Field of the Invention

This invention relates to a device for parking aircraft, in particular, but not exclusively to a device for parking light aircraft.

Background to the Invention

An operator/owner of a light aircraft is faced with the problem of where to store the aircraft when not in use. It is often the case that hanger space is not available or is expensive. Very often an aircraft of this type spends most of its life on a grass meadow adjacent to the runway exposed to winds from any direction. Under certain circumstances these winds can cause severe damage to the aircraft.

Most small aircraft will start to fly at speeds in excess of 50 m.p.h (some at a lot less). This means that a wind gusting to say 60 m.p.h is likely to raise the aircraft into the air then drop it several feet when the gust drops below flying speed, the consequence being a very large repair bill. To prevent this, aircraft should be tied down to a solid anchor, which generally means concrete blocks or other weighty objects.

As well as being damaged by dropping, an aircraft can sustain damage as a result of high winds blowing at the aircraft from a direction that it is not designed to cope with i.e not from the front. Damage can occur to the

rudder and elevator systems very easily. To overcome this risk, the aircraft has to be turned into the wind when parked thus requiring the operator to physically manoeuvre the plane and the tie down blocks every time that the wind changes direction and when it is reasonably strong.

This can be a major problem if the owner is away from his aircraft when the wind blows up unexpectedly or for an operator in charge of an airfield where many planes are stored and he/she may be unable to respond quickly enough to a change of wind speed/direction.

The object of the present invention is to reduce or eliminate these problems.

Summary of the Invention

According to a first aspect of the invention there is provided a device for parking an aircraft comprising anchoring means to anchor the aircraft down characterised in that the parking device further comprises a rotatable platform adapted to support an aircraft, the anchoring means being provided to anchor the aircraft to the platform, the rotatable platform with the aircraft attached thereto in use being adapted to rotate in strong winds such that the aircraft tends to face into the wind, the orientation of the platform changing as the wind direction changes such that the aircraft always tends to face windward. This has the advantage that it reduces the risk of any damage occurring to, for example, the rudder or elevator systems of the aircraft as a result of strong gusts of wind hitting the side or rear of the aircraft.

Preferably, the platform when supporting an aircraft is positively rotated to face into the wind by the action of the wind impinging on the aircraft, a change of wind direction causing a corresponding change in the orientation of the platform and thus the aircraft itself. This has the advantage that motorised means to rotate the platform do not need to be used.

Preferably, the platform has a plurality of stabilising wheels, the direction of

rotation of each respective one of which is substantially tangential to the radius of curvature swept out by the platform. The advantage of having stabilising wheels is that potential damage to the pivot means is reduced in strong winds as the wheels will tend to engage the ground and spread the load and also assist in the rotation of the platform if required.

Preferably, each respective one of the stabilising wheels is ground engaging. This will automatically spread the load acting on the pivot means, thereby prolonging its life.

Preferably the device comprises a ground engaging base, a pivot means and a platform, the pivot means comprising both stabilising wheels and a central pivot on the ground engaging base the separation of the base from the platform is adjustable such that the load on the platform when supporting an aircraft can be distributed between the pivot and the stabilising wheels. Making the separation of the base from the platform adjustable again has the advantage of spreading the load present on the platform and thus prolonging the lifetime and reducing the maintenance required on the pivot means. This also has the advantage of increasing the stability of the platform in, for example the loading or unloading of an aircraft onto and off the platform.

Preferably, the platform is provided with a locking means to prevent the platform from rotating when required. This has the advantage that the platform can be fixed in position and prevented from rotating during, for example, the loading or unloading of an aircraft onto or off the platform.

Preferably the device is provided with a winching means to enable a light aircraft to be winched onto the platform, thereby aiding the loading process.

Preferably, the platform comprises a framed structure. This is light-weight but robust and can therefore, undergo rotation relatively easily. Such a light¬ weight construction will also reduce shipping costs.

Preferably, the frame structure is substantially triangular in configuration and is provided with a ground engaging wheel at each apex, the direction of rotation of each respective wheel being substantial tangential to the radius of curvature swept out by the platform. This is advantageous as a triangular configuration is rigid, and also is the minimum shape required (thereby reducing the weight of the platform) to support an aircraft under carriage.

Preferably, the pivot means comprises a literal pivot point typically in the form of a roller bearing assembly. This is advantageous as such items are readily available, can support heavy loads and require minimum maintenance.

Preferably, the base comprises a concrete block and a pivot receiving member. This has the advantage that it is a cheap readily available form of large mass for securing a pivot receiving member.

Preferably, the combined mass of the concrete block and the remainder of the device once mounted to the concrete block is sufficient to prevent an aircraft when anchored to the platform and facing substantially into the wind from moving substantially vertically in strong winds, thus preventing potential damage to the aircraft and the device itself.

Preferably, the anchoring means comprises a net or mesh-like material that is so sized and shaped as to enshroud at least one wheel of an aircraft when supported on the platform. This readily adopts the shape of the wheel, once fastened and is thus a very tight fit to the wheel minimising aircraft movement when on the platform.

Preferably, the anchoring means is provided with quick release shackles, to enable the aircraft to be released from its anchoring device with the minimum of effort.

Preferably, the net or mesh-like material can be adjusted to fit any size wheel

of an aircraft. This will be able to anchor many types of light aircraft to a platform.

Preferably, the platform is provided with ramps to enable an aircraft to get on board the platform. This is advantageous if the platform is not substantially at ground level.

Preferably, the design of the pivot in conjunction with the platform when an aircraft is secured to the platform in use, will only be capable of rotation in winds of speeds of approximately 10 m.p.h or above, as this is the wind speed where potential damage and wear and tear of the control surfaces (e.g elevators, fins, rudder etc) especially to light aircraft begins to occur.

Preferably, the device is provided with an alignment means that is capable of extending beyond the platform to enable the pilot of an aircraft to first align the aircraft and then manoeuvre the aircraft into the correct position on the platform to enable the anchoring means to be attached to the aircraft. This will enable just the pilot whilst in the cockpit to manoeuvre the aircraft onto the platform.

Preferably, the platform is provided with a plurality of channels, each respective one of which is so sized and shaped as to accept a portion of each wheel of an aircraft. This serves the dual function of guiding the aircraft wheels into place and acting as a securing means as well if the anchoring means fail.

Preferably, the platform is positively oriented into winds via a motorised means. This could suit certain heavier platforms adapted to receive a range of aircraft types, some of which are less likely to rotate the platform if hit by wind alone.

The invention includes within its scope a device as substantially herein described with reference to and as illustrated in any appropriate selection or

combination of the accompanying diagrams, since this represents currently the best way known to the applicant of putting the invention into practice.

According to a second aspect of the invention there is provided a method of parking an aircraft comprising the steps of:

i) providing an aircraft parking device according to any preceding claim;

ii) actuating platform to ground engaging ramps from an aircraft parking device;

iii) manoeuvering a light aircraft up the ramps onto the platform of the parking device;

iv) securing the aircraft to the platform.

Brief Description of the Drawings

Figure 1 shows a perspective diagrammatic view of a light aircraft secured to a parking device embodying the invention.

Figure 2 shows a plan view of an alternative parking device embodying the invention.

Figure 3 shows a plan view of a more detailed axle assembly similar to that illustrated in Figure 2.

Figure 4 shows a side view of the axle assembly.

Figure 5 shows an end view of an axle assembly.

Figure 6 shows detailed plan and side views of the nose wheel channel that is

illustrated in Figure 2.

Figure 7 shows more detailed plan and side views of the rear wheel channels illustrated in Figure 2.

Figure 8 shows detailed plan and side views of the pivot receiving base plate again, as illustrated in Figure 2.

Figure 9 illustrates side and end views of a winching arm and locking device housing.

Figure 10 is a more detailed planned view illustrating the pivot gusset and support beam shown in Figure 2.

Figure 11 is a perspective view of one embodiment of the invention detailing the pivot assembly.

Figure 12 shows a section view of ramp.

Figure 13 shows both side and plan views of a ramp.

Figure 14 shows plan and section views of a mounting pin bearing housing.

Description of the Preferred Embodiments

The embodiments shown in the following figures represent currently the best way known to the applicant of putting the invention into practice. But it is not the only way in which this could be achieved. It is illustrated and will now be described by way of example only.

Throughout this specification, the use of the word integral is intended to cover not only something which is formed from the outset as one single-entity component but also anything which, whilst being assembled from a plurality

of initially disparately-produced integers, ends up as one overall and normally non-dismantable structure.

Throughout this specification, the use of the words anchoring means is intended to cover any method of securing an aircraft to a platform of the type described herein.

Throughout this specification the use of the word wheel is also intended to cover substantially spherical bodies, capable of rotating about an axis and also a load-bearing ball rotatable within a housing.

Figure 1 shows a light aircraft 10 secured to a turn-table platform 11. In use the aircraft is driven, hauled or otherwise man-handled up an apron 12 which bridges any difference in level between the surrounding meadow or hard standing and the top of the turn-table platform. Although this embodiment shows a turn-table which in effect has been placed atop the existing surface, it is equally possible that the top of the turn-table platform could be substantially flush with the existing surface. This can be achieved by excavating an area equivalent in size and shape to the turn-table and setting the turn-table into the recess thus created.

The apron need not extend around the entire perimeter of the platform but could alternatively take the form of a ramp wide enough to take the aircraft's undercarriage.

Once on the turn-table platform the aircraft is secured to prevent it rolling off. Especially designed anchoring points 13 are provided to facilitate quick and easy connection to a suitable part of the aircraft. In this example the connections are made under the wings, but the undercarriage, nose and tail are suitable locations. Quick-release type connectors can be used to simplify this operation.

Once secured onto the turn-table platform then any side wind will act on the

tail of the aircraft to rotate it so as to minimise this wind force, the forces being at a minimum when the plane faces directly into the wind.

The turn-table is adapted to be freely rotatable even when under the load of an aircraft. Turn-table assemblies are well known perse and a wide variety of known designs are appropriate and applicable to this use. For example, the turn-table could comprise a base and a platform, the platform being centrally pivoted on the base. The space between the two components is then filled with a fluid such as oil so that essentially the platform "floats" and rotates on a bed of oil producing only a small resistance to any turning force. Alternatively a system of low-friction ball or nylon bearings can be used around the perimeter of the platform to support it above the base and still allow it to rotate freely.

The design of the platform enables it to rotate freely through 360° yet still supports the weight of a light aircraft. The weight of the platform in this embodiment itself is more than sufficient to prevent lift-off in high wind conditions. The design incorporates a brake device to prevent rotational movement of the platform whilst an aircraft is manoeuvering on and off it. This brake mechanism can take a variety of forms, for example a locking bar which locks the platform to the base or a lever-activated brake such as is found on a wheeled vehicle hand brake.

The precise details needed to put the invention into practice will form an inevitable part of the common general knowledge of the intended skilled addressee of this specification.

Figure 2 shows a device for parking aircraft generally referenced as 20. The device comprises:

A substantially triangular platform 21;

Three wheel 22 and axle assemblies 23;

A nose wheel channel 24, port and starboard rear wheel channels 25;

A pivot receiving base plate 26; and

A pivot 27.

The platform 21 is of framed construction (for example, tubular or boxed steel) and consists of beams secured to each respective axle assembly 23 some of which are also secured to the pivot 27. In essence, the pivot provides a low friction, easily rotatable platform 21. Each axle assembly 23 is designed to accommodate three beams, two outer beams 28 and one inner beam 29.

Each outer beam 28 forms one side of the triangular structure of the frame 21 whilst each inner beam 29 is connected to the pivot 27 (which in this embodiment is found substantially at the centre of the triangular frame 21).

The frame 21 is also provided with two additional support beams 30 and 31. Both of these support beams provide support for the nose wheel channel 24 that is fitted to the frame 21 in use. One support beam 30 provides support for the nose wheel channel 24 along part of substantially the longitudinal axis of the channel 24 whilst the other provides support by bisecting another part of the longitudinal axis of the channel 24 substantially at right-angles.

In this embodiment, all of the beams that go to make up the frame are in substantially the same plane. The region where each respective inner 29 beam meets the pivot 27 is strengthened by a triangular gusset support plate

32 which also accommodates one of the support beam 30. This is shown in Figure 2 and more clearly in Figure 10.

The axle assemblies 23 that are secured to each respective apex of the frame

21 are shown in more detail in Figures 3 and 4. Each respective axle assembly comprises front 33 and rear 34 axle mounting plates and an axle 35.

In this context front means nearest to the wheel, when a wheel 22 is fitted to

-li¬ the axle 35. In this embodiment, the axle is of the KENDA "grasshopper" type.

Each respective front axle mounting plate 33 is secured to the ends of two outer 28 and one inner 29 beam of the frame 21. Each respective front axle mounting plate 33 is so shaped that the longitudinal axis of each respective beam (be it outer or inner), that it is attached to, meets the front axle mounting plate 33 at substantially right-angles.

As can be seen in both Figures 3 and 4, each respective axle 35 is connected to each respective axle assembly 23 and in this embodiment, each respective axle 35 is substantially coplanar with each other but they are not coplanar with the frame 21.

Each respective axle 35 passes through and is secured to an aperture in the front axle mounting plate 33 that is located vertically above the longitudinal axis of each respective inner 29 beam. This aspect of the assembly is clearly illustrated in Figure 5.

Each respective axle 35 once fitted to each respective front axle mounting plate 33 therefore sits vertically above each respective inner 29 beam and is parallel to it. Each respective rear axle mounting plate 34 is secured to one end of each respective axle 35 (as illustrated) and is also secured to each respective inner 29 beam adding support and rigidity to each respective axle

35.

A stabilising wheel 22 is fitted to each respective axle 35 and in this embodiment, each respective stabilising wheel 22 is ground engaging and comprises a tyre, inner tube and bearing. The direction of rotation of any wheel 22 fitted to such an axle 35 is going to be substantially tangential to the radius of curvature swept out by such a frame 21.

The frame 21 supports both a nose wheel channel 24 and port and starboard

rear wheel channels 25. Each respective channel, be it a nose wheel 24 or rear wheel 25 channel is so sized and shaped as to accept a portion of each respective wheel of an aircraft. As can be seen from Figure 2 the nose wheel channel 24 extends from substantially one axle assembly 23 (paralleling an inner 29 beam that is fitted to the axle assembly 23) and terminates by bisecting an outer 28 beam at substantially right-angles.

Both support beams 30 and 31 help to support the nose wheel channel 24 as previously indicated. It will be noted that in this particular embodiment the longitudinal axis of the nose wheel channel 24 does not substantially bisect the centre of the pivot 27. The channel 24 itself has a substantially flat bottom with tapering sides which help to both guide and maintain the nose wheel of a light aircraft within the confines of the channel 24. Where the channel 24 bisects the outer 28 beam at right-angled, two apertures 36 in the channel 24 can be seen. The portion of the channel 24 that accommodates the apertures 36 is angle downwards to support a ramp 50 these aspects of the channel 24 are more clearly defined in Figure 6. The ramp 50 enables an aircraft to get on board (or off) the frame 21.

Where the channel 24 meets the axle assembly 23 the channel 24 is provided with an angled front stop 37 that an aircraft nose wheel can abut.

The port and starboard wheel channels 25 are substantially parallel to the nose wheel channel 24 and are each secured to and supported by two outer 28 and one inner 29 beam (see Figure 2). They too, each have tapered sides and an angled front stop and also possess apertures 36 to accommodate a ramp. Again, the portion of the channel 25 that accommodates the apertures 36 is angled downwards.

Unique to the port and starboard channels 25, is an apertured protrusion 38 situated at the front of each channel, which is used to secure it to the frame 21. This is illustrated in Figure 7.

The frame 21 is mounted on a pivot 27 which in turn is mounted on a pivot receiving base plate 39 the latter is shown in detail in Figure 8. The pivot receiving base plate 38 comprises a substantially square plate that is apertured 40 at each corner and centrally apertured 41. Integral with but substantially perpendicular to the plate 39 is an elongate mounting pin 42, the longitudinal axis of which passes through substantially the centre of the aperture 41.

A concrete block (not illustrated) is adapted to receive the plate 39 which is secured to the concrete block through the use of securing pins that pass through the apertures 40. Together, the concrete block and the plate 39 form the based. A sufficiently sized concrete block needs to be used as part of the base in this particular embodiment to provide the device 20 with sufficient mass so that any tendency of an aircraft anchored to the platform to "lift" as a result of the wind is thwarted by the overall mass of the device (bearing in mind, the lightweight construction of the platform).

Once secured to the concrete block, the mounting pin 42 stands clear from the ground and is substantially vertical. The mounting pin 42 is adapted to receive a bearing and forms part of a roller bearing assembly.

The mounting pin bearing housing 43 illustrated in Figure 14 forms the second part of the roller bearing assembly and slides over the mounting pin

42, the two components housing a tapered roller bearing that forms the pivot means, (not illustrated).

The frame 21 at its centre is provided with a greased washer 44 which slides over the mounting pin 42. The gusset 32 of the frame 21, comes to rest on the mounting pin bearing housing 43 when the platform is in use. Frame 21 is then secured to the mounting pin 42 via an implement pin 45 which passes through the top portion of the mounting pin 42.

In this embodiment, the separation between the gusset 32 and the mounting

pin bearing housing 43 can be varied by introducing shims between the concrete block and the base plate 39 prior to securing the base plate 39 to the concrete block. The separation of the base from the platform is adjustable such that the load on the platform, when supporting an aircraft, can be distributed between the pivot and the stabilising wheels.

Illustrated in Figure 9 is a winching arm 46 that is part of the preferred embodiment but not illustrated in Figures 2 or 11. In place, the winching arm is secured in front of the wheel 22 that is, in turn, in front of the nose wheel channel 24. Integral with the winching arm 46 is a housing 47. This housing 47 accommodates a pointed rod (not illustrated) with a handle at one end to enable the rod to be withdrawn from the housing 47. The rod is used as a locking means to prevent the platform 21 from rotating when required (for example when loading or unloading an aircraft from the platform).

The locking means or rod in this embodiment, when used to prevent the platform 21 from rotating is pushed through an appropriately sized hole in the platform 21 (not illustrated) and is subsequently partially buried into the ground. The winching arm 46 is also provided with two loops 48 and 49.

These serve the purpose of attaching a winching means (in this case a block and tackle assembly) to the device 20. One end of the block and tackle assembly is secured to the loop 48, whilst the other is secured to the aircraft. The tackle in this particular embodiment provides the person pulling on it with a mechanical advantage of 8-1. Once both blocks have been fitted to the loop 48 and the aircraft is to be pulled onto the platform, the tackle passes through the loop 49 before being used in the loading process.

Before an aircraft can be loaded onto the platform, ramps 50 have to be fitted to the nose wheel 24 and rear wheel 25 channels. The ramps 50 are illustrated in Figures 12 and 13. As can be seen from these figures, each respective ramp 50 comprises a channel with tapered sides similar in design

and size to the tapered sides of the channels 24 and 25. As each respective ramp is not supported in some way by the underside of the frame 21, reinforcing bars 51 are secured to the underside of each respective ramp substantially along their longitudinal axis. Each respective ramp 50 is provided with two elongate plugs 52 that are substantially perpendicular to the ramp 50 and are situated at one end of the ramp 50.

The plugs, in use, mate with the apertures 36 present in the channels 24 and 25. Each respective ramp 50 is a true channel (unlike channels 24 and 25 which possess an angled front stop 37 at one end.

Once fitted, the ramps 50 in conjunction with the block and tackle will enable an aircraft to be hauled onto the platform.

Once loaded onto the platform 21, the aircraft in this preferred embodiment is anchored to the platform 21 through the use of net or mesh-like material (not illustrated) that is so sized and shaped as to enshroud the wheels 22 of the aircraft. The net or mesh-like material is adjustable to fit any sized wheel and is also provided with a quick release shackle (not illustrated) to allow rapid anchoring and de-anchoring of the aircraft.

In order to support such an aircraft on the platform 21 of the device 20, the device is generally formed from appropriately thick steel welded (or in the case of the channels 24 and 25 and the ramps 50 "bent") to form the appropriate structure.

Of course this embodiment although a preferred embodiment has been described by way of example only, a number of modifications can be made without departing from the scope of the invention.

For example, the platform need not necessarily be triangular in shape and the finished construction can be square, octagonal, oblong, circular etc. Furthermore, the nose wheel channel 24 illustrated in Figure 2 is shown to be

off centre with regards to the pivot 27. This is because some light aircraft possess nose wheels that are "off centre" from the underside of the fuselage. Alternative embodiments are intended to cover a nose wheel channel that can move (for example slide) across the frame to accommodate various types of light aircraft whose nose wheel can either be centrally located under the fuselage or non-centrally located under the fuselage.

The device could conceivably comprise a base and a platform centrally pivoted on the base, the "touching" surfaces of the base and platform being formed from a self lubricating material for example PTFE or the material used to manufacture artificial ice rinks.

The stabilising wheels in alternative embodiments need not necessarily be at the apex of the frame and could conceivably be interior to the frame.

In yet a further embodiment, the device can be so constructed that the wheels, instead of being directly ground engaging can rotate around a track or surface that is on or above the ground.

In yet a further alternative embodiment, the ramps could be hinged or otherwise fitted to the frame such that they can be raised from or lowered to the ground and locked in either position.

In yet a further alternative embodiment the ramps could be slidably fitted to the frame such that when not in use they simply slide up and into the nose and rear wheel channels.

A further embodiment could encompass a nose wheel channel with tapered sides that also has a tapered base. This form of nose wheel channel would be capable of extending beyond the platform to enable the pilot of a light aircraft to first align the nose wheel of the aircraft within the confines of the initially very wide nose wheel channel just visually and then he/she manoeuvers the aircraft closer to the platform, the tapered sides of the ever

narrowing nose wheel channel preventing the wheel from exiting the confines of the nose wheel channel and thus manoeuvre the aircraft onto the platform and into the narrow nose wheel channel that already exists on the platform without the assistance of any third party.

Another alternative embodiment that can be conceived of is one where the rotation of the platform is actuated by a motorised means, the motorised means being actuated by a wind velocity indicator fitted on or near to the device. The wind strength and direction signals are fed into a control unit which only sends instructions to the motor above a pre-determined wind speed. The motor is then activated to rotate the platform .such that the aircraft always faces windward, the motor/platform being calibrated such that the control means can monitor the orientation of the platform and thus the aircraft.

A yet still further alternative embodiment could encompass a flat sheet (either rigid or flexible) onto which the aircraft can be driven or pulled, the sheet being supported by a rigid base sheet and centrally pivoted. The lubrication between the two inner surfaces being provided by a suitable grease or some other form of lubricant which could include a self lubricating surface such as PTFE.

A further embodiment could encompass a flat rigid sheet onto which the aircraft can be driven or pulled, the sheet being supported by a bed of balls contained in a circular dish-like receptacle. The balls could be either lubricated metallic material or some form of self lubricating material (for example PTFE balls). The balls could even be made out of plastics material, the lubricant being water. In either event, the weight of the aircraft would be evenly distributed over a few hundred/thousand balls foπning one huge bearing. The anti-lift mechanism would be some form of shaft and pin linking the receptacle and top sheet, the receptacle being anchored to the ground.

A further embodiment similar to the arrangement just described is envisaged where the rigid sheet is supported by a fluid (either metallic or mineral) and relying on either surface tension to support the weight of the aircraft and sheet or a sealed system relying on hydraulic or pneumatic pressure to support the weight.

A final alternative embodiment is similar to the arrangement just described but the fluid used in this particular embodiment is a gas filled flexible container provided with some form of mechanical pump.