a fresh air inlet for an aircraft features a ram air inlet with a ram air inlet opening , a secondary air inlet opening separate from the ram air inlet and a movably mounted flap . the flap can be moved into a first or second position , and essentially covers the secondary air inlet opening in the first position and at least partially opens the secondary air inlet opening and extends away from the aircraft body in the second position to shield the ram air inlet opening from foreign matter in the air . the secondary air inlet reduces the pressure loss of the air inlet on the ground or during flight phases with relatively slow speed due to the enlarged cross - sectional surface . the ram air inlet can be optimized for cruising phases , and the energy expenditure for any downstream compressors and flow - induced noises can be considerably reduced .