palgia I think that there is a simpler version of the equation shown below, but I cannot locate it at this time, so the JAR-AWO reference will have to do. The equation relates to the minimum approach break off height (MABH) in Cat 3 operations, which I think approximates to the height loss during a GA or a value slightly greater than the actual height loss … you did ask!!!
Ref JAW-AWO 313
Ah = 0.155 (VS squared) + (0.0017 (square root W) + 3.2) VS
where
Ah = MABH (ft)
Vs = rate of descent (ft/sec) at MABH in still air using the approach speed scheduled for 90% of W
W = maximum landing weight (lb)
Sprite is far more practical.