Abstract:
A trailer having a frame movable between a raised position, suitable for towing of the airplane on a roadway, and a lowered position, allowing the airplane wheels to be in contact with a common surface with the trailer wheels when the trailer is under the airplane. A hitch assembly, suitable for towing the trailer in a closed position with the frame in the raised position, is coupled to the front of the frame. The open position allows the airplane to be loaded/unloaded on land from the front of the frame when the frame is in the lowered position. The airplane may be loaded/unloaded from the rear of the frame when the airplane trailer is placed in water. Also, a method of loading the airplane onto the trailer from the rear in water and unloading the airplane from the front on land.

Description:
FIELD 
     The present invention relates generally to devices and methods of transporting an airplane from water to land and vice versa, and particularly from a towable trailer. 
     BACKGROUND 
     It is often desirable to transport water vehicles such as boats, personal watercraft and amphibious aircraft among different bodies of water by way of roads, or to withdraw such vehicles from the water, for instance, in anticipation of the water freezing. The transportation of water vehicles from land to water and vice versa is well known. Trailers which may be towed behind road vehicles to facilitate transportation with such water vehicles are also well known. 
     It is also known to transport other kinds of vehicles, such as land vehicles and aircraft, by road by loading them onto towable trailers. Small aircraft, for instance, may be towed on roads by placing them on trailers. Even land vehicles which may be perfectly capable of driving efficiently on roads may be loaded onto trailers and towed in order to, for instance, realize efficiencies in transportation or reduce vehicle wear and tear during transportation. 
     The ICON A5™ Amphibious Light Support Aircraft is designed and produced by ICON Aircraft. As an amphibious aircraft, the ICON A5 is configured to float on the water and to extend retractable wheels and roll on land. In order to protect the aircraft from weathering, it may be desirable to maintain the ICON A5 out of the water except during actual use, generally in an aircraft hanger, garage, or similar structure. 
     Traditional aircraft trailers for amphibious aircraft have been configured to be backed into water to allow the aircraft to float off and on the trailer. When the aircraft is to be taken off of the trailer on land to roll or rest on its own wheels, however, the aircraft may need to be physically lifted off of the trailer. The positioning of the wheels on the airframe of the ICON A5 may not be sufficiently wide to allow them to sit on the outside of the frame of the trailer, thereby constraining the wheels by the frame of the trailer itself. Moreover, the wheels on the ICON A5 may not deploy so low that they support the aircraft on the ground while the aircraft is positioned on the trailer even if the wheels were positioned outside of the frame of the trailer. Thus, because the aircraft wheels would not support the aircraft while the aircraft is on the trailer, and even if the wheels could support the aircraft, the wheels could not roll out of the frame, the aircraft may not be able to be placed on or removed from the trailer without additional equipment to, for instance, lift the aircraft off of the trailer. 
     SUMMARY 
     A trailer has been designed for use with water vehicles generally and amphibious aircraft in particular to facilitate the placement and removal of the aircraft from water, while also permitting the aircraft to roll off of and on to the trailer on its own wheels when on land. The trailer may be backed into the water down, for instance, a standard boat launch, and the amphibious aircraft floated over the rear or side of the trailer and secured to the trailer. With the aircraft secured, the trailer may be driven straight out of the water and to aircraft hanger, garage, or similar structure. Once at its destination the trailer may be unhitched from the towing vehicle, the aircraft wheels may be lowered and the trailer placed in a lowered and open configuration to allow the wheels of the amphibious aircraft to contact the ground and an open path for the amphibious aircraft to roll on its own wheels. If the trailer is positioned outside of the hanger or garage, the aircraft may roll directly into shelter. The aircraft may then be flown from a conventional airport using the aircraft&#39;s wheels. If the trailer was backed into the hanger or garage, the aircraft may be rolled off of the front of the trailer, facilitating maintenance or repositioning to an alternative structure, for instance. 
     In particular, a connecting mechanism between the trailer frame and the suspension allows for the frame to be raised and lowered, allowing for the aircraft wheels to come into contact with the ground and support the weight of the aircraft. Further, the lowered position of frame allows the airplane/trailer combination to enter or be stored in structures with a lower ceiling or door opening than would otherwise be the case. In addition, to permit the aircraft to then be rolled off of the trailer, a hitch assembly at the front of the trailer may be moved from a closed position, from which it may be utilized by another vehicle to tow the trailer, to an open position, in which the hitch is moved out of the way to give the wheels of the aircraft a clear path to allow the aircraft to roll over or out of the trailer. 
     As a result, no additional equipment may be needed to place an amphibious aircraft on the trailer or take the amphibious aircraft off the trailer while on land. Moreover, additional effort or strain may be minimized in such an operation, as manhandling of the aircraft may be minimized. These advantages may be realized while maintaining essential functionalities of the trailer itself, in particular providing the ability to hitch the trailer to a towing vehicle, drive the trailer to water, place the trailer in water and allow the amphibious aircraft to float off of the trailer, particularly off of the back. 
     In an embodiment, the present invention provides a trailer for an airplane having a flotation hull and retractable airplane wheels. Trailer wheels are mounted with respect to a trailer suspension. A connecting mechanism operatively couples a frame having a front and a rear to the trailer suspension. The connecting mechanism allows the frame to be moved between a raised position of the frame relative to the trailer wheels and a lowered position of the frame relative to the trailer wheels. The raised position is suitable for towing the airplane on the airplane trailer on a roadway. The lowered position is suitable for allowing the airplane wheels to be in contact with a common surface with the trailer wheels when the trailer is under the airplane. A hitch assembly having a closed position and an open position is coupled to the front of the frame. The closed position is suitable for towing the trailer with the frame in the raised position. The open position allowing the airplane to be loaded/unloaded on land from the front of the frame when the frame is in the lowered position. The trailer being constructed such that the airplane may be loaded/unloaded from the rear of the frame when the airplane trailer is placed in water. 
     In an embodiment, the hitch assembly is movable to the open position. 
     In an embodiment, the hitch assembly is movable to a first side of the frame to the open position. 
     In an embodiment, the hitch assembly is pivotally coupled to the frame. 
     In an embodiment, the hitch assembly has a first arm pivotally coupled to the frame and a second arm pivotally coupled to the frame and detachably attached to the first arm, wherein the first arm and the second arm are movable to the open position when the first arm is detached from the second arm. 
     In an embodiment, the frame has a second side, and wherein the first arm is movable to the first side to the open position and the second arm is movable to the second side to the open position. 
     In an embodiment, the hitch assembly comprises an arm pivotally coupled to the frame movable to a side of the frame to the open position. 
     In an embodiment, the connecting mechanism has a piston pivotally coupled to the frame and providing a piston force, a suspension lever operatively coupled to the trailer suspension and a transfer lever pivotally operatively coupled to the piston and pivotally coupled to the suspension lever. The frame moves between the raised position and the lowered position due to an action of the piston force on the transfer lever. 
     In an embodiment, the piston is a hydraulic piston. 
     In an embodiment, the frame is at least eight (8) inches higher above the trailer wheels in the raised position compared with the lowered position. 
     In an embodiment, the connecting mechanism operates independently of the trailer suspension. 
     In an embodiment, a raised performance of the trailer suspension with the frame in the raised position approximately equals a lowered performance of the trailer suspension with the frame in the lowered position. 
     In an embodiment, the trailer suspension may consist of one or more torsion axles. 
     In an embodiment, the airplane has retractable wheels and the airplane wheels are in contact with a common surface with the trailer wheels when the frame is in the lowered position and the retractable wheels are in an extended position. 
     In an embodiment, the raised position is suitable for towing the airplane on the airplane trailer on a roadway when the retractable wheels of the airplane are in a retracted position. 
     In an embodiment, the retractable wheels of the airplane interfere with loading/unloading of the airplane from the front of the trailer when the retractable wheels are in the extended position and the hitch assembly is in the closed position. 
     In an embodiment, the retractable wheels of the airplane clear the hitch assembly during loading/unloading of the airplane from the front of the trailer when the retractable wheel are in the extended position and the hitch assembly is in the open position. 
     In an embodiment, the present invention provides a method of loading/unloading an airplane having retractable airplane wheels and a flotation hull on to/off of a trailer. The trailer has a frame having a front and a rear and a hitch assembly operatively coupled to the front of the frame, the hitch assembly having an open position and a closed position. The frame is movable between a raised position and a lowered position. If loading, the frame is moved to the lowered position. The hitch assembly is moved to an open position. Then, the airplane is rolled on the retractable airplane wheels over the trailer from the front of the frame. The hitch assembly is moved to a closed position. The frame is moved into the raised position. Then, the retractable wheels of the airplane are retracted. If unloading, all of the preceding steps are performed in the opposite order with extension of the retractable aircraft wheels instead retracting the aircraft wheels. 
     In an embodiment, the present invention provides a method for loading from water and unloading from land an airplane having retractable airplane wheels and a flotation hull using a trailer having a frame having a front and a rear and a hitch assembly operatively coupled to the frame, the hitch assembly having an open position and a closed position. The frame is movable between a raised position and a lowered position. The trailer is placed into water. The airplane with the retractable airplane wheels in a retracted position is floated over the frame from the rear of the frame. Then, the trailer is pulled out of the water. If the frame is in the lowered position, the frame is moved to the raised position. The airplane is transported on the trailer. The retractable wheels are extended to an extended position. The frame is moved to the lowered position. The hitch assembly is moved to the open position. Then, the airplane is rolled off of the trailer on the retractable airplane wheels over or out of the front of the frame. 
    
    
     
       DRAWINGS 
         FIG. 1  shows a trailer for a water vehicle; 
         FIG. 2  shows the trailer of  FIG. 1  in a lowered position and with a hitch assembly in an open position; 
         FIG. 3  shows the trailer of  FIG. 1  with an amphibious aircraft on the trailer; 
         FIG. 4  shows the trailer as in  FIG. 2  with an amphibious aircraft on its aircraft wheels over the trailer in a lowered position; 
         FIG. 5  is a top view of trailer suspension and connecting mechanism; 
         FIGS. 6   a - 6   c  are side views of a trailer suspension and connecting mechanism illustrating a transition from a raised position to a lowered position; 
         FIG. 7  is a perspective view of a trailer suspension and connecting mechanism; 
         FIG. 8  is a top view of a hitch assembly; 
         FIG. 9  is a flowchart for using a trailer to transport an amphibious aircraft from land to water; and 
         FIG. 10  is a flowchart for using a trailer to transport an amphibious aircraft from water to land. 
     
    
    
     DESCRIPTION 
     It is often advantageous to provide a trailer for moving water vehicles such as amphibious aircraft into and out of the water. While such water vehicles may be able to be maintained in the same body of water for extended periods of time, it may be inconvenient or potentially damaging to leave them in the same body of water indefinitely. A trailer on which the water vehicle may be secured while in the water and moved onto land allows for the water vehicle to be moved on land. 
     However, because of the limitations of conventional trailers, amphibious vehicles such as amphibious aircraft, which have an ability to move about on water and land, may not be efficiently utilized due to a difficulty or outright inability to remove the amphibious vehicle from the trailer. A trailer has been developed to allow for what may be an easier procedure to allow for the removal and replacement of an amphibious aircraft on land. 
     An embodiment of a trailer is shown in  FIG. 1 . Trailer  10  may be built primarily around frame  12 . Support structure  13  combines with support pads  11  to support an amphibious aircraft. Support structure  13  is removable from frame  12  to allow for removal of the amphibious aircraft from trailer  10 . Support structure  13  and support pads  11  may be repositioned or reconfigured to support particular kinds of amphibious aircraft or other types of water vehicles. Trailer wheels  14  may allow for trailer to move easily on land, particularly on conventional roads. Wheels  14  may also be configured to support trailer  10  on boat launches and other similar structures designed to facilitate the transition of water vehicles from trailers to water or from water to trailer. Wheels  14  are coupled to trailer suspension  16  by way of spindles  15 . In various embodiments, trailer suspension  16  may be one or more torsion axles. Alternative embodiments may utilize any suitable suspension article known in the art. 
     Trailer suspension  16  is coupled to frame  12  by way of connecting mechanism  18 , detailed in  FIGS. 5-7 . Connecting mechanism  18  may be built primarily around a device configured to raise and lower frame  12  relative to a surface contacted by wheels  14 . In the illustrated embodiment, connecting mechanism  18  is built around a piston  19  coupled to one or more levers  21 . Alternative embodiments of trailer suspension  16  are envisioned. 
     Trailer hitch  20  is illustrated in a closed position, and is detailed in  FIG. 8 . In the illustrated embodiment, trailer hitch  20  is Y-shaped. Alternative embodiments, such as T-shapes and bars that simply span the gap created in frame  12 , are also envisioned. As illustrated, hitch arms  22 ,  24  are pivotally attached to frame  12  at joints  26 ,  28 . Hitch arms  22 ,  24  are separably connected at junction  30  and allowed to swing open by way of joints  26 ,  28 . In alternative embodiments, joint  26  may be a separable junction and junction  30  may be inseparable, configuring hitch  20  to swing to an open position only on joint  28 . Alternatively, joint  26  may be a separable junction and junction  30  may be a pivot joint, allowing an open position for hitch  20  to involve folding arm  24  against frame  12  and arm  22  against arm  24  in the manner of an articulated member. Support wheels  27 ,  29  may be deployed to support the front of trailer  10 . 
       FIG. 2  shows trailer  10  in a configuration to allow for an aircraft to roll on and off through open trailer hitch  20  of trailer  10  supported by the aircraft&#39;s wheels. Connecting mechanism  18  is in a lowered position, raising the position of wheels  14  with respect to frame  12  and lowering frame  12  relative to a surface on which wheels rest. In an embodiment, this lowering may allow wheels of a water vehicle, in particular an amphibious aircraft, to come into contact with the ground. Impediments to independent movement of the amphibious aircraft may then be removed. As illustrated, support structure  13  has been removed. In addition, trailer hitch  20  has been moved to an open configuration by releasing junction  30  and pivoting arms  22 ,  24  about pivots  26 ,  28 . Combined, these adjustments to trailer  10  may allow a water vehicle positioned on trailer  10  with deployed wheels in contact with the ground forward of trailer suspension  16  to roll through of open front  32  of trailer  10 . 
       FIG. 3  illustrates amphibious aircraft  40 , as illustrated an ICON A5 amphibious aircraft, positioned on trailer  10 . Trailer  10  is in the configuration consistent with the configuration of  FIG. 1 . Both trailer  10  and amphibious aircraft  40  are configured for travel on land or onto a structure for positioning amphibious aircraft  40  in water. Amphibious aircraft  40  does not have deployed wheels, and wings  42  are folded back for transportation. In such a configuration, if trailer  10  is hitched to a towing vehicle, trailer  10  and amphibious aircraft  40  may be towed on a road or other suitable surface efficiently and safely. 
       FIG. 4  illustrates amphibious aircraft  40  positioned over trailer  10 , with trailer  10  and amphibious aircraft  40  both configured to allow amphibious aircraft  40  to roll through of front  32  of trailer  10 . Trailer  10  is in a configuration consistent with that illustrated in  FIG. 2 . Wheels  44  of amphibious aircraft  40  have been deployed and are in contact with a surface due to moving frame  12  of trailer  10  to a lowered position. The removal of support structure  13  and the opening of trailer hitch  20  allow for a clear path for amphibious aircraft  40  to roll forward without obstruction. 
       FIG. 5  shows a close-up, top view of trailer suspension  16  and connecting mechanism  18 . In the illustrated embodiment, connecting mechanism is comprised of a pair of pistons  19 . In alternative embodiments, only one piston  19  is utilized. In alternative embodiments, more than two pistons  19  are utilized. In the illustrated embodiment, pistons  19  are coupled to frame  12  by way of pivots  50 . In alternative embodiments, pistons  19  do not pivot with respect to frame  12 . In the illustrated perspective, a portion of connecting mechanism  18  is obscured. However, pistons  19  are coupled to those obscured portions by way of pivots  52 . 
     Likewise obscured from the illustrated perspective is the coupling of connecting mechanism  18  to trailer suspension  16 . In an embodiment, torsion axle  60  is coupled to torsion arms  62  after passing underneath frame  12 . Torsion arms are rotationally coupled to wheel hub spindles  15  (obscured), onto which wheels  14  are rotationally coupled. 
       FIGS. 6   a - 6   c  illustrate a transition from a raised to a lowered position of trailer suspension  16  and connecting mechanism  18  from a side view from the A-axis shown in  FIG. 5 . As illustrated in  FIG. 6   a,  wheels  14 , trailer suspension  16  and connecting mechanism  18  are in their lowered position while frame  12  is raised relative to spindle  15 . In  FIG. 6   b,  the raised position of frame  12  corresponds to the solid-line representation, while the lowered position of frame  12  corresponds to the dashed-line representation.  FIG. 6   c  illustrates the lowered position of frame  12 . 
     Piston  19  is coupled to lever  21  by way of pivot  52 . Lever  21  is coupled to torsion axle  60 . Torsion axle  60  is coupled to lever  64 , which is coupled to frame  12  by way of pivot  66  which is fixed to frame  12 . As piston  19  retracts, as illustrated in  FIG. 6   b,  lever  21  imparts rotational force on torsion axle  60  which pivots about pivot  66  by way of lever  64 . The rotation of torsion axle  60  imparts rotational force on torsion arm  62 , which causes wheel hub spindle  15  and wheel  14  to rise relative to frame  12 . As illustrated in  FIG. 6   c,  with piston  19  retracted either completely or nearly completely, wheel hub spindle  15  is approximately equal in height with frame  12 , compared with being distinctly lower than frame  12  in  FIG. 6   a.  Different heights of wheel hub spindle  15  relative to frame  12  are envisioned in alternative embodiments. 
     In various embodiments, a difference in length between lever  21  and torsion arm  62  imparts a variable difference in the degree to which wheel hub spindle  15  and wheel  14  rise or fall based on the action of piston  19 . Where torsion arm  62  is relatively longer than illustrated or lever  21  is relatively shorter than illustrated, wheel  14  may rise or fall by greater amounts than illustrated without changing characteristics of piston  19 . The corollary applies, wherein a shorter torsion arm  62  and a longer lever  21  may result in wheel  14  rising and falling by lesser amounts than illustrated. However, varying the length of either lever  21  or torsion arm  62  may change the amount of force required from piston  19  in order to raise or lower wheel  14 . As such, in various embodiments, piston  19  and lengths of lever  21  and torsion arm  62  may be selected to improve an efficiency between performance of piston  19  and movement of wheel  14 . In an embodiment, piston  19  has five and one-half inches (5½″) of travel, lever  21  is four and three-fourths inches (4¾″) long and torsion arm  62  is six inches (6″) long. 
       FIG. 7  is a perspective image of trailer suspension  16  and connecting mechanism  18 . Piston  19  is partially visible and is connected to lever  21  by way of pivot  52 . Lever  21  is connected to torsion axle  60 , which is coupled to lever  64 . Lever  64  is coupled to pivot  66  which is fixed to frame  12 . Torsion arm  62 , partially obscured, is connected to torsion axle  60 , and wheel hub spindle  15  is connected to torsion arm  62 . Wheel  14 , not shown, spins about wheel hub spindle  15 . 
       FIG. 8  shows trailer hitch  20 . The solid line representation shows trailer hitch  20  in its closed position. The dashed line representation shows trailer hitch  20  in its open configuration. 
     As described above, arms  22 ,  24  are pivotally attached to frame  12  by pivots  26 ,  28  held by pins  23 ,  25 . Arms  22 ,  24  may be secured to one another by removable pins  70 . With arms  22 ,  24  joined together and pins  23 ,  25 ,  70  inserted, hitch  20  may be resilient enough to allow a vehicle to be joined with trailer hitch  20  at ball hitch  72 , which may allow the vehicle to tow trailer  10 . 
     With removable pins  23 ,  25  removed and pins  70  removed, arms  22 ,  24  may swing on pivots  26 ,  28  to the open position. Arms  22 ,  24  may be supported in the open position by support wheels  27 ,  29 . In various embodiments, arms  22 ,  24  swing open by varying amounts. In an embodiment, arms  22 ,  24  swing open just sufficiently far enough to create a gap sufficient to allow the passage of amphibious aircraft  40 . In alternative embodiments, arms  22 ,  24  may swing open wider, in various embodiments until arms  22 ,  24  are flush or approximately flush with frame  12 . 
       FIG. 9  is a flowchart showing the process by which trailer  10  may be utilized to load and transport amphibious aircraft  40  from land into water. If hitch assembly  20  is not already in an open position, hitch assembly  20  is moved ( 900 ) into its open position by removing the removable pins  23 ,  25  and pins  70  and swinging arms  22 ,  24  about pivots  26 ,  28  to an open position. With wheels  44  deployed, amphibious aircraft  40  may then be rolled ( 902 ) through open front  32  of trailer  10  by rolling amphibious aircraft  40  over trailer  10 . Amphibious aircraft  40  may optionally be secured ( 904 ) to trailer  10 . Hitch assembly  20  may be moved ( 906 ) into its closed position by closing arms  22 ,  24  and inserting removable pins  23 ,  25  and pins  70 . Optionally, support structure  13  may be installed ( 907 ). Then frame  12  is placed ( 908 ) into its raised position by operating piston  19 . 
     After amphibious aircraft  40  is rolled over frame  12  in step ( 902 ) and, optionally, support structure  13  put back in place ( 907 ), wheels  44  are retracted ( 910 ). Trailer  10  may then be transported ( 912 ) into water and amphibious aircraft  40  may be floated ( 914 ) off of trailer  10 . In various embodiments, amphibious aircraft may be floated off of trailer  10  by floating over the rear of trailer  10 . 
       FIG. 10  is a flowchart showing the process by which amphibious aircraft  40  may be removed from water using trailer  10 . If hitch assembly  20  is not already in a closed position and trailer  10  not already in a raised position, hitch assembly  20  is placed ( 1000 ) in a closed position and piston  19  manipulated to raise frame  12 . Frame  12  is then placed ( 1002 ) into water, by rolling it into water or by some other method. Amphibious aircraft  40  may then be floated ( 1004 ) over frame  12  and, optionally, secured ( 1006 ) to frame  12 . 
     Trailer  10  may then be transported ( 1008 ) out of water. Once out of water and placed near a spot in which amphibious aircraft is to be moved, aircraft retractable wheels  44  may be lowered ( 1010 ) and frame  12  is moved ( 1012 ) to a lowered position. Hitch assembly is moved ( 1016 ) into its open position and, optionally, support structure  13  ( 1014 ) is removed. After this, amphibious aircraft  40  may be rolled ( 1016 ) on its wheels  44  off of trailer  10  over front  32  of frame  12 . 
     Thus, embodiments of the devices, system and methods of the airplane trailer are disclosed. One skilled in the art will appreciate that the present invention can be practiced with embodiments other than those disclosed. The disclosed embodiments are presented for purposes of illustration and not limitation, and the present invention is limited only by the claims that follow.