United States Patent 3799446

An engine for inducing the flow of fluid through a duct is provided ahead of a pair of sets of rudder vanes disposed at the discharge side of the duct which is of V-configuration having the apex of the V turned in the direction of fluid flow. Each set of vanes comprises a plurality of generally flat but aerodynamically shaped vanes swingable about respective vertical axes by independent controls for the vehicle direction so that either set may completely block or only deflect the fluid stream traversing the window of the outlet spanned by the set of vanes.

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International Classes:
B60V1/14; B64C9/38; (IPC1-7): B63H25/46
Field of Search:
180/116,117,118,120 239
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Primary Examiner:
Tollberg, Stanley H.
Assistant Examiner:
Bartuska, Francis J.
Attorney, Agent or Firm:
Ross, Karl Dubno Herbert F.
I claim

1. A rudder for a vehicle comprising a duct traversable by fluid in the direction of vehicle movement and having an intake end and a discharge end; means in said duct for inducing a flow of fluid therethrough from said intake end to said discharge end, said discharge end being formed with a pair of windows lying in vertical planes symmetrically inclined rearwardly and intersecting one another at a line perpendicular to the longitudinal axis of said duct and forming angles of substantially 30° with a vertical plane perpendicular to said axis; a respective set of vertical generally flat but aerodynamically shaped flaps mounted in each window and having parallel vertical pivot axes about which each flap is swingable at an intermediate location along its width between a first extreme position in which the flaps of each respective set lie substantially in the respective window plane and obstruct the window, and a second position in which the flaps of each set are oriented to deflect a fluid stream through the window approximately 60° from the direction of flow with said flaps parallel to the axis of said duct; and respective controls for individually orienting the flaps of each set.

2. The rudder defined in claim 1 wherein three flaps are provided for each of said sets, the flaps of each set being linked for joint rotation in parallel relationship.


The present invention relates to improved rudders for vehicles with aerodynamic or hydrodynamic propulsion.


In general vehicles with aerodynamic propulsion are steered by deflection of the propulsion-fluid stream or a fluid stream traversing the vehicle as it is displaced through an ambient fluid to deflect the stream and thereby turn the vehicle in one direction or the other depending upon the degree of deflection or its direction.

The disadvantage of the use of deflectors is that, when the fluid stream is to be deflected through more than 15°, the fluid separates from the deflecting surface and the control effect is reduced. The problem is especially pronounced at low speed and hence large-area deflectors must be provided in these cases and the steering efficiency is reduced.


It is the principal object of the present invention to provide a steering arrangement for an aerodynamic or hydrodynamic vehicle whereby the aforementioned limitations are eliminated.


I am able, with the rudder of the present invention, to increase the effective deflection angle to 30° or more and thereby obtain improved steering even at low speeds. This is achieved by channeling the flow of fluid to the rudder vanes which are rotatable about axes lying in two intersecting planes including angles of about 30° with the plane perpendicular to the axis of the channel or duct at the aforementioned intersection, the vanes being flat bodies of aerodynamic configuration which are pivotal between positions in which they lie parallel to the axis of the duct into positions in which they lie substantially parallel to the aforementioned axis plane and obstruct fluid flow through the windows. The fluid emerging from the trailing end of the duct may be deflected up to about 60° by the vertical control surfaces.


The above and other objects, features and advantages of the present invention will become more readily apparent from the following description, reference being made to the accompanying drawing in which:

FIG.1 is a perspective view of an aerodynamic rudder for a vehicle using a ducted air screw for propulsion;

FIG.2 is a side-elevational view of a rudder of the type shown in FIG.1 but in axially shorter configuration and with a portion of the engine removed;

FIG.3 is an axial section taken along the line A -- A' of FIG.2;

FIG.4 is an axial section similar to FIG.3 but showing the vanes in an intermediate deflected position;

FIG.5 is a view similar to FIG.4 showing the vanes in an extreme position; and

FIGS.6 and 7 are perspective views of an air-cushion vehicle using the rudder system of the present invention.


In the drawing, I have shown a ducting ring 1 receiving a propelling air screw 2 and having a discharge end which is formed with a pair of laterally and rearwardly opening windows formed by the intersection of respective planes inclined to the longitudinal axis of the duct or ring and intersecting along a vertical line perpendicular to this axis. The two symmetrical vertical planes 3 each form an angle of about 30° with a plane perpendicular to the plane of the paper in FIGS. 2 and 3 and to the longitudinal axis A -- A'. The vertical intersection line 4 lies in the longitudinal symmetry plane of the ducting ring 1.

On each side of this symmetry plane, there are arranged three vertical control surfaces 5 in the form of vanes of aerodynamic profile having their trailing edges extending in the direction of air flow. Each of the vanes 5 is mounted for rotation about a vertical axis 6 journaled by bearings in the trailing edges of the ducting ring 1. The vertical axes 6 of the vanes 5 are formed as axles which are kinematically connected to directional steering controls 7 by levers 8 and 9 so that each of the sets of vanes may be controlled individually.

The directional steering controls 7 operate the sets of control flaps 5 whereby the latter may be deflected from the neutral positions (FIG.3) to an intermediate position (FIG.4) deflecting the fluid stream to the right and into a position (FIG.5) in which one of the windows is blocked and the fluid stream through the other window is deflected through about 60°.

The channeling of the fluid flow permits the flaps 5 to remain effective as deflecting surfaces through angles of up to 60° as illustrated and separation of this stream of fluid from the surface does not occur to the detriment of the steering operation.

In FIGS. 6 and 7, the two sets of flaps 12 are provided with axes in the intersecting vertical planes 10 having the intersection line 11. The vertical axles are here shown at 13 and the flaps are controlled by individual linkages as previously described and similar results are obtained as have been described for the embodiments of FIGS. 1 - 5.