Abstract: An example wing-in-ground effect vehicle includes (i) a main wing having main wing control surfaces; (ii) a tail having tail control surfaces; (iii) a blown-wing propulsion system arranged along the main wing or the tail; (iv) a retractable hydrofoil configured to operate in: (a) an extended configuration in which the retractable hydrofoil extends below a hull of the vehicle for submersion below a water surface and (b) a retracted configuration in which the retractable hydrofoil is retracted at least partially into the hull of the vehicle; and (v) a control system configured to maneuver the vehicle by (i) causing a change in orientation of the retractable hydrofoil when the retractable hydrofoil is operating in the extended configuration, and (ii) causing a change in orientation of the main wing control surfaces and tail control surfaces when the retractable hydrofoil is operating in the retracted configuration.