A double-ducted fan includes a hub, a rotor having a plurality of blades rotatably and coupled to the hub, a first duct, a second duct, and a channel defined between the first duct and second duct. The first duct circumscribes the rotor, and the second duct circumscribes at least a portion of the first duct. The second duct can be oriented axially upward such that there is an axial distance is between the leading edges of the first duct and second duct. The channel can be configured to direct air flow cross-wise to the first duct over a top of the first duct into the inlet side of the fan. The second duct can be movable relative to the first duct to adjust at least a portion of the channel. The length of the first duct can be different from the length of the second duct.