Disgorging on the fly in Champagne is an ancient disgorging technique used by winegrowers (some still do) and the major Champagne houses, before the advent of ice disgorging.
For large containers, certain vintages or small quantities, we still practice manual disgorging, known as "à la volée ", i.e. we hold the bottle upside down and open it, straightening it quickly so that the pressure expels the deposit without letting too much wine escape.