The invention relates to an efficient pneumatic duct body. On the premise of guaranteeing the duct lip shape unchanged, the inner wall of the duct is slotted; on the one hand, the weight of the duct body is reduced while effective load is increased; and on the other hand, the fan
radius in the duct is increased so as to boost the lift force generated by the fan, and meanwhile, the flowing-around environment of the tip is effectively inhibited, the tip loss of the fan is reduced, and the fan efficiency is improved. With a switch, an opening operation can be performed at the duct body, and the duct lift force
system reduces the
momentum drag and parasite drag so as to adapt to the efficient pneumatic state of an aircraft during vertical flight and
forward flight.