The delivery of supplies, often of food or other goods, by the simple dropping of such a load from an aircraft carries many advantages. In recent times, it has been used very frequently in the deployment of aid packages containing food or medical supplies and the like, by military and charity organisations assisting in emergency situations. Such means of load deployment may also, however, be successfully used in delivery by commercial aviators.

Damage to the load may, in some cases, be caused when released, particularly if such release has not been in a controlled manner. Uncontrolled release of the load may result in considerable damage to the load, and also damage and/or considerable danger to any people or constructions close to the delivery site. It is imperative, then, that means for securing the load supporting platform to the aircraft should be reliable in terms of securing the load and in terms of rapid and controlled release of the load when required.

Many of the load-supporting aerial delivery platforms currently available incorporate an assembly, arranged parallel to the plane of the load supporting platform, for securing the platform to the body of an aircraft. Retraction of such stops, by rotation about a vertical axis, results in release of the load supporting platform. One problem with such vertically-disposed stops is that any failure to fully retract such stopping means would provide an obstacle to free release of the load and/or any further load supporting platforms.

In this way, the load and load supporting platform may be entirely restrained within the aircraft or, in the case of failure of a single such stopping means, only partially so. This may further result in balance problems for the aircraft, and eventually total breakage of part of the assembly.

Aerial delivery platforms claimed in the prior art often comprise a complex array of components for the securing of the load supporting platform or platforms. In US 2 774 560, to Lockheed Aircraft Corporation, there is shown an intricate assembly including a latch pawl, latch member, and a series of linkages and control arms.

A further type of currently available prior art aerial delivery system comprises a buffer-type arrangement for restraining the load when installed within he aircraft. Essentially, these comprise a platform provided with a vertical restrain member with a support member secured to the restrain member and the platform to provide a brace. Disadvantageous aspects of this type of arrangement include the necessity for a frame to be further provided, in order to mount the buffer and stays; such a structure may take up large amounts of useful space within the hold of an aircraft.

The advantages of a simpler and smaller construction are intuitive; they bring cheaper production costs and ease of installation, as well as a smaller number of parts to maintain.

An object of the present invention is to provide an aerial delivery platform which comprises a simply constructed load restraining means for forward restraint of the load.

The present invention and its preferred embodiments seek to overcome or at least mitigate the problems of the prior art.

A first aspect of the present invention provides a forward restraint apparatus for restraining a load in an aerial delivery system comprising restraining means to provide forward restraint to a load, which restraining means is pivotally connected to a support body to be displaced between an operative position extending upwardly from the support body, and a retracted position substantially coplanar with the roller tray.

An object of the present invention is to mitigate the above problems by offering an assembly comprising a restraint means retractable about a laterally-orientated folding axis, perpendicular to the plane of the load supporting platform.

Such an arrangement may further be considered advantageous in the use of multiple load supporting systems. In such a situation, after release of the first load supporting platform from an aircraft, subsequent load supporting platforms may simply strike the restraining

means into a position perpendicular to the plane of the load supporting platforms, to allow release of the load and its supporting platform.

Beneficially, the aerial delivery system comprises means for longitudinal displacement of the load supporting platform when installed in an aircraft, so as to accommodate deviations in platform shape.

Preferably the restraining means may be moveable within the support body to adjust the position of the restraining means.

Optionally the restraining means may be longitudinally adjustable by adjustment means.

Preferably, the adjustment means may comprise a mounting block for mounting the restraining means and a threaded collar and corresponding rod secured to the mounting block, which collar may be rotatably moveable relative the rod to impart linear movement to the rod in a longitudinal axis and wherein the rod may be secured to the mounting block. More preferably the movement of the mounting block may be guided by guide means. Even more preferably, the guide means may comprise a guide track formed in the support body and corresponding flanges formed in the mounting block which flanges are received in the guide track.

According to an optional feature of this aspect of the present invention, the collar may be restricted from inadvertent movement by an engagement device to maintain the desired position of the restraining means. Preferably engagement device may comprise a spring and ball detent mounted in the outer support body.

According to a second optional feature of this aspect of the present invention the restraining means may comprise a restraining member pivotally connected to the mounting block.

Preferably said aerial delivery system may further comprise a visual indication apparatus to show the deployed or retracted state of the restraining member. More preferably said visual indication apparatus may be provided at the fore end of the aerial delivery system.

A second aspect of the present invention provides an aerial delivery system comprising one or more roller trays secured to the aircraft floor, which roller tray accommodates a series of one or more rollers, to assist in moving a load on said roller trays and a forward restraint

apparatus mounted to the roller tray. The roller tray or sandwich panel mounts both the roller and the estraing means, so as to allow the combined structure to carry large fore/aft loads.

Preferably, said roller trays may be constructed to be used on port or starboard sides of the aerial delivery system. Optionally the aerial delivery system may be so constructed and arranged as to accommodate a single load supporting platform. Alternatively the aerial delivery system may be arranged as to accommodate multiple load supporting platforms. A further preferred feature of the present invention provides the use of a sandwich panel to mount both the rollers and the stop; such an arrangement allows the structure to carry large loads from the stop to floor pickup points.

According to an optional feature of this aspect of the present invention each roller may be rotatably mounted to roller mounting means which mounting means is attached to the roller tray. Preferably said roller mounting means may be accommodated by a recess in the roller tray, said recess being of a shape complimentary to the underside of the roller mounting means. More preferably said roller mounting means may be secured into said recess by securing means. Even more preferably said securing means may be an epoxy resin adhesive.

According to a further optional feature of this aspect of the present invention said roller trays may be constructed of aluminium-skinned composite board. Preferably said aluminium- skinned composite board may have a"honeycomb"appearance in cross-section.

A further object of the present invention provides an aerial delivery system comprising a roller tray for use in multiple load supporting platform assemblies.

Exemplary non-limiting embodiments of the present invention, will now be described, by way of example only with reference to the accompanying drawings, in which: FIGURE 1 is a perspective view of an aerial delivery system for attachment onto the floor of an aircraft; FIGURE 2 is a perspective view of an aerial delivery system assembled so as to accommodate more than one load supporting platform;

FIGURE 3 is a perspective view of a roller tray with load restraining means mounted in a mounting block thereupon; FIGURES 4A and 4B are perspective views of load restraining means according to one embodiment of the invention; FIGURE 4C is a cross section of the same apparatus as shown in Figures 4A and 4B; FIGURE 5 is a roller tray in plan view, side view and underneath view, without the rollers secured therein; and FIGURES 6A and 6B are perspective views of the roller mounting means.

As is best seen in Figures 1 and 2, one aspect of the invention comprises a series of one or more roller trays 12; In this embodiment, each tray 12 has an approximately rectangular form, along one side of which is connected a series of roller mounting means 14, disposed in an arrangement approximately parallel to one another, and approximately perpendicular to the same edge of the roller tray 12. Rollers 32 are mounted in the roller mounting means 14.

Further attached to each roller tray 12 is a load restraining means 16 for restraining a load, for example a platform P.

The load restraining means 16 is illustrated in more detail in Figures 4A, 4B and 4C and is provided with a support body 17. The support body 17 is secured to the roller tray by suitable securing means known in the art. In the illustrated embodiment, the support body 17 is bolted to the roller tray 12 (shown in Figure 1).

The support body 17 accommodates a restraining member 18 which is pivotally connected to a mounting block 22 by an axle pin 38, thereby allowing movement of the restraining member 18 from an arrangement approximately perpendicular to the body of the support body 17 to an arrangement approximately coplanar to the support body 17, and vice versa. In use, the folding axis of the restraining member is in a lateral plane (i. e. normal to the direction of travel of the platform). Thus, a second platform will knock down the forward restraining member for the first platform to allow passage therethrough thereby allowing any further load-supporting platforms to fall freely from the aerial delivery system 10. Such an

arrangement may be seen to be advantageous in that it decreases the likelihood of jamming of the aerial delivery system 10 within the aircraft.

The mounting block 22 is moveable relative the support body 17 so as to reposition the restraining member 18.

Preferably, there comprises guide means 21 to guide the mounting block with respect to the support body 17. In this embodiment, the guide means is provided by opposed flanges 24 extending outwardly from the sides of the mounting block 22. The flanges 24 are received in corresponding recesses (or guide tracks) 26 formed in the support body 17. The flanges 24 are moveable within the recess so as to permit longitudinal movement of the mounting block 22 within guide tracks 26. The guide tracks 26 are co-planar within the support body 17.

In order to move the mounting block 22 in a controlled manner suitable control means is provided, for example a rod-and-collar assembly 20. In this embodiment, the assembly 30 comprises a threaded collar 28 and corresponding rod 30 which passes through the collar 28, shown in Figure 4C. The rod 30 is mounted in the sliding block 22 and is prevented from rotating by suitable securing means, for example a screw 31. The rod 30 passes through the support body 17 and the collar 28. In order to effect longitudinal movement of the mounting block 22 within the guide tracks 26, in the directions Y, a collar portion 28 of the rod-and- collar assembly 20 is rotated in the directions X. Such rotary adjustment in the directions X of the collar portion 28 of the rod-and-collar apparatus 20 effects a linear motion of the rod portion 30 by the threaded engagement. This in turn causes movement of the restraining member 18, mounted on the mounting block 22, in the directions Y. Preferably, limit stops 29 are provided to prevent removal of the mounting block 22 from the ends of the guide track 26. Similarly, suitable limit stops 31, for example a compression spring, limits movement of the mounting block 22 in the opposite direction.

In the preferred embodiment, the collar 28 is provided in a recess of the support body 16 so as not to protrude above the support body, which is undesirable.

According to one embodiment of the present invention, the rod-and-collar apparatus 20 may further comprise, within its collar portion 28, engaging means, for example one or more spring and ball detents 42, provided in the support body 17 to engage corresponding recesses

44 in the collar 28 which engaging means prevents accidental adjustment of the rod-and- collar apparatus 20 from being caused by vibrations when the aircraft is in motion. This allows the desired position of the load restraining means 16 to be safely maintained in use.

Similarly suitable engaging means, such as spring and ball detents 42 are provided along sides of the restraining member 18 to be engaged in recesses 44 in the mounting block 22 to similarly restrict the movement of the restraining member between operative and retracted positions.

A further optional feature of the illustrated embodiment provides a means for improving the visibility of the system. The attachment of a suitable indicator means to the restraining plate 18 may be employed in order to achieve this. One such means is achieved by the provision of a piece of luminescent material on the forward edge of the restraining plate 18. In such an arrangement, if the restraining plate is correctly positioned, then the luminescent material will be clearly visible; conversely, if the restraining plate 18 were to be down, and the platform in place, the material would be obscured, and so not visible. Alternative methods of achieving such indicator means include the use of an electrical indication system employing a series of one or more microswitches adjacent to the or each restraining plate 18. A further alternative method provides the use of load cells in each stop to check that it is properly adjusted.

Turning again to the construction of the roller trays 12 with reference to Figures 1,2, 3 and 5, roller tray 12 includes, in each of its series of roller mounting means 14, a roller 32. The roller 32 is of approximately cylindrical form, and has a shaft section 34 in each circular face.

The roller mounting means 14 shown in Figure 6 is so constructed and arranged as to accommodate the shaft sections 34 in such a way that rotation of the roller 32 about the shaft sections 34 is permitted. This feature of the embodiment of the present invention improves the loading and unloading of a platform load onto and from the aerial delivery system. Each roller mounting means 14 is fixed to the roller tray 12 by the insertion of the lower portion 36 (Figure 6) of each roller mounting means 14 into recessed regions 39 on the roller tray 12. It is envisaged that these roller mounting means 14 may be secured in place by adhesive means, such as application of an epoxy/diamide resin.

In a preferred embodiment the aerial delivery system 10 may preferably comprise one or more roller trays 12 on each of which is mounted a series of roller 32 within roller mounting

means 14, so constructed and arranged as to allow easier loading of a load onto said aerial delivery system 10, for example shown in Figure 2.

A further aspect of the preferred embodiment of the present invention is that the roller tray 12 is so constructed and arranged as to allow application of that said roller tray 12 to either port or starboard sides of the aircraft delivery system 10. This is achieved by the roller tray 12 being a uniform size and the roller mounting means 14 are attached to the tray in an offset arrangement shown in Figure 3 and in use in Figure 2. This is clearly a beneficial feature, as it reduces production/manufacture costs, by allowing production of a greater number of identical parts; it further eliminates the possibility of confusion when an aerial delivery system 10 is passed onto a consumer;"the wrong roller tray 12"cannot be provided in error, as the roller tray 12, according to this embodiment of the invention, is applicable to port and starboard sides, and also to single-load-supporting platform or multiple-platform aerial delivery systems 10.

It is envisaged according to an embodiment of the present invention that the roller tray 12 will be bolted to the aircraft body.

Construction of the restraining means 18, the guide means 16 and the mounting block 22, is preferably of aluminium alloy, though it need not necessarily be limited to this. Further, it is envisaged that the rod-and-collar apparatus 20 should preferably be constructed of steel, though it need not be limited to this within the scope of the present invention.

It is yet further envisaged that the roller tray 12 should be constructed of aluminium composite board. According to one embodiment of the present invention, this aluminium composite board has a"honeycomb"appearance in cross-section; a further aspect provides for an aluminium coating of said board material.

It should be understood, however, that within the scope of the present invention, the construction of the aforementioned parts and fittings to the present invention need not be limited to those materials herein described, but that these merely indicate the envisaged preferences.

It should further be understood that terms of direction used herein, such as"longitudinal", "lateral", "side"and"end"are merely used for convenience, so as to distinguish the various parts and fittings within the present invention. They do not limit the apparatus to which they are assigned to those particular orientations. Further still, it should be understood that numerous changes may be made within the scope of the present invention, for example, by the use of other known adhesive and/or securing methods.