This is re,lated to Newtons first law of motion.
According to his law "Every body has tendency to renain in state of rest or travel in the straight line unless it is acted upon by an external forces."
Actually the person feels increase in his weight becaus there is increase in the magnitude of g.
Suppose his normal weight is 'mg' . The weight felt by the person while taking of will be,
'm[g+gsin(angle of elevation)]'
