A technique of operating an unmanned aerial vehicle (UAV) adapted for a package delivery mission includes: powering distributed propulsion units during takeoff and landing segments of the package delivery mission and idling at least a portion of the distributed propulsion units while powering a pair of outboard propulsion units during a cruise segment of the package delivery mission. The distributed propulsion units are mounted below fixed wings of the UAV and have first propellers mounted fore of the fixed wings. The outboard propulsion units are each mounted to a corresponding one of the fixed wings outboard of the distributed propulsion units. The outboard propulsion units include outboard propellers having a larger diameter than the first propellers.