If the pressure on the lift face (upper face) of the foil drops to the vapour pressure of the water, vapour bubbles will be formed which collapse when they enter a region of higher pressure.
Ukuba uxinzelelo kunyuso-buso (ubuso obuphezulu) bentsimbi eyasu-yasu behlele kumphunga woxinzelelo lwamanzi amaqamza omphunga azakwenzeka aphinde athi folokohlo xa angena kummandla woxinzelelo oluphezulu.