In fluidics, forces in vehicles occur via circulation control, in which larger more complex mechanical parts are replaced by smaller simpler fluidic systems (slots which emit air flows) where larger forces in fluids are diverted by smaller jets or flows of fluid intermittently, to change the direction of vehicles.[10][11][12] In this use, fluidics promises lower mass, costs (up to 50% less), and very low inertia and response times, and simplicity.[citation needed]