing in competition. To record the duration of a competition, just stop the fly-back hand. This fly-back hand can be stopped independently and made to catch up ("fly-back") with the other constantly moving second hand. Use repeatedly when needed.
In a chronograph with analogue display, an additional centre second hand which can remain superposed on the other one as it moves, can be stopped independently and then made to "fly back" so as to catch up with the other hand, can be stopped and reset to zero together with the other hand. In chronographs with numerical display, a "function" having the same effect.
An additional hand on a chronograph which moves with the second hand but, can be stopped independently to measure an interval which can then "fly back" to catch up with the other hand.