-FREE FLYABLE STRUCTURE

This invention relates to flyable structures.

Broadly, according to the present invention there is provided a flyable structure including an inflatable container of such form that uhen it is inflated the container provides an aerofoil shaped cross section whereby relative displacement betueen the container and surrounding air produces lift; and substantially rigid means for supporting a load from .the contaiπer.

A second aspect of theinvention provides a flyable structure including an elongate container uhich is inflatable so as to provide a pressurised body having a leading and trailing edge region, and being capable of producing aerodynamic lift on relative displacement of the body and the surrounding air; stiffening means for maintaining at least the leading edge region of the body in a spread out condition, the stiffening means having predetermined deformation charateristics uhich are utilisable in controlling the overall shape or profile of the container during flight conditions; substantially rigid means for supporting a load from the body.

Preferably, the load support means connects, at least in part, uith the leading edge region of the body.

Conveniently,means are provided for enabling controlled changes or variations in the aerodynamic characteristics of the container to enable selective control of the flight path of the structure.

In a particular embodiment of the invention the control of the flight path is arranged. o be effected ^• by adjusting the position of the effective ueight of the load uith respect to the aerodynamic centre of lift of the structure.

Preferably, the adjustment of the ueight position is effected by displacement of the load uith respect to a mounting unit supported from the remainder of the structure.

In further embodiments facilities may be provided » for enabling pouered flight. In such cases arrangements may be made for enabling remote control αf the pouered drive for enabling local control in the case αf manned flight.

Furthermore, positionally adjustable control surfaces may be provided, for the purposes of controlling the flight path of the structure such as heading, descent , climb etc. In a particular arrangement a canard uing formation can be provided the uing formation having an adjustable setting elevator part to allou cαntol of climb and descent.

For a better understanding of the invention and to shαu hou to carry the same into effect reference uill nou be made to the accompanying drauiπgs in uhich:- Figure 1 is a schematic representation ofa flyable structure incorporating the features of the invention; Figure 2 is an end vieu of the structure of Figure 1 when the structure is aligned at a first angle of attack during flight;

Figure 3 is an end vieu of the structure of Figure 1 uhen the structure is aligned at a second angle ofattack during flight;

Figure 4 is a schematic representation of a second embodiment of a flyable structure incorporating the features of the present invention; Figure 5 is an end vieu of the structure of Figure 4 uhen the structure is aligned at said first angle of attack during flight;

Figure 6 is a front vieu of the structure of Figure 1 illustrating a position of a load relative to the remainder of the structureduring a control operation involving load displacement;

Figure 7 is a front vieu of a further embodiment of a flyable structure incorporating the features of the invention; Figures ^" 8,9,and 10 are vieus of still further embodiments of the flyable structure of the invention;

Figure 11 is a schematic side vieu of a further embodiment of the flyable structure of the invention; Figure 12 schematically illustrates a combination of structure of the invention uith a conventional aircraft; Figure 13 is a vieu of a more detailed representation of a structure of the invention, the Figure shouing the use of additional flight control arrangements.

^~ - - ^{~~ ~}

Referring nou to Figures 1 to 3 of the drawings these shou a first embodiment of a flyable structure incorporating the features of the invention; the flyable structure 1 comprising a uing formation 2.uhich comprises a generally rectangular container or envelope including a top sheet or skin 3, a bottom sheet or skin 4 uhich are connected to each other along a longer edge 5 that is to provide the trailing edge region of the container and at the ends 6 by ualls 7 uhich are shaped so as to provide an aerofoil like form to the container or body. The remaining longer edge regions 8 of the tap and bottom sheets 3 and 4 are interconnected by uay of a front uall 9 uhich provides an air inlet for ram air to enter the interior of the uing formation 2 and uhich effectively forms the leading edge region of the .uing formation.

The interior of the uing formation 2 is divided into separate cells or sub-chambers by intermediate aerofoil shaped ualls (not shown) uhich are arranged to be generally parallel to the end ualls 7. The uing formation top and bottom sheets and the intermediate ualls are generally impervious to air so that any air entering through the front uall region 9 uill pressurise that is inflate the uing formation.

The leading edge region of the uing formation is intended to be braced into a spread out condition by means αf a bracing or stiffening means 11 uhich can engage in or uith a stiffening means mounting arrangement uhich can include a sleeve for receiving the stiffening means when the latter is in the form αf a spar or the like.

The stiffening means 11 is such that it is able to flex sufficiently for the leading edge region 10 αf the

uing formation to be deformed into a predetermined curved or boued profile as seen in the direction looking from the leading edge region tα the trailing edge region of the uing formation.2. In. other uords the stiffness of the stiffening means 11 is selected such that by pulling the ends thereof touards each other the leading edge region 10 deforms into a curved shape uhich according to the deformation characteristics of the stiffening means uill either be a generally uniformly smooth deformation or a profile having a predetermined shape i.e., a relatively flat- central poration and relatively sharply curved ends. It uill be apparent that by deforming the stiffening means a corresponding shape is induced into at least the leading edge region of the uing formation.

On advancing the deformed uing formation 2 uith the leading edge region facing foruards it uill be found that even at relatively ou velocities of, for example, 4 or 5 knots the uing formation uill be inflated and thus pressurised. Because of the aerofoil form of the end ualls 7 and the intermediate ualls the uing formation uill assume an overall aerodynamic aerofoil form uhereby flou of air over the upper and louer sheets 3 and 4 uill . create the requisite force conditions for producing lift. In vieu of this aerodynamic lift property and having regard to the various forces involved in the production of lift it is a common practice in aerodynamics to presume that the effective lift forceβ can be replaced by a single lift force vector passing through a position αf the uing formation called the centre of lift.

The stiffening means.11 can conveniently be deformed into the required profile by means of lines, .stays or

'

the like 14,15 uhich are respectively attached to the ends 12 and 13 of the stiffening means 11, and uhich are themselves secured to each other or to a connection node or to any other suitable location means. Since it is required that the uing formation should carry a load 17, for the purposes of the description in connection ui h Figures 1 to 3, this load uill be regarded as being connected to the node 16, i.e., effectively to the joint betueen the lines 14 and 15. As so far described it uill be noted that the load is symmetrically supported uith respect to the leading edge region 10 of the uing formation 2. In other uords the resultant vertical force component of the load 17 uill pass through the line of symmetry of the uing formation 2 i.e., the geometrical centre 18 of the leading edge region. Also since the load is suspended beneath the uing formation 2 the effective centre of gravity αf the flyable structure uill be located at a point beneath the centre of lift αf the uing formation 2. In this specification the term effective centre of gravity is intended to represent the effective centre of the vertical force components acting in a dounuardly direction, i.e., ueight of the load, and uing formation and the like. A particular characteristic of the flyable structure of the invention is that the principal ueight or load of the structure uill normally be connected to the leading edge region 10 of the uing formation, and that any relative displacement of the effective centre of gravity relative to the centre αf lift provides a flight direction control parameter.

OMPI

-~:r -•-..----_, ,____._, >

-7-

Fαr practical purposes it is convenient to consider that the leading edge region extends from the actual leading edge back touards the trailing edge region for approximately one third of the distance betueen leading and trailing edges -of the container 2.

Referring once more to Figure 1, uith a vieu to setting positively the maximum distance of the load from the central region 18 of the leading edge region 10, the the load 17 is connected to the suspension region by uay of a strut uhich is at least semi-rigid or similar member 19. It uill be understood that this strut serves to transmit at least a part αf the load forces to the uing formation 2.

Figure 2 schematically illustrates a side vieu of the structure of Figure 1 uhen the uing formation thereof is in a levol flight condition or attitude.

Figure 3 schematically illustrates the structure of Figure 1 and of Figure 2 uhen the uing formation is set set at an angle of attack characteristic of a glide type of flight condition.

In order to arrive at the orientation shoun the forces acting upon the uing formation, i.e., lift, drag, load ueight, nature of the load, speed etc., have caused the uing formation to self adjust to the optimum conditions in that the resultant force vector is along, that is contained in, a vertical plane including the lines 14 and 14. It should be noted that this condition does not necessarily imply that the line or strut 19 is vertical. In other words the flight angle or angle of attack of the uing formation automatically adjusts itself to accomαdate the overall effects of the various forces acting thereupon.

-a-

Referring now to Figures 4 and 5, these schematically illustrate in a highly simplified form a flyable structure uhich is pouer propelled by a prαpellαr 20 driven from a motor 21 uhich is supported from the leading edge region 10 of the uing formation 2 by uay of a support arrangement such as a group of sup-port lines 22 uhich are so connected that the mαtor 21 is set to a generally horizontal setting, and uhich is such that a vertical strut 23 connecting uith the centre 18 of the leading* edge region connects essentially uith the centre of gravity of the motor 21.

In operation, it is believed that, assuming that any air flou over the uing formation is from left to right of the Figure, the overall resultant of the various forces acting upon the flyable structure, i.e., the force couple arising from the horizontal components of thrust at engine level, uing formation drag, the ueight of the load, the lift forces, the angle of attack and so forth uill cause the uing formation to set into a particular ^• angle of attack uhich uill vary according to the force resultant and the nature of the various farces forming the resultant.

So far the sole reference to the matter of directional steering of the flyable structure has been limited αr restricted to the suggestion that steering can be controlled according to the relative position of the ueight or load uith respect to the vertical plane containing the centre of lift or leading edge region αf the uing formation. Other possibilities uill be mentioned hereinafter. However, in so far as weight position adjustment is concerned the control αf steering by this method uill be briefly examined in relation to

Figure 6 uhich can conveniently be regarded as a front viau of the arrangements αf Figures 1 to 3 uith, houever, the addition of means 24 at the connection node 16 for enabling relative displacement of the load with respect to the vertical plane containing the centre 18 of the container leading edge region 10.

In a simple embodiment the means 24 can be regarded as a pulley unit 25 around uhich the lines 14 and 15 are urapped such that rotation of the pulley unit 25 produces a shortening of one of the lines 14,15 simultaneously uith an increase in the length of the other one of the lines 14,15. In other uords, the portions of the lines 14,15 on the pulley are urapped capstan fashion. The pulley unit may be controlled in any suitable manner i.e., motor driven by a remotely controllable motor (not shoun in Figures 4 _^ and 5)

On operating the pulley unit 25 the load is effectively displaced to one side or the other side of the vertical plane containing the centre 18 of the uing formation leading edge region 10. This has the effect of so adjusting the relative settings of the lines 14 and 15 and the strut 19 uith respect to the vertical plane previously mentioned that tension components are induced into the lines 14,15 and the strut 19 uhich are unbalanced or asymmetric as compared to the tensions prevailing prior to the displacement of the load and uhich so act upon the stiffening means 11 as to change the deformation shape αf the stiffening means and thus a corresponding change in the shape of the uing formation. This i n turn causes a resultant variation in the lift forces acting upon the wing formation and thus a change

iπ the flight conditions.

Uith the position as shown in Figure 6 the result of the displacement of the load 17 into the position shoun is that the lift forces acting upon the uing formation to the right of the vertical plane containing the centre of gravity of the load are greater than those acting to the left of said plane.

Consequently, the uing formation uill tend to move touards the left thereby changing a straight flight path to a flight path along a further direction.

Clearly, a displacement of the load in the reverse sense uill produce a directional change in the opposite direction.

Turning now to a second important mode of controlling the flight path of the flyable structure namely, causing the structure to clim-b or descend; this control function can in general terras be effected by changing the position of the load centre of gravity uith respect to the uing formation along the fore and aft direction of the uing formation. This load position variation, in practice, adjusts the angle of attack of the wing formation 2.

This load position adjustment can be conveniently effected by mounting the load for position displacement along a track arrangement (not shoun) extending in the fore and aft direction of the uing formation, and by providing, for example, motorised means (not shoun) uhich can be remotely controlled for controlling the displacement.

Referring πou to Figure 7 in the embodiment of this Figure the central strut 19 discussed in relation to previous Figures is replaced by a frame arrangement 26

__OVPI

including tuo struts 27,28 interconnected at their louer ends at the connection node 16 and whose upper ends 27A and 28A connect uith the leading edge region 10 at tuo locations 29 and 30 spaced to either side of the uing formation leading edge region centre 18. The locations, 29, 30 effectively define a central portion 31 to the uing formation uhich is substantially rigid, i.e., flexure of the leading edge stiffening means 11 is at least substantially prevented betueen the connection locations 29 and 30 uhereby all operative control of the flight flexure takes place in the portions 31 and 33 of the uing formation to either side of the strut connections 29 and 30.

In other uords the effect of the shortening and lengthening αf the lines 14 and 15 as a result of operation of the pully unit 25 is to deflect the portions 32 and 33 relative to the central portion.

As uill be seen from Figure 7 the flight directional movement pulley unit 25 is located in the vicinity of the connection betueen the louer ends of the struts 27 and 28. It uill be clear that thedirectional control pulley unit is positiαnally fixed distance wise uith respect to the central section 31 by the struts 27 and 28 so that any operation of the pulley unit is such as to cause < immediate relative displacement of the uing formation end portions 32 and 33 uith respect to the central portion 31.

The load 17 to be carried is mounted to the underside of the strut connection node 16 and since, as previously mentioned, positional movement of the load in the fore and aft directions provides a control parameter or function for the variation of the angle of attack of the wing formation 2 during flight arrangements are made far

enabling the requisite selective positional adjustment.

Turning now to the arrangement of Figure 8 in this embodiment the generally inverted triangular strut arrangement of Figure 7 is replaced by a quadrant system 34 comprising tuo side parts 35 and 36 forming struts of the flyable structure and a curved, i.e., part circular, base part 37 uhich is directed generally in the fore and aft direction of the wing formation 2.

The load 17 is supported from the quadrant base part 37. The connection betueen the load and the base part 37 can be such as to allou relative movement along the length of the quadrant base part.

The upper end of the quadrant system 34 is connected to the central region 18 of the leading edge region 10. The connection is such that the whole uing formation can pivot about an axis generally aligned in said fore and aft direction relative to the quadrant system. If desired, this connection can compelsβ a universal form of pivot to enable relative movement in any direction uith respect to the uing formation.

A further possibility is that the connection is not a pivotal connection so that the flight control uouid reflect the condition of the uholeuing formation being subjected tα flexure change. The tie lines 14 and 15 for the end regions αf the uing formation leading edge are connected to the quadrant base 37 at the point 38. Conveniently, the connection uill include a pulley unit 25 uhereby the end regions of the uing formation can be positiαnally controlled with respect to the quadrant to effect directional change.

It uill be appreciated that since the quadrant system 3'4 carries the load 17, and since this load uill provide

- 13-

the greater part of the weight αf the flyable structure any operation of the pulley unit 25 uill produce a corresponding change in the shape of the uing formation and can be positionally controlled uith respect to the quadrant tα effect directional steerage of the structure. Various possibilities for the adjustments to the effective lengths of the lines uill be considered hereinafter. For example, actual change in length or displacement of the node 16 from a position immediately beneath the centre 18 of the leading edge uhich may be regarded as displacing the load relative to the uing.

It uill be appreciated that in a construction in uhich the quadrant system is fixed (i.e., not pivoted) uith respect to the uing formation the adjustments to the lines 14 and 15 uill mainly deflect the end regions of the uing formation relative to the remainder of the uing formation.

For the purposes of adjusting the angle of attack it is possible to vary the fore and aft position αf the load as discussed hereinbefore. Houever, the provision of the quadrant makes it possible to introduce a further mode of varying the angle of attack. In this second mode the position' of the attachment point 38 is arranged to be selectively displaceable lengthwise αf the quadrant base 37. Such displacement may be made by manual or motorised controls. In the latter case remote control arrangements may be provided for the control of the motor during flight.

It uill be appreciated that in the case of manned flight the load would include the weight of the user (s), and that such manned flight can be power or non-power driven.

OMPI

Figure 9 schematically shαus hou the structure of Figures 1 to 3 may be modified to* enable manned flight.

In the Figure 9 arrangement a space frame unit 40 replaces the strut 19, the unit 40 including a base section 41 connected to the central region 18 of the leading edge region 10 by uay of the upper ends 42 and 43 αf bars 44 and 45. The base section 41 comprises a generally U-shaped element 46 including a base 47 and tuo arms or limbs 48. The limbs 48 are connected to the louer ends 49 and 50 of the bars 44 and 45. The frame unit 40 is supported from the uing formation by tuo pairs αf lines or struts 51 and 52 in such manner that the base 47 forms the leading part of the unit 40 uith the limbs directed rearuardly, and also such that the frame unit lies substantially horizontaluhen the uing formation is symmetrically positioned uith respect to the horizontal.

The connection betueen the bars 44 and 45 and the base section 41 can be such that uhen the plane αf the unit is horizontal the bars 44 and 45 lie in a vertical plane, or alternatively the bars may be inclined to the vertical .plane in a rearuardly direction so that the leading edge region 10 of the uing formation 2 is positioned to the rear of the leading part of the frame unit 40.

A user support harness or the like 53 is suspended from the upper end regions of the bars 44 and 45 or other location closely adjacent thereto by a mounting shackle arrangement 54. The positioning and form of the harness can be such that the user is suspended in a manner similar to the user αf the so-called 'Hang Glider' and such that he is able readily to grasp the

limbs 48 to use them as a means uhe eby he is able readily to displace his ueight relative to the uing formation 2 in selected directions fore and aft and transversely of the fore and aft direction of the uing formation, for the purposes of controlling the flight of the flyable structure.

In practice, by adjusting his ueight in the fore and aft direction the user can selectively alter the angle of attack, and by adjusting his ueight in the 3ide-to-side direction relative to the central vertical plane of the uing formation that latter is cause to turn to the required direction.

It uill be appreciated that during an actual flight the user uill be making various combinations of ueight displacement movements so that,in practice, the uing formation may uell be subjected to a relatively complex group of farces, deformations αr distortions uhich lead to the required relative movement betueen the load and uing formation. Referring πou to Figure 10, the frame unit essentially comprises a rectangular portion 55 including struts 56,57,58,and 59. ^' Struts 60,61,62 and 63 are connected as shoun to the corner regions of the portions 55 and also at their other ends to a common connection point or node 64. Conveniently, the end regions of the louer strut 58 and the struts node 64 can be used for the mounting of road running uheels 65,66 and 67 to . thereby provide the facility of an aircraft undercarriage It uill be noted that the struts 58,60 and 61 uill thus be in a horizontal plane.

The rectangular frame 55 lies in a plane uhich is tilted fαruardly uith respect to the vertical so that

-16-

the upper strut 56 is located intermediate the lengths of the struts 60-63.

The leading edge region 10 is connected by uay of pivot connections 68 and 69 to the upper corners αf the frame 55. The lines 14 and 15 connect the end regions of the uing formation leading edge and the stiffening means 11 to a connection position 16A at a location lying in the vertical plane including the lines connections and pivot connections 68 and 69 uhilst the uing formation set for straight flight.

A user seat unit 70 is mounted from the struts so as to be generally in the plane containing the leading edge region 10.

As has been previously discussed the directional control is effected by the relative displacement of the junction of the lines 14 and 15 to produce the relative flexure of the end portions of the uing formation. This displacement can be by means of a joy-stick system (not shoun) uhich is arranged to be able to produce the requisite displacement for directional control and also the fore and aft movement for the purposes of varying the angle αf attack.

Referring now to Figure 11 this illustrates a modification of the structure shoun in Figure 10. In Figure 11 additional struts uhich extend to the rear of the previously described frameuotk 55 are used to mount positioπally adjustable flight control surfaces. Thus the embodiment includes additional struts 71 and 72 uhich carry a support 73 for a rudder and elevator 75. Control lines 76 (only one shoun) are provided for enabling selective movement of the control surfaces.

These control lines 76 connect uith the conventional joy-stick system for the elevator and rudder bar or the like for the rudder. Alternatively the coπttαl arrangement may include a canard uing arrangement. It uill be understood that any motor drive uill be capable of variable speed adjustment.

Furthermore, it uill be appreciated that the control of the control surfaces and the motor speed variation can be effected by remote operation such as by radio control. It uill be noted from the above discussions that a major factor in the control of the flight of the flyable structure is be the effective selective displacement of the centre of gravity of the structure's load relative to the centre of lift and that such control can be augmented or replaced by, under certain situations, the provision of additional control surfaces uhich are positioned at suitable ( in aerodynamic terms ) locations uith respect to the leading edge region 10 of the uing formation. It uill also be appreciated that a matter αf importance is the ability of the stiffening means 11 to maintain the sheets of the uing formation in the required extended aerofoil condition.

A further application of the flyable structure of the invention, and particularly of the embodiment of Figures 1 to 3 is to the creation of extra lift to a conventional fixed rigid uinged aircraft by, in effect, mounting the flyable structure of the present invention in a pick - back arrangement uith the uings of the conventional aircraft, uhereby the latter acts as the load for the uing formation and thus the flyable structure. Uith this arrangement additional lift is provided at the take-off period of the conventional aircraft. After

a desired height has been attained the structure of the invention is jettisoned. This concept is very schematically shoun in Figure 12.

Referring πou to Figure 13, this schematically shous a flyable structure comprising a radio controllable prαpellor driven aircraft. In the structure shoun the load 17 may be considered to incorporate, as uill be discussed hereinafter, a motor drive unit, remotely operable control arrangements for the motor drive unit and any other components involved in the construction plus any 'pay-load' i.e., the user of a structure in the case of a manned flight.

For convenience those components that have previously been specifically identified uith reference numerals in previous Figures uill be identified by the same references in Figure 13.

Thus in Figure 13, the structure shoun therein incorporates the uing formation 2 and associated stiffening means 11, the lines 14,15 and the king post 19. The king post is is pivotally connected at its upper end 19A to the central rgion 18 of the container leading edge region 10, and at its louer end 19B to the load 17. The load is regarded as including a main frame section 80 uhich serves to mount the drive arrangements of the structure (to be discussed hereinafter), a foruardly directed main spar 81 carrying at its fαruard end a canard uing assembly 82 and the above mentioned 'pay-load' uhich in the Figure is very schematically shoun as a housing 83, for enclosing the main spar structure and for providing a simulated cock-pit region.

The drive drive arrangement for the flyable structure basically includes a power unit 84 including a liquid

CMPI

fueled internal combustion engine 85 driving a propeller 86 operating in pusher mode. In the arrangement shoun the fuel tank 87 for the pouer unit is mounted tothe top of the main frame. The conventionally provided fuel lines are not shoun in the Figure. The pouer unit is of a variable speed and is controlled by a throttle control servo unit (not shoun) uhich is in turn controlled by a radio control unit including a radio receiver/transmitter unit and associated power supplies (not shoun) The radio control unit and servo units are mounted to the main frame.

In the arrangement of Figure 13 the previously mentioned control means 24 includes a second strut or like element 87 uhich is pivotally connected to the upper end 19A of the king post 19 and at its lower end 87B to the free end of a lever 88 pivotally movable about an axis substantially parallel to that of the king post 19 the lever 88 being suingable about its axis under the control of a servo control element 89 included in the structure control arrangements and mounted to the main frame section 80.

This servo control unit is under the operational control of the radio control unit. Far convenience, the operation αf the lever 88 and the associated servo unit 89 are externally mounted to the main frame.

The ends of the lines 14,15 also connect uith the end of the lever 88 uhereby the latter point of connection forms the previously mentioned node 26 so that the pivotal displacement of the lever 88 produces a displacement of the node uith respect to the main frame section 80 and thus the remainder of the load. Consequently, upon movement of the lever 88

pull is exerted on one or the other of the lines 14 and 15 uhereby the container tilts uith respect to the king post 19 according to the direction of displacement of the lever 88 about the king post uith the extent of tilt related to the extent of pivotal movement of the lever 88.

The canard uing assembly 90 includes an elevator surface 91 and a poβitionally adjustable control surface 92 uhose angular setting to the horizontal controls the climb and descent of the flyable structure. The elevator surface connects uith a control lever or the like 93 uhich is selectively movable by uay of a control connection 94 with a control servo unit ( ^r πot shoun) mounted to the main frame and operable by the radio control unit. The structure is mounted upon a nose uheel 95 steerably connected uith the leading edge of the main spar 81 and fixed uheels 96 carried by mounting struts 97 extending from each side of the main frame. The steering of the front uheel is effected by uay of a control linkage uhich couples the nose uheel movements to the movements of the lever 88. This particular control is particularly utilised during taxiing of the flyable structure.

It uill be understood from the above discussion that the container needs to be made from a material uhich enables the flexing of the container during use and uhich will also enable the selection of a desired flight profile. For small aircraft for example wing spans of 1 to IQmetres a material commonly known as Rip Stop Nylon has been considered suitable. (Nylon is a

Registered T _r ade Mark). Other materials exhibiting

OMPI

corresponding strength, flexibility and imperviousness to passage of air may be used.

If it is desired to increase the overall lift it is possible to use one or more additional uing formations uhich is or are arranged in stacked formation above the wing formation actually coupled to the king post. Any such additional uing formations would be attached by uay of connections between the end regions of the stiffening means αf successive uing formations. Uith this arrangement any such additional uing formations uill be caused to move uith, i.e., displace, flex or the like uith the uing formation attached to the king poet and lines 14,15. If desired the lines 14 and 15 may me extended so as to be connectable to the stiffening means of all of the uing formations used.

From the above it uill be seen that the invention provides a free flyable structure in uhich the uing formation, the king post and the load provide uhat is essentially a composite construction in that the uing formation is maintained at the leading edge region thereof at a predetermined distance auay from the load, uhereby the leading edge region cannot collapse touards the load. Bearing in mind the use of the propeller 86 a support bracket 98 is provided for holding the trailing edge regions of the container or containers auay from the propeller uhilst it is in a preflight collapsed condition in the case of ram air fillable i.e., pressurisable containers.