sentences:  It was not until the development of the Rogallo kite in the late 1940s that there was large scale interest in unpowered kite flying once again.The possibility of untethered flight on man-lifting kites eventually led to the development of hang gliders and paragliders.The sport of parasailing employs towed kites but anchored and tethered static man-lifting kites have seen little development, chiefly due to the lack of control inherent in the tethered design.