GB2394707A - Wing for a surface or ground effect aeroplane - Google Patents

Abstract

An aeroplane for use in surface or ground effect flight comprises at least one wing 6 which comprises one or more panels 5 which is/are bent into an arch by a member or members under tension 3. These members in turn can help to effect control by adjusting their tension, in turn varying the geometry of the wing(s) 6. A tailplane 4 of similar construction may also be attached for stability reasons. The wing may conform to a section of a cone and the aeroplane may comprise a plurality of wings which may be attached to a fuselage (fig. 4) for ease of take off or landing on land or water.

Description

PANELLED AEROPLANE

The invention relates to aeroplanes and especially those that operate within surface effect.

The earliest attempts at designing aircraft to operate just above the surface of water were contemporaneous with the original development of the aeroplane. Perhaps because of this their outline, fabrication and means of control share much in common. In particular the use of a cantilevered wing of conventional cross-section and construction is ubiquitous.

The invention replaces these wings by the use of plain panels which derive their strength and aerodynamic properties from being arched like a bow. This is of especial use to vehicles designed for skimming flight, which though inherently less complex than free flight has to date proven quite elusive. A principal reason for this elusiveness, however, is that most vehicles of this kind have proven at least initially expensive as other aeroplanes, while not nearly so capable.

Under the present invention a wing is arranged by flexing a panel, or a series of adjoined or overlapped panels, by the use of cable or other tensional member. The panels are flexed into an arch along their span, so that the wing supporting the aircraft forms a single arch, or ideally a pair. The regularity of this arch at its various points depends among other things on the arrangement of members used to stress it out of its original shape.

The same technique can be used to contrive sailplane or stabiliser as well as a mainplane.

It can also be adapted as a manufacturing process, so that for instance its principles are employed in the production of wings which can subsequently be hardened into a more permanent form. Equally the basic tenets of suspension and assembly could be used by wings made of fabric and stressed separately with battens or inserts, seen elsewhere in sailcraft and ultralight aircraft alike.

Different examples of the invention are described with reference to the accompanying diagrams. These include the following: Figure 1 shows the simplest arrangement of arched wings around a central axis Figure 2 shows the same techniques adapted for a surface-going or skimming sled Figure 3 also shows a catamaran layout but with a pair of ram-wings and Figure 4 depicts a trimaran type.

In the first diagram two separate panels of planar material (1) have been joined along their lower axis (2) like the folded wings of a butterfly, but then arched by cables (3) attached to that same axis. What is immediately apparent is that flexing one or other side by the same means lends the vehicle a means of control in flight, by a system of wing warping. This control could be lent to pitching moments as well as to turns. Although the outline might be rendered flight-stable, particularly by the provision of ballast forward of

the axis (2), in this case a tail (4) has been added by similar means. In this example each panel (1) might comprise a series, as indicated by the pecked lines dividing them (5).

In Figure Two the same means have been used to span a single arch (6) with a tail (4) constructed in the same way. Notice from this that the tail (4) might be set at a greater angle of attack to provide natural height-stability once travelling in surface-effect. In fact the mainplane here might form a simple tunnel of constant radius and set at a constant level or angle of attack. Alternatively it might effectively form a section through a cone, so that its curvature reduces or flattens out toward the rear to create a "ram" wing. The fuselage might be located on top of the mainplane (6) along with a motor and propeller, situated in the gap between mainplane (6) and tail (4). Under a variation the sailplane (4) might coincide with or overlap the rear section of the larger wing. Again it will be clear that adjusting the flexure of the vehicle could determine its course in water or air, while it might also be provided with wheels to the same effect.

Figure Three combines these various approaches in a pair of coned wings (1) set upon a catamaran (7) joined at the rear by a tail (4) of a single piece.

The final diagram shows an ideal type in which wing area is maximised. Much like the first, it supports a pair of mainplanes (6) subdivided into panels (5) with an independent stabiliser (4) on each formed in much the same way. The layout lends itself to trimaran form, with a centrally placed fuselage (8) able to support a payload and propeller (9).

Motive means for land and water might be included along with conventional controls from each sphere of operation. The wings (6) in this case are "coned off" to create a ram-

wing profile and also terminate in pontoons in which wheels (10) may be incorporated.

The central fuselage (8) might support more substantial undercarriage. To form profiled or tilted sections the panels would normally appear tapered prior to assembly.

A feature of the rigging is that it might be muliplexed like a web and so draw the fabric of the wings into irregular curves. In its simplest form cables (3) such as these may be passed under or through the fuselage (8) to connect with each wing (6). Alternatively they may be divided effectively into separate halves. Each mainplane (6) might be joined independently of, or by dint of, the fuselage (8) itself.

What will be immediately apparent from all of the diagrams is that each vehicle, whilst durable in use, could readily be disassembled and stored or transported as a flat-pack. The materials used in each panel may be quite diverse and generally laminated, or selectively built up so as to adjust its characteristics. For instance it might be buoyant in itself, whether it is cellular or inflated to achieve this property. Also the use of more rigid fabrics which in themselves resist bending forces does not preclude the sort of stiffening or bettering the techniques would require for more pliable fabrics like sail-cloth. Neither is the combination of such wings in use with more conventional flying or control surfaces (and in particular a T-tail) inconceivable.

Claims (10)

r CLAIMS

1. A wing formed of one or more rigid panels bowed across their span by members under tension forming them into an arch.

2. A wing as in Claim I accompanied by a sailplane formed in a similar way.

3. A wing as in Claim 2 in which the sailplane is set at a different angle of attack.

4. A wing or sailplane as claimed in ay preceding clam wherein the tension can be adjusted to effect control.

5. A wing as claimed in any preceding claim in which the panels are prearranged to create a section through a geometrical cylinder or cone along its length, so that the arc of curvature may be adjusted in its radius or extent.

6. A wing as claimed in Claim 5 whose trailing edge or trailing edges taper instead of being parallel.

7. A wing as claimed in any preceding claim used in combination with another or in support of a fuselage, catamaran or trimaran body.

8. A wing as claimed in any preceding claim whose fabric is sufficiently pliable as to require the substantial support of battens stressed in similar ways.

9. A wing as claimed in any preceding claim which can be dis-assembled or stored substantially flat after use on land, or in the air or water.

10. A wing essentially as described in the foregoing text with reference to Figs 14 of the accompanying diagrams.