Multiple propulsion units mounted inside an enclosure near openings can be used to control the fluid flow in and out of the openings and also to determine the total fluid flow at any additional uncontrolled openings. By controlling the fluid flow, where such control is available, and by considering the resulting flow at any uncontrolled enclosure openings, it may be possible to achieve a desired thrust vector but have a more favorable weight/shape/efficiency than would be possible without the enclosure and use of coordinated control of fluid flow into or out of some openings. The designed geometry of the enclosure is an important consideration and will have an effect on the overall thrust magnitude and direction. A grouping of propulsion systems can be coordinated to achieve a more general thrust vector and associated moment on a vehicle.