Rotary-wing aircraft with propellers separate - has airstream from propellers discharging downwards into vertical ducting around lift rotors

摘要

The rotary-wing aircraft is basically as known as in 26 34 837 with two or more contrarotating lift-rotors and one or more propellers in a combined casing above a cabin unit and driven by the same power unit. The lift-rotors have substantially vertical ducting. That for the propeller(s) runs longitudinally, underneath the rotors in the lift ducting; is of aerofoil-section with the chord vertical. At least some of the propeller ducting (17-20) now has outlets into the lift ducts (11, 12), these outlets being pref. downward-pointing. With a tractor-propeller, the inboard (18, 19) pref. open into the forward (11), the outboard (17, 20) into the after, lift duct (12).