GB2352702A - Self launching kite with frame and inflatable canopy, eg for powered or unpowered human flight - Google Patents

Abstract

A lifting body includes a tensioned spar framework 1 supporting a sealed canopy 7 inflated to provide aerodynamic or aerostatic lift. Pilot, motor or payload are suspended by control lines 9, which assist in direction, as well as rings 10 and harness. Separate lines may be attached to trim the craft or to provide support and control in the event of breakage and the canopy 15 furthermore designed to perform even when deflated. Direct manual control may be applied by grips 11. The framework 1 may consist of spars 1 which are bound together or inserted into a torsion box (4, fig. 1) and tensioned by bow-strings 3. The double-skinned canopy 7 is then folded over the flame 1 and is joined along its trailing edge 8.

Description

2352702 SELF LAUNCHING KITE The invention relates to a kite capable of

human transport.

Vehicles similar to this kind are currently restricted to the parawing, effectively a steerable parachute, or the hang-glider which incorporates a frame from which the pilot has to be suspended.

The parawing has no intrinsic rigidity and retains its form using a series of cells filled by the airflow and a wide web of support lines to distribute the load. The hang-glider has a wing spar but being heavier it requires a pivotal framework to support the pilot and control direction.

The invention uses a spar framework to support a free-floating canopy from which the pilot or payload is suspended. It combines the advantages of the preceding aircraft in retaining the simpler operation of the parawing and the simpler construction of the hang-glider. It can also be inflated with air or lifting gas which makes it easier than each of these to launch and control.

The simplest framework to support a four-sided canopy uses as few as two members. These are continuous mainspars joined around their middle and each drawn like a bow to produce four corners to brace the craft. The payload could be suspended from each corner. The bows could be arranged fore and aft or sideways.

As an alternative to two continuous spars each of the four halves could be joined in any combination in a central torsion box which may itself be extended so that the maximum size of canopy can be stretched over a framework that dismantles to the shortest length. To prevent the sparsfrom twisting they may be supplemented by torsion spars. In fact three, four or more mainspars can be arranged in mutual tension forgoing the need for bowstrings.

The canopy or fabric can be stretched around the points of the frame as generally practised. A double-sided canopy that internalises the frame is more aerodynamically favourable especially if inflatable.

To provide the easiest interface with the framework the canopy is doublesided and sealed all round. It can be folded over the framework and joined together along one or more sides so that the leading edge occupies the told and adopts a rounded form. (Waisted or flexible spars might be applied to fabric or frame for more aerodynamic effects). The canopy may then be free-floating even in still air. It could also be reeled in or out generally at some length from the pilot on the ground, or to assist flight phases like launch, recovery, climb and descent. (it may be to use winds aloft, to augment lift or to streamline the vehicle by its close coupling).

The aircraft could be glided or pwered by a pilot and motor suspended beneath. The direction or angle of attack can be controlled by the manual transfer of weight over the lines of support or using winches. Alternatively altering the aerodynamic flow around the payload by varying the thrust for example influences the progress of the canopy too.

The lines of support may be various in number and attached to parts of the framework or canopy. There is also a variety of ways for suspending the pilot and providing control, some of which are illustrated. In each case here the pilot wears a suit or harness incorporating D-rings to which the lines are attached at the shoulders for example. This means that a powerpack may be supported by the pilot while the arms remain free to control the canopy. A motorised trike is a comfortable alternative.

1/2 Assembly of the aircraft will be clear from t he diagrams, the first of which shows how two spars (1) may be bound together (2) and drawn taught by bow-strings (3). The same arrangement can be more portably produced by the insertion of each half of each mainspar (1) into a torsion box (4) either separately or bound together and extending them for flight. This appears in Figure Two, along with torsion members (5) which may connect the mainspars (1) along the pecked line to reduce twisting. These may also be enlisted in supporting the canopy or payload.

The third diagram shows an opposing arrangement of spars (1) and bowstrings (3) to prevent distortion and here the pecked line shows how tensioners (6) may alternatively be attached elsewhere. Notice from the fourth diagram how such an arrangement of spars (1) can be made selftensioning by common termination. Three spars could be arranged like this to form a deltoid or yet more in other formats.

In Figure Five a double-skinned inflatable canopy (7) folds over the frame and joins by a fastener along its trailing edge (8) and optionally along its sides, from which the ends of each spar (1) may protrude. Figure Six shows the completed arrangement with control lines (9) and D- rings (10) to suspend the operator. Manual control bars (11) allow for rolling and pitching movement especially if the final portion of each line is elasticated.

The seventh diagram shows in profile how the number of lines (9) may be reduced to a pair which bifurcate beneath the canopy and would retain handgrips to direct it. The eighth is similar but features both a fore and an aft line (9) which could be operated independently around a pulleywheel (112) for instance.

Obvious variations to the canopy shown include division into cells or compartments such as a separate upper and lower or inner and outer section. Similarly the spars or laths comprising the members of the frame could be convexed like those in Figure Nine which here form a concertina as well. The canopies could be operated in a tandem or laddered sequence of two or more flying together.

Figures One through Four and Figure Nine show the invention in plan schematic, Figures Seven and Eight in profile schematic while Figures Five and Six are a general illustration.

The tenth diagram generally illustrates a failsafe design in which a principal pair of suspension or control lines (13) are supplemented by trim lines (14) routed nearby which may be operated independently through ring guides or pulleys to alter the flight of the lifting body formed by the tramework and canopy (not shown). Trim lines (14) appear pecked for clarity.

The effort of these adjustments may be relieved by stays like winch, motor or ratchet and any of the lines may be continuously joined to form a closed or open loop. Notice that the lines can also be arranged so that if the trim lines fail the craft reverts to a basic configuration as provided for by the primary lines of suspension (13). Conversely the degree of support provided by the trim lines (14) may be varied to a maximum, as might be required for a catastrophic failure.

In any event the suspension lines might still be equipped to act as a primary or secondary means of control, so that generally the function of the lines may be interchangeable, as is so often the case in flight control. The suspension lines (13) most influence lateral progress while use of trim lines or an alteration of thrust may as easily be applied to pitch as well.

Finally a trapeze (15) or a similar device may be included at the upper end of the lines to confine them to shoulder width for example, or as a basis for the support of other functions aloft like further payload and equipment.

2/2

Claims (8)

1 A lifting body including a fabric canopy with enclosure and means of inflation, extended over a frame and anchored to ground or payload by a pair of lines.

2. A lifting body as in Claim 1 wherein the lines are bifurcated or subdivided to provide for stability.

3. A lifting body as in Claim 1 or Claim 2 provided with aerostatic buoyancy or degree thereof.

4. A lifting body as in Claims 1-3 extended over a framework formed by joining two or more continuous or segmented spars and tensioning these where required with the canopy or bowstrings, or simply by their arrangement.

5. A lifting body as in Claim 4 formed of a cellular canopy which can be folded providing upper, lower and leading surfaces of aerodynamic form when inflated or under motion.

6. A lifting body as in any preceding claim wherein lift or direction is controlled by winching or otherwise applying forces to the lines of suspension (or to separate lines for direction or trim) whether harnessed to motor, payload or pilot and also wherein these elements may be operated at different heights from that body for purposes in flight or on the ground like streamlining or the augmentation of lift.

7. A lifting body as in any proceeding claim where safety is provided for by a canopy which continues to produce lift when deflated and a means to substitute one line of control or suspension for another in the event of breakage in flight.

8. A lifting body substantially as described here and illustrated in the diagrams.