WO2000041912A1

WO2000041912A1 - Aircraft loading and unloading vehicle

Info

Publication number: WO2000041912A1
Application number: PCT/AU2000/000013
Authority: WO
Inventors: Donald J. Mcfarlane; Carlo Dicarlo
Original assignee: Griffiths White Pty Ltd.
Priority date: 1999-01-13
Filing date: 2000-01-13
Publication date: 2000-07-20
Also published as: AUPP811499A0

Abstract

An aircraft loading and unloading vehicle (1) which includes an elongate transfer deck (2) having rollers (3) to assist transfer of objects thereunto, along or off the transfer deck (2), at least four ground engaging wheels (5) supporting the transfer deck (2) with each of the wheels (5) being substantially beneath the transfer deck (2), each of the wheels (5) being steerable, at least two of the wheels (5) being at a forward end of the vehicle (1) and at least two of the wheels (5) being at or toward a rearward end of the vehicle (1), and lifting means such that the transfer deck (2) can be lifted or lowered relative to each of wheels (5) at a forward end of the vehicle (1) and can be lifted or lowered relative to each of wheels (5) at a rearward end of the vehicle (1) so that both the elevation of the transfer deck (2) and also such that the inclination of the transfer deck (2) can be changed relative to a supporting ground surface, and a lifting platform (14) at one end of the transfer deck (2) to lift objects from a ground height to the height of the transfer deck (2).

Description

AIRCRAFT LOADING AND UNLOADING VEHICLE

TECHNICAL FIELD

This invention relates to an aircraft loading or unloading vehicle and in particular to improvements in such vehicles. Significant difficulties apply to loading or unloading of large and or heavy articles to or from aircraft.

A major application for such a vehicle relates to transfer of military equipment where the aircraft is to proceed to a remote landing field but at which there are no facilities immediately available for handling of such larger or heavier articles. Such articles can be typically conventional shipping containers or they can include individual vehicles of war and the like.

Even if an aircraft can land at a remote airfield if it is unable to effectively unload its cargo (or load), then there may be no purpose for such a trip.

Further specific difficulties apply however to such an application. Firstly, any unloading or loading vehicle must of itself be able to be transported by aircraft to the remote airfield.

Further, however, even if such a vehicle is suitable to accept and then carry heavy articles unloaded from the aircraft, it is then a matter of being able to travel across difficult terrain or sand or mud. Further, such a vehicle needs to be as simple as possible to reduce all up weight to assist for its own transfer by aircraft, and it needs to be capable of being beatable within an aircraft in such a way that it can be very accurately positioned within the aircraft so that it will not unduly impact or otherwise accidentally damage portions of the aircraft structure. An object of this invention then, is to provide an aircraft unloading or loading vehicle which at least to some extent answers some of the above problems or at the least provides the public with a useful alternative.

In one form of this invention then, there is proposed an aircraft loading and unloading vehicle which includes an elongate transfer deck having rollers to assist transfer of objects thereunto or along the transfer deck, at least four ground engaging wheels supporting the transfer deck with each of the wheels being substantially beneath the transfer deck, each of the wheels being steerable, at least two of the wheels being at a forward end of the vehicle and at least two of the wheels being at a rearward end of the vehicle, and lifting means such that the transfer deck can be lifted or lowered relative to each of wheels at a forward end of the vehicle and can be lifted or lowered relative to each of wheels at a rearward end of the vehicle so that both the elevation of the deck and the inclination of the deck can be changed relative to a supporting ground surface, a lifting platform at one end of the transfer deck to lift objects from a ground height to the height of the transfer deck, and support rollers in the platform arranged to assist transfer of objects thereunto or onto the transfer deck.

In preference there is a set of two ground engaging wheels toward the front of the vehicle at a first side of the vehicle, a set of two ground engaging wheels toward the front of the vehicle at an opposite side of the vehicle, a set of two ground engaging wheels toward the back of the vehicle at a first side of the vehicle, and a set of two ground engaging wheels toward the back of the vehicle at an opposite side of the vehicle. In preference each set of two ground engaging wheels is supported at opposite ends of a centrally pivotally supported beam.

In preference there are drive means for each of the ground engaging wheels to effect a drive of each of the wheels.

In preference, each wheel is supported so as to be steerable. In preference, the lifting platform is in the form of two parallel legs forming thereby a fork.

In preference, the lifting platform is supported so as to able to assume at least three positions, a first being a ground adjacent position, a second being an aligned position with the deck, and the third being an inclined position with an outer end of the platform being higher than its inner end.

In preference there is a control cab positionable in at least two positions, one of which is in board within an alignment of the elongate transfer deck, and in a second of the positions, offset from such an aligned position.

These and other features will be better understood when described with reference to a preferred embodiment which shall be described with reference to the accompanying illustrations wherein

Figure 1 is a perspective view of a an embodiment of the invention viewed from in front and from a side of the vehicle, Figure 2 is a perspective view of the same embodiment with the elements located in substantially the same position, the view being from an opposite side to the first view and from slightly behind the vehicle,

Figure 3 is a enlarged view in perspective of a portion of the first embodiment showing a lifting platform which in Figures 1 and 2 is in an aligned position with a transfer deck, now in an inclined storage position,

Figure 4 is a schematic view in plan of the embodiment as specifically configured and in Figures 1 and 2;

Figure 5 is a side elevation of the embodiment, Figure 6 is a front view with a control cab positioned in an offset position with respect to the side of the transfer deck,

Figure 7 is the same view as in Figure 6 except that the control cab is now located in an inboard position with a portion of the rollers of the transfer deck being repositioned to allow for the control cab position, Figure 8 is a view from the side of the lifting platform illustrating the position of the respective links and the platform when the platform is in either of two positions, where one is a ground adjacent position,

Figure 9 is a view from the side illustrating the lifting platform in an inclined position as shown in perspective detail in Figure 3, Figure 10 is a view from the side in schematic detail of a set of the wheels illustrating the way in which the wheels are supported by at opposite ends of a centrally pivotally supported beam which being itself is then pivotally supported with respect to the frame of the vehicle whereby a relative lifting of the frame can be achieved with respect to that set of wheels, Figure 11 is the same view as in Figure 10 where a lifting has been effected and this then shows the relative position of parts in a lifted position,

Figure 12 is a plan view of the arrangement of the wheels, this illustrating two sets of two wheels at a front end of the vehicle,

Figure 13 is a side view of the set of two wheels illustrating relative positioning of the respective wheels where these are being supported by a beam with a centrally located pivot,

Figure 14 is a cross-sectional view showing the coupling for a respective wheel to allow for both drive and for steering of any other wheels, Figure 15 is a schematic plan view illustrating the location of a winch and the relative position of cable and pulleys arranged so that there will be a minimum fleet angle, and

Figure 16 is a schematic view illustrating how the vehicle can be used in associated with an additional loading or unloading support.

Referring now in detail to the drawings, the vehicle 1 includes an upper-most transfer deck 2.

The transfer deck 2 has predominantly, a plurality of parallel rollers 3 which are arranged to support in a distributed manner, loads that are on the transfer deck 2 and allow these to be transferred relatively easily by rotation of the rollers 3 which will be orthogonal to the axial direction of the respective rollers 3.

The rollers 3 therefore are aligned in the embodiment in four separate tracks which extend fully the length of the deck 2 and which are distributed with even spacing across the width of the deck 2. Further, the transfer deck has sides 4 which are raised which have some advantage in limiting errant objects moving to a side of the tracks.

There are eight ground engaging wheels these being referred to generally at 5. The wheels 5 are arranged in sets of two so that there is a first set of two wheels at 6 and 7 which are toward a front and on a right hand side of the vehicle but fully beneath the transfer deck 2. In like manner, there are wheels 8 and 9 positioned on an opposite side to the wheels 6 and 7 and toward the front of the vehicle 1 and again fully beneath the transfer deck 2.

There are then a set of two wheels 10 and 11 on a right hand side of the vehicle 1 fully beneath the transfer deck 2 and toward a rear of the vehicle 1 and finally a set of two wheels 12 and 13 at a left hand side of the vehicle 1 toward the rear of the vehicle 1 and fully beneath the transfer deck 2.

Each of the wheels 5 is arranged so that it is coupled and able to be driven to provide motive force to the vehicle 1.

Further, each of the wheels 5 is supported so as to be steerable so that it will act in co-operation with the other wheels 5 to effect a drive direction of respective parts of the vehicle 1 or the vehicle 1 as a whole.

Details of the support for each of the wheels 5 and the drive mechanisms used which in this embodiment which comprise hydraulic motors will be described later.

Extending from a rear of the vehicle 1 , is a lifting platform shown generally at 14. The purpose of this platform 14 is to provide for a loading and unloading facility relative to the transfer deck 2 where other loading or unloading mechanisms may not be easily available.

It is understandable for instance, in time of trauma or other extenuating circumstances, the ability to independently handle the loading or unloading of very heavy objects from the transfer deck might become quite critical. This can especially be the case where the transfer vehicle itself is to be used to transfer heavy articles which are taken from an aircraft and then transferred to other places which might require the significant ability of the vehicle 1 to achieve access by reason of its all wheel drive system and its extensive distribution of weight by reason of the multiplicity of ground engaging wheels.

This platform 14 then is arranged in one position to be aligned with the rollers 3 of the transfer deck so that the platform which is divided into two forks 15 on the one hand and 16 on the other has in each case a plurality of rollers shown specifically at 17 in the one case and 18 in the other which allow for objects being rolled along the transfer deck 2 to be rolled onto or off from the forks 15 and 16.

However, the platform 14 has the arrangement such that the forks 15 and 16 can each be positioned in other positions and the next useful position is a lower-most position or ground engaging position as the case might be as is shown in Figure 8. In such a position, the forks 15 and 16 can be used to direct the forks into cavities within a supporting structure such as a pallet or they can be used directly to wedge beneath a shipping container and then be caused to be driven fully beneath a heavy object.

While reference has been made to "a ground engaging position" perhaps a more accurate description is a lowered position where the forks are able to be relatively moved relative to the ground to position these relative to an object.

A third position of the lifting platform is shown at Figure 9. In this case the forks shown typically at 15 are positioned in a storage position which allows for a somewhat reduced overall length of vehicle, but it also reduces an extent of swing that might otherwise be encountered when the vehicle 1 is being used with its relatively superior turning capability.

Because of the overhang, if the vehicle is turning only on its front wheels which would seem to be the worse case, then the end of the support platform when in for instance, the position as shown in Figure 2 or even when in the position as shown in Figure 8, will move significantly and in practice has been found to be potentially quite dangerous.

Smaller objects such as motor cars or even personnel can suddenly be confronted with the rapidly swinging end of the platform 14. A solution has then been to incorporate a storage position in which the outer-most end 19 is positioned somewhat higher than an inner end at 20 and in the embodiment this angle is chosen to be approximately 45 degrees to the horizontal.

This significantly reduces the difficulty described. In order to facilitate the lifting positions and the change to a storage position described, there are two linkages, a first link 21 being a lower-most link and a set of links at 22 being an upper-most set of links.

The lower-most link has a rearward most pivot coupling at 23 to a rearward upright member 24 supporting in fixed relationship the forks 15 and 16. The link 21 has at a rearward position 25 a pivot coupling to a support member 26 which is fixably supported by the vehicle 1 to a chassis of the vehicle.

The upper-most set of links 22 include 3 links which is a rearward most link 27, a middle link 28 and a forward most link 29 which has a pivotal connection at a forward most position 30 to the support member 26. A hydraulic ram 31 extends between the lower-most linkage 21 and a forward- most extension 32 of the support member 26 so that with an extension of the hydraulic ram 31 , relative pressure is placed on the linkage 21 to force it into the position as shown in dotted outline in Figure 8.

When the hydraulic ram 31 is retracted, the position returns to that shown in full outline in Figure 8.

The set of links 22 are kept extended simply by reason of the downward load, persistently on the platform and especially the forks 15 and 16, but in the event that there is an upward force on the fork 15, then the position changes to that as in Figure 9 in which the set of links at 22 pivot with respect to the others to allow for relative pivoting and therefore the assumption of the inclined position.

Such a position is achieved and then maintained by use of a chain 33 with an intermediate lift strut 34, an end hook 35 and an anchor point at 36 which is not specifically shown.

We now refer to the control cab 37. For efficient location of the vehicle 1 within an aircraft, and for use in connection with objects that are going to be carried with maximum limitations of size of such objects in relation to the aircraft, the transfer deck 2 is going to necessarily have a size which is very close to that of the carrying shape of the floor of the aircraft. This creates a difficulty with respect to the control cab and accordingly there is provided that the control cab in one position which is that for transfer by airplane, the control cab 37 is positioned inboard which is a position shown especially in Figure 7.

This is a transfer by airplane storage position but when the vehicle has been offloaded from the aircraft, the control cab 37 which is supported by manually operable slide supports 38 these allow for the cab while being maintained with its hydraulic couplings to the hydraulic controls in the vehicle 1 to be variously positioned.

The control cab 37 includes the various controls to separately control all of the hydraulic controls of the vehicle 1 which includes collectively or separately connecting each of the wheels to a common hydraulic control or drive, steering means that can ensure all of the wheels turn co-operatively or that separate wheels can be individually controlled as necessary.

In order to maintain a full supporting upper-most alignment of rollers on the transfer deck 2, there is provided a set of rollers 39 which are relocated once the cab 37 is pulled to an off-set position as in Figure 6 so that the set of rollers 39 are then located in the space left by the cab to provide the full supporting surface of rollers.

The position of the cab 37 is of significant advantage considering the application of the vehicle 1 which is to locate such a vehicle in the adjacent vicinity of an aircraft. In practice, the vehicle 1 will be located so its front 39 will be located very close to some of the elements of the aircraft so as to receive with best alignment, objects that are going to be shifted from the aircraft or of course to be loaded onto the aircraft.

By having the cab 37 very close to this position, allows a driver with great care to locate the front at 40 to be appropriately positioned without unnecessarily impacting or otherwise damaging the airframe of the aircraft.

Jacks 41 and 42 which are hydraulically operated are positioned so that when objects transfer their load from the aircraft, this will not unnecessarily cause a misalignment of the vehicle 1 with respect to the aircraft and therefore potentially unacceptable high stresses on parts of either the airframe or the vehicle 1. There are buffers at 43 which further assist in alignment especially if this is slightly misjudged.

We now refer to the wheels 5 and their support arrangements.

Each of the wheels 5 is supported for substantially horizontal motion about a pivot support at the end of a beam 44 which at its center 45 is pivotally supported at the end of a lift beam 46 which in turn at its further end 47 is pivotally supported by a member 48 which forms a part of the chassis of the vehicle 1.

A hydraulic ram 49 is positioned to be pivotally connected at an upper-most end 50 to a portion of the chassis of the vehicle 1 and the lower-end at 52 is coupled through linkage 53 to a middle portion of the beam 46.

In this way, the beam 46 acts as a stabilizer both in respect to sideways sway or to forward to aft sway.

A safety link 54 is arranged to be positionable in a safety position as shown in Figure 11 when the transfer deck itself is inner-most raised position so that a lower- end of the link 54 at 55 interlocks with cavity 56.

Steering of each of the wheels 5 is achieved by having each of the wheels independently supported about a approximately horizontally pivot support shown at 57 and 58 in the one case and 59 and 60 in the other and the control of the respective wheels 5 is then governed in each case by an arrangement of links which are most cleariy set out in Figure 12 and where there is a hydraulic ram 61 in the one case and 62 in the other which then will control the relative position of link 63 in the one case and 64 in the other from which are attached to slave from this through respective links 65 and 66 in the one case and 67 and 68 in the other that links member 69 and 70 in the one case and 71 and 72 in the other which in turn controls the relative orientation of the wheels 5 about their pivotal support.

There is a cross-coupling between the wheels on one side and the wheels on the other by linkage 73.

There is furthermore for each of the wheels 5 an hydraulic motor drive at 74.

In this way there is independent steering and drive for each of the wheels 5 and there are common couplings through hydraulic links so that the respective extensions of the hydraulic ram such as at 61 and 62 can be controlled by a central control.

The extent to which there are relative variations and extensions can be selected through appropriate control valves which are not specifically shown. The advantage of having the two wheels as a set supported by a common beam means that variation in height of ground support can be more readily compensated and allowed for.

Given the nature of the general purpose of this vehicle, an advantage is also the fact that there can be provided a single in-line wheel system which allows therefore for ready access to any of the wheels that might have been punctured for quick and easy replacement.

Further, the vehicle to some extent can support itself statically to facilitate an elevated position to assist those who might need to quickly change a tire. Figure 15 illustrates in a schematic way the location of a winch 75 which has a winch has a cable drum 76 which is positioned at one end of the vehicle 1 but which then has the cable at 77 lead through pulley 78 at the opposite end to then be diverted to where ever it is needed but in the illustrated case, there is a return pulley at 79 for cable 77 to then return to the rear end at 80. By having the cable 77 extend the full length of the vehicle 1 allows for the fleet angle off the drum 76 to be kept at a very minimal number which ensures minimal wear as cable feeds onto or off from the drum.

In an alternative arrangement, it is provided that there is a cable drum that is positioned relative to the amount of cable taken off or put back on the drum so that this then maintains the fleet angle by another way.

Figure 16 is a schematic view showing in addition to the vehicle 1 , a feed-on track

82 which separately includes a plurality of rollers so as to enable objects to be feed directly onto this and then to be able to be pulled up using the winch onto firstly the lifting platform which is shown in this drawing at 83 and then onto the transfer deck at 2.

By reason of the ability to adjust the relative height and therefore inclination of the transfer deck 2, this can then be aligned as is shown so that it will feed smoothly objects being taken from an inclined platform at 82 directly across the lifting platform

83 and onto the transfer deck 2. When on the transfer deck 2 can then be changed in orientation and of course also height so as to then match the total height to that of a loading floor of an aircraft and the platform generally can be kept horizontal as it is being used for transfer of the objects across the rollers of the transfer deck.

The result of the various features and improvements have meant that there can be provided an aircraft loading and unloading vehicle which is now able to provide for rapid and safe unloading and loading in remote areas and further able to transfer loads once unloaded over difficult terrain and in extreme conditions. Further, the vehicle itself is able to be loaded and unloaded into an aircraft very quickly and effectively. Once the problems associated with loading the vehicle into an aircraft, is that in order for the transfer deck to be effective to hold the appropriate objects that will essentially fill the aircraft, the transfer deck itself must be chosen to be of a width that is as close as possible to the width of the loading floor of the aircraft.

It will be understood however that when the vehicle itself is being loaded into the aircraft, the slightest amount of misalignment then has the potential for contacting the aircraft frame itself and potentially compromising this or of course breaking this.

Clearances of a few parts of an inch might be typical of those required in these circumstances.

For a vehicle as long as this then to have this accurately and of course quickly( considering that there might be prejudicial circumstances incurred during time of war,) accurately and quickly able to be located in the aircraft, is one of the difficulties that have been considered.

By having each of the wheels steerable, and having these each fully beneath the transfer deck itself, means that especially with independent front and rear wheel steering, the vehicle can be caused to move while maintaining a consistent alignment to a side.

Further, when the vehicle is to be aligned with its front engaging the front lip of a aircraft, it not only has to be aligned by reason of height but it also has to be aligned by reason of elongation so that for instance a shipping container being unloaded from the aircraft, will then move directly and maintain consistent alignment on the vehicle transfer deck.

Again, the ability to separately steer each of the wheels and especially these in sets in respect of both forward and aft locations enables quick and accurate alignment to be established. This is also of great advantage when using the lifting platform which might need to be located beneath goods to be shifted and where again, alignment from the start, considering that there are no such devices as cranes potentially readily available, alignment from the start is of very significant value.

Claims

CLAIMS:

1. An aircraft loading and unloading vehicle which includes an elongate transfer deck having rollers to assist transfer of objects thereunto , along or off the transfer deck, at least four ground engaging wheels supporting the transfer deck with each of the wheels being substantially beneath the transfer deck, each of the wheels being steerable , at least two of the wheels being at a forward end of the vehicle and at least two of the wheels being at or toward a rearward end of the vehicle, and lifting means such that the transfer deck can be lifted or lowered relative to each of wheels at a forward end of the vehicle and can be lifted or lowered relative to each of wheels at a rearward end of the vehicle so that both the elevation of the deck and also such that the inclination of the deck can be changed relative to a supporting ground surface, and a lifting platform at one end of the transfer deck to lift objects from a ground height to the height of the transfer deck.

2. An aircraft loading and unloading vehicle as in claim 1 further characterised in that there are support rollers in the platform arranged to assist transfer of objects there along.

3. An aircraft loading and unloading vehicle as in either one of claim 1 or 2 further characterised in that there is a set of two ground engaging wheels toward the front of the vehicle at a first side of the vehicle, a set of two ground engaging wheels toward the front of the vehicle at an opposite side of the vehicle, a set of two ground engaging wheels toward the back of the vehicle at a first side of the vehicle, and a set of two ground engaging wheels toward the back of the vehicle at an opposite side of the vehicle.

4. An aircraft loading and unloading vehicle as in the immediately preceding claim further characterised in that each set of two ground engaging wheels is supported at opposite ends of a centrally pivotally supported beam.

5. An aircraft loading and unloading vehicle as in any one of the preceding claims further characterised in that there are drive means for each of the ground engaging wheels to effect a drive of each of the wheels.

6. An aircraft loading and unloading vehicle as in any one of the preceding claims in which the lifting platform is in the form of two parallel legs.

7. An aircraft loading and unloading vehicle as in any one of the preceding claims further characterised in that the lifting platform is supported so as to able to assume at least three positions, a first being a ground adjacent position, a second being an aligned position with the transfer deck, and the third being an inclined position with an outer end of the platform being higher than its inner end.

8. An aircraft loading and unloading vehicle as in the immediately preceding claim further characterised in that to facilitate the lifting positions of the lifting platform and to change its position to a storage position, there are two linkages, a first link being a lower-most link and a set of links being an upper-most set of links.

9. An aircraft loading and unloading vehicle as in the immediately preceding claim further characterised in that the first link being the lower-most link has a rearward most pivot coupling to a rearward upright member supporting in fixed relationship forks of the lifting platform.

10. An aircraft loading and unloading vehicle as in the immediately preceding claim where the link has at a rearward position a pivot coupling to a support member which is fixably secured to a frame of the vehicle.

11.An aircraft loading and unloading vehicle as in any one of preceding claims 8 through 10 wherein the upper-most set of links include three links these being a rearward most link , a middle link and a forward most link which forward most link has a pivotal connection at a forward most position to the support member .

12. An aircraft loading and unloading vehicle as in any one of preceding claims 8 through 11 wherein there is a hydraulic ram extending between the lower-most linkage and a forward-most extension of the support member so that with an extension of the hydraulic ram , relative pressure is placed on the linkage.

13. An aircraft loading and unloading vehicle as in any one of the preceding claims further characterised in that there is a control cab positionable in at least two positions, one of which is in board within an alignment of the elongate transfer deck, and in a second of the positions, offset from such an aligned position of the transfer deck.

14. An aircraft loading and unloading vehicle as in any one of the preceding claims further characterised by having upper-most in the transfer deck a plurality of parallel rollers which are arranged to support in a distributed manner goods to be loaded or unloaded from the vehicle for transfer to or from an aircraft.

15. An aircraft loading and unloading vehicle as in the immediately preceding claim further characterised in that the rollers are arranged to be in four separate tracks which extend fully the length of the deck and which are spaced to provide support across the width of the transfer deck.

6. An aircraft loading and unloading vehicle as in any one of the preceding claims further characterised in that the transfer deck has sides which are raised to limit errant objects moving off a side of the transfer track.

17. An aircraft loading and unloading vehicle as in any one of the preceding claims further characterised in that there is a control cabin with controls for operating the vehicle which remain operable for both an inboard and offset position, which cabin is a control cabin which is adapted in one position which is that for transfer of the vehicle by airplane, to be positioned inboard which is a transfer-by- airplane storage position and by reason that the control cabin is supported by manually operable slide supports allows for the cabin to be differently positioned in an offset position.

18. An aircraft loading and unloading vehicle as in the immediately preceding claim wherein there is further provided a set of rollers which are relocatable once the cabin is pulled to an off-set so that the set of rollers can then be located to provide a full supporting surface of rollers extending fully to both ends of the vehicle.

19. An aircraft loading and unloading vehicle as in any one of the preceding claims wherein a hydraulic ram is positioned to be pivotally connected at an uppermost end to a portion of the chassis of the vehicle and a lower-most end is coupled through a linkage to a middle portion of the beam.

20. An aircraft loading and unloading vehicle as in any one of the preceding claims wherein a safety link is arranged to be positionable in a safety position when the transfer deck itself is in an upper-most raised position so that a lower-end of the link interlocks with cavity.

21.An aircraft loading and unloading vehicle as in any one of the preceding claims further characterised in that steering of each of the wheels is achieved by having each of the wheels independently supported about an approximately horizontally pivot support and the control of the respective wheels being governed in each case by an arrangement of links to a hydraulic ram which is adapted to control the relative position of link..

22. An aircraft loading and unloading vehicle as in any one of the preceding claims further characterised in that there is included a winch with a cable drum which is positioned at one end of the vehicle and has cable lead through pulley at or toward the opposite end.