CA2945967A1

CA2945967A1 - Amphibious stol aircraft

Info

Publication number: CA2945967A1
Application number: CA2945967A
Authority: CA
Inventors: Claire Miller
Original assignee: Individual
Current assignee: Individual
Priority date: 2016-10-19
Filing date: 2016-10-19
Publication date: 2018-04-19

Abstract

The amphibious STOL aircraft has wings comprising outer and inner segments.
The inner segments of the wings are attached to the fuselage of the aircraft while the outer wing segments are detachable and attachable to the inner segments. The outer segments can also be folded relative to the inner segments from an inoperative position adjacent to the side walls of the fuselage to an operative position in which the outer wing segments extend outward from the inner segments and the two segments combine to support the aircraft when airborne.

Description

This invention relates to amphibious aircraft and more particularly to an amphibious STOL aircraft.
Many fixed-wing STOL aircraft are designed for use in sparsely populated areas where loads are usually limited and where runways are short or non-existent. Such aircraft are in use in dense bush and in wilderness and tundra where conditions are harsh and distances between settlements is vast.
The aircraft of my invention is an amphibious STOL aircraft and has a number of features which make it suitable to conditions which are generally unfavourable to flight. The unfavourable conditions may be the absence of runways, runways that are disused and not in a good state of repair, runways covered in ice or hard-packed snow in winter, and in locations where mainten-ance and repairs to aircraft are not available.
The features which my aircraft has which enhance its usefulness in such conditions are many. Where my aircraft is taking off from water, air under pressure can be directed to the water o create turbulence which assists in reducing the drag of the water so that the aircraft may become airborne more rapidly and hence require a shorter body of water to do so. Where maintenance or repairs may be necessary, the wings of my aircraft can be folded in or be entirely removed so that the aircraft can be towed on its main wheels to where those tasks can be carried out.
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These are some but no means all of the features which enhance the usefulness of the aircraft in difficult conditions. Briefly the aircraft of my invention is amphibious and has a fuselage and wings. The wings have outer and inner segments. The inner segments of the wings are attached to the fuselage while the outer wing segments can be both detached and attached to the inner segments. The outer segments can also be folded relative to the inner segments from an inoperative position adjacent to the side walls of the fuselage. In this position the aircraft can be towed or stored. From the inoperative position the aircraft can be unfolded to an operative position in which the outer wing segments extend outward from the inner segments and the two segments combine to support the aircraft when airborne.
The aircraft is described in detail with reference to the accompanying drawings in which:
Figure 1 is a perspective view of the aircraft of the invention;
Figure 2A is a perspective viw of the underside of the aircraft;
Figure 2B is a section on line 2-2- of Figure 2;
Figure 3 is an elevation of the aircraft;
Figure 4A-4D are elevations of the aircraft in the process of taking off;
Figure 5 is an elevation, partly cut away, of the front of the aircraft;
Figure 6 is another elevation of the front of the aircraft, partly cut away to show the gear train of the retractable landing gear of the aircraft;
Figure 7 is an exploded perspective view of the retractable nose wheel of the aircraft;

2.1 AP

Figure 8 is an elevation of the nose wheel in a retracted position;
Figure 9 is an elevation of the nose wheel in an operative position;
Figure 10 is an exploded perspective view of the retractable rudder of the aircraft;
Figure 11 is an elevation of the retractable rudder in an inoperative position;
Figure 12 is a plan view of the aircraft;
Figure 13 is a plan view of one half of the aircraft;
Figure 14 is an elevation of the fastening mechanism for interconnecting the two segments of one wing, in an inoperative position;
Figure 15 is a plan view of the fastening mechanism in an inoperative position;
Figure 16 is a perspective view of the fastening mechanism;
Figure 17 is an elevation of the fastening mechanism in an operative position;
Figure 18 is a plan view of the fastening mechanism in an operative position;
Figure 18 is a plan view of the aircraft in which the outer segments of the wings are separated from the inner segments;
Figure 20 is a perspective view of the aircraft in which the outer segment of the wings are folded against the fuselage;
Figure 21A is a paetial perspective view of the outer and inner wing segments;
Figure 21B is a perspective view of the two segments of the wing separated from one another;
---Figure 22 is an elevation of a side wall of the inner wing segment;
Figure 23 is an elevation of the two wing segments in the process of being separated from one another; and Figure 24 is an elevation, in enlargted scale, of the cross-section of a passageway in the inner wing segment.
Like reference characters refer to like parts throughout the following description of the aircraft of the invention.
With reference to Figures 1 and 2A and 2B, the aircraft of the invention comprises a fuselage 10, a propeller 12, wings 14 having ailerons and flaps 14a, 14b and a tail 16 having a rudder 18. The aircraft has a longitudinally extending axis 20 which lies on a plane of symmetry 22 of the aircraft. The plane divides the left and right segments 22a, 22b, respectively.
With reference to Figure 2B, the bottom wall, generally 24 of the fuselage comprises a so-called "tunnel" 24 disposed symmetrically about plane 22 and defined by a V-shaped central wall 26a and a pair of second walls 26b which extend vertically downwardly at opposite ends of the central wall.
The lower end of each second wall terminates at a third wall 26c which extends horizon-tally outward and normal to the plane of symmetry. The third walls are the lowest area of the bottom wall and function as skis on which the aircraft slides when it is taking off or landing on ice or hard-packed snow.
_ 4_,.

The outward edge of each third wall terminates at a fourth wall 26d which extends up-wardly and outwardly of the plane of symmetry and terminates at a side wall 10a of the fuselage.
Each third wall functions to force snow which is in drifts or is loose on the path of the aircraft outward and away from the aircraft as it taxis forward in preparation for take-off or during landing.
With reference to Figure 3, the aircraft is provided with a retractable rudder 28 (described below) beneath the aircraft and a tube 30 which extends from an inlet 30a forward of the pylon 32 for supporting the propeller engine 34. The tube is also shown in Figure 6.
The tube extends to an outlet 30b at the forward end of tunnel 24b in the bottom of the fuselage. The tube functions to provide a passage for air under pressure for discharging into the water beneath the fuselage. The air creates bubbles and turbulence in the water and lessens the suction of the water on the bottom wall of the aircraft as the aircraft is preparing for take-off With reference to Figure 4A, the aircraft is lying horizontally in the water before the pro-peller begins to rotate. In Figure 4B, propeller 12 begins to draw air to the rear and the ailerons direct the air to beneath the wings and cause prow 10b of the aircraft to tilt upward. In Figure 4C, the pressure of the air beneath the wings as well as the turbulence in the water beneath the aircraft causes the craft ro rise to the surface of the water and in Figure 4D, the aircraft is airborne.

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In Figures 5 and 6, the retractable main landing gear is illustrated. A pair of main wheels 40, 42 are each disposed adjacent to a separate side wall 10a. A conventional brake (not illus-trated) is provided to reduce the forward movement and to steer the aircraft.
The apparatus for causing the wheels to extend and retract comprises a pair of gear trains consisting of a number of bevel gears, gear wheels, worm gears and rack as follows: (i) a central bevel gear 44 activated by a motor (not illustrated) is the prime mover of the gear train. The central gear rotates selectively in clockwise and counterclockwise directions depending on whether the wheels are rising from the position outside the wheel housing 46 illustrated in Figure following take-off or are descending from the position within the wheel housing illustrated in Figure 6 prior to landing.
To avoid confusion, the gears of only one gear train are identified. The gears in the other grain are mirror images of the latter gear train A pair of (ii) second bevel gears 47a, b mesh with central gear 44. The second gears are on opposite sides of the central gear and rotate in opposite directions. A pair of (iii) third bevel gears 48a, b are connected to the second gears and rotate with them. A pair of (iv) fourth bevel gears 49a,b mesh with the third bevel gears and are con-nected by means of rods 50a,5 to (v) worm gears 53a,b, generally referred to as "worms".
The worms mesh with (vi) inner gear wheels 52a,b and the latter gears rotate with (vii) outer worm gears 53a,b which in turn mesh with the teeth of (viii) rack 54a,b.
The latter racks rise and descend at the same time to raise and lower connecting rods 56a,b which are connected to wheels 40, 42 respectively.
The wheels advance from wheel wells 46 and retract to them depending on whether racks 54a, b are rising or falling. Doors 58 on each wheel well are opened and closed by the wheels as they ascend and descend. As illustrated in Figure 5, as the wheels descend they push against each door and causes the doors to swing outwatd and the doors open. In Figure 6 as each wheel ascends, it pushes against the doors and causes them to close.
With reference to Figures 7 and 3. a retractable nose gear, generally 60, has a front wheel 62 and a wheel well 64 for accommodating the wheel. The wheel is rotatable about an axle 66 which is attached to the lower vertical tube 68. A lower plate 70 is attached to the upper end of the tube and a groove is formed in plate 70a.
An upper tube 74 has an upper plate 74 adjacent to its lower end. The lower end fits into the bore of the lower tube 68 and its upper plate rests on the lower plate 70.
A bolt 76 threadably fits through an opening in the upper plate and through groove 70a in the lower plate. Tightening of nut 80 to the bolt interconnects the two plates. A spring-loaded plunger, generally 82, consisting of a washer 82a, coil spring 86, and tubes 82b, 82d inner tubes, outer and inner tubes is attached to the upper tube by means of bolt 84. The plunger fits in an opening in the upper plate and bears against a depression 86 in the lower plate to prevent the wheel from swivelling from a position in which its axle 66 is normal to the longitudinal axis of the aircraft.

A collar 90 encircles the upper tube and a pair of diametrically opposed pivot pins 99 are attached to the collar and to a wall of wheel well 64 so that upper and lower tubes as well as the wheel are pivotal from the retracted position as illustrated in Figure 8 to an operative position illustrated in Figure 9. A door for the wheel well consisting of forward and rear segments 96a, b respectively are provided for opening and closing of the wheel well.
The upper end of the upper tube 72 is attached to a handle 100 which extends into the cockpit of the aircraft for manual control of the front wheel 62 from within the cockpit.
With reference to Figures 10, 11 and also Figure 3, the retractable rudder 28 is attached to a vertical rod 110. A ring 112 at the top of the rod is attached to a cable 114 which extends to the cockpit where it can pulled manually to lift the rod and rudder into rudder well 116. The ring is attached to a swivel 113 so that rotation of the rod does not produce a like rotation of the ring.
When the cable is released, gravity will cause the rudder to descend into the water beneath the aircraft as depicted in Figure 3.
As indicated below, rod 110 causes the rudder to turn but does not produce movement of the cable.
Rod 110 is free to slide vertically in an opening 120a in a retainer 120. The retainer is secured to a wall of the fuselage by a bracket 122 and its elevation remains fixed but it is free to pivot in relation to the bracket. Attached to the rod in proximity to its upper end is a hexagonal nut 122. The nut fits into an opening 120a which has hexagonal walls whch conform to the shape of the walls of opening 120a when the rudder is in the water and the rod is at its lowest extent.
The retainer being secured to the retainer when at its lowest extent pivots attached as the retainer pivots, to rod 120 pivots as the rod rotates. A pair of cables 130a,b causes the retainer to pivot. The cables extend to the cockpit where they are controlled by pulling of one or the other cable. For example, when cable 130a is pulled to the left in the direction of the arrow adjacent to it, retainer 120 pivots counterclockwise. Simultaneously cable 130b moves to the right. Nut 122 being in the recess in the retainer causes rod 120 also to pivot counterclockwise as does rudder 28.
Cables 130a,b extend to the tail rudder 18 (Figure 1) and control its orientation in the usual manner so that both rudders move at the same time and are always at the same angle.
With reference to Figures 12 and 13, the main spar 132 of the aircraft extends the length of both wings as is conventional and the wings of the aircraft contain the usual cables which control the flaps and ailerons in the conventional manner.
The fastening mechanism for securing the two wing segments together is illustrated in Figures 14 - 16. As previously indicated, each wing, generally 150 is composed of two segments, an inner segment 152 which is attached to the fuselage of the aircraft and an outer segment 154 which is designed to be attached to the inner wing segment and detached from it. To this end, the outer wing segment is provided with a tongue 156 which projects inward from an inner wall 154a of the outer wing segment.

As illustrated in Figure 6, the inner wing segment is provided with a panel 160 having a hollow interior 160a. The tongue has side edges 158 which conform to the side edges 160b of the hollow interior in order to minimize the sideways movement of the outer wing segment relative to the inner wing segment when the two wing segments are interconnected.
With reference to Figures 14 - 16, a lever 170 pivots about a fulcrum 172 on the exterior of panel 160. The lower end of the lever is pivotally connected to an arm 174 which extends toward the tongue and terminates at an inwardly extending tab or catch 176.
The direction of movement of the arm is guided by a pair of spaced apart and parallel wedges 178 and a bar 180 which limits the movement of the arm away from the panel.
The upper end of the lever functions as a handle and is located within the fuselage of the aircraft where it can be manipulated by occupants of the aircraft. The direction of movement of the handle is guided by a V-shaped bar 172 which in turn is guided by pins 173 in the outer wall of panel 160.
A short rod 190 is attached to the underside of arm 174 and slides along the upper walls of the two wedges 178 as the lever causes the arm to advance from an inner position illustrated in Figure 14 to an outer position illustrated in Figures 16 and 17. As the arm advances, the wedges cause tab 176 to swing from a so-called engaged position as illustrated in Figure 15 to a dis-engaged position illustrated in Figure 18. The tab is engaged when it extends through an opening 200 in panel 160 and into opening 202in tongue 156. The tab is disengaged when it is outside the ¨1 0--two openings. When engaged, the tab functions to fasten the outer wing segment to the inner wing segment and to prevent the two segments from separating. When the tab is disengaged, the two wing segments can be separated from one another.
With reference to Figure 18, when the tab is engaged, the inner wall 204 of the outer wing segment abuts the outer wall 206 of the inner wing segment. When the two wing segments no longer abut one another, the outer wing segment may be folded against the outer wall of the fuselage as is explained below.
The components required for folding are illustrated in Figures 21A,B, - 23.
With reference first to Figure 21A, an elongated connecting rod, generally 250, has a cylindrical cross-section except for a protrusion 252 which is attached to the inner end of the rod and which extends rad-ially outward from the rod.
The connecting rod is composed of two portions, an inner portion 250a and an outer portion 250b interconnected by a pivotal connection, generally 254, which pivots about a pin 256.The pin extends horizontally and parallel to the longitudinal axis of the aircraft.
The outer portion of the connecting rod is secured immovably in a hollow in the outer wing segment 260 while the inner portion extends through an entrance 262 in the outwardly facing wall 264a of the inner wing segment 264 and into a hollow passageway 266. The passageway terminates at the oppositely facing wall 264b of the inner wing segment.
¨it--With reference to Figures 21B and 24, the passageway has a cross-section which is com-posed of two parts, one numbered 270a which is cylindrical in shape and the other numbered 272 which is in the shape of a a slot. The two parts are side by side and open to one another. The cross-section is the same as that of the connecting rod where the protrusion is attached but not elsewhere where the cross-section of the connecting rod is simply a circle.
The cross-section of the entrance 262 is the same as that of the passageway but slightly larger so that the connecting rod can be inserted without difficulty through the entrance. Similarly the cross-section of the passageway is slightly larger than that of the connecting rod where the protrusion is attached. The connecting rod can accordingly be moved longitudinally i.e parallel to the longitudinal axis of the passageway but, because of protrusion 252, it cannot be rotated.
However when the protrusion is beyond the end of the passageway, for example when it is outside the inner wing segment adjacent to wall 264b as illustrated in Figure 21A, the opening enlarges and the connecting rod can be rotated because the protrusion no longer prevents the connecting rod from doing so.
In Figure 21A, protrusion 252 extends to the side or in a direction parallel to the long-itudinal axis 20 of the fuselage. The protrusion will project in that direction when the outer and inner wing segments are interconnected. The protrusion is outside the passageway so that the connecting rod can be rotated subject however to the restraint to rotation imposed by the pivotal connection 254.

When the outer segment of a wing is to be removed from the aircraft, the steps for doing so are as follows: first, and with reference to Figure 19, the outer segment of the wing is separated from the inner wing segment only sufficiently to remove tongue 156 from panel 160.
The two segments cannot be completely separated at this time because the connecting rod cannot be drawn through the passageway for the reason that the protrusion in the connecting rod extends horizon-tally as illustrated in Figure 21A while the slot in the passageway extends vertically. In Figure 22, connecting rod 250 is shown in front of wall 264b of the inner wing segment 264.
The next step in the removal of the outer wing segment is to rotate the outer wing segment 260 one quarter turn counterclockwise in move the trailing edge of the outer segment downward to the position shown in broken lines in Figure 23. The outer segment is shown in broken lines and the entrance to the passageway 266 is shown in solid lines.
The latter solid lines coincides with the cross-section of the connecting rod which comes into alignment with the entrance of the passageway since the connecting rod, being connected to the outer wing segment, rotates with the wing segment. The connecting rod can then be drawn through the passageway thereby separating the outer wing segment from the inner segment.
When the outer wing segment is to be folded into contact with the side wall of the fuselage as illustrated in Figure 20, the steps for doing so are followed: the first step is the same as step one in the removal of the outer wing segment. The next step is to rotate the outer wing segment clock-wise one quarter turn in order to move the trailing edge of the wing segment upward. As the wing segment rotates so too does the connecting rod and pin 256 of pivotal connection 254. The pivotal connection now rotates about a vertical axis and allows the wing segment to fold back along a side wall of the fuselage as illustrated in Figure 20. A strap 300 or other restraint prevents the wing segment from swing back and forth while the aircraft is being towed.
It will be understood, of course, that modifications can be made in the structure of the aircraft of the subject invention without departing from the scope and purview of the invention as covered in the claims that follow.

Claims

I claim:

1. An amphibious aircraft having a fuselage provided with oppositely facing side walls and a pair of wings each having outer and inner segments, said inner wing segments being attached to said fuselage while said outer wing segments being selectively attachable to said inner wing seg-ment and detachable therefrom, said outer wing segments being selectively foldable relative to said inner wing segments from an inoperative position adjacent to said side walls of said fuselage to an operative position in which said outer wing segment extends outward from said inner wing segment and said outer and inner wing segments combine to support said aircraft when airborne.

2. The amphibious aircraft as claimed in claim 1 further including a connecting rod having a pair of pivotally interconnected components, one said component being attached to one of said inner and outer wing segments while the other said component being accommodated in a hollow in the other of said one inner and outer wing segments, said other component being selectively movable within said hollow from a first position in which said other component is removable from said hollow with resulting detachment of said inner and outer wing segments from one another to a second position in which said inner and outer wing segments are selectively folded together and unfolded.

3. The amphibious aircraft as claimed in claim 1 wherein each said inner and outer wing segments have walls which face one another when said inner and outer wing segments are attached, said aircraft further including a connecting rod having inner and outer components which are pivotally interconnected, one of said inner and outer components being attached to one of said inner and outer wing segments while the other of said inner and outer components is partly accommodated in a hollow formed in the other of said inner and outer wing segments and is partly outside said hollow, said hollow having a longitudinal axis and having: (i) an entrance from said facing walls of said other inner and outer wing segments, (ii) a passageway which commences at said entrance and extends to an end, said other of said inner and outer components having a protrusion while said entrance and said passageway have a slot in which said protrusion is adapted to slide, said slot terminating at said end, said entrance and said passageway being constructed to allow said other of said inner and outer components to slide in a direction parallel to said longitudinal axis of said passageway but said protrusion when in said slot preventing rotary motion of said other of said inner and outer components and when outside said slot, permitting rotary motion of said other of said inner and outer components.

4. The amphibious aircraft as claimed in claim 1 further including a tongue associated with one of said outer and inner wing segments, said tongue having an opening; a lever pivotally mounted to the other of said one outer and said inner wing segments; an arm having engaging means, pivotal movement of said lever causing movement of said engaging means into and out of said opening for selective connection and disconnection of said outer and inner wing segments.

5. The amphibious aircraft as claimed in claim 1 wherein said fuselage has a bottom wall having a longitudinally extending plane of symmetry, said bottom wall comprising: a pair of downwardly extending central walls which together define a generally V-shape and which extend downwardly and intersect at a lower edge which lies on the plane of symmetry, each said central wall having an upper edge which terminates at a vertical, downwardly extending second wall, said second walls and said central walls defining a tunnel, each said second wall extending downwardly to a third wall which extends normal to said plane of symmetry and which extends outwardly thereof and terminates at a fourth wall which extends upwardly and outwardly of said axis and terminates at a respective one of said side walls.

6. The amphibious aircraft as claimed in claim 4 wherein said fuselage has front and back walls and a conduit having an inlet at said front wall and an outlet at said tunnel, said conduit providing a passage for air which enters said inlet from front of said aircraft to flow to said tunnel.

7. The amphibious aircraft as claimed in claim 1 wherein said aircraft is provided with a retractable main landing gear comprising a pair of wheels each disposed adjacent to a separate said side wall; a compartment for removable accommodation of each said wheel;
a central gear provided with means for causing said central gear to rotate; a gear train activated by said central gear for causing said wheels to alternatively and simultaneously advance from said compartments and to retract into said compartments.

8. The amphibious aircraft as claimed in claim 1 wherein said aircraft is provided with a retractable main landing gear comprising a pair of main wheels each disposed adjacent to a separate said side wall; a central bevel gear having means for causing said central gear to rotate selectively in clockwise and counterclockwise directions; a pair of second bevel gears which mesh with said central gear and being on opposite sides of said central gear such that said second gears rotate in opposite directions to one another; a pair of third bevel gears, each of which meshes with a separate said second gear; a pair of fourth bevel gear, each of which meshes with a separate said third gear; a pair of first worm gears each of which is caused to rotate by a separate said fourth gear; a pair of second worm gears, each of which is caused to rotate by a separate said first worm gear; a pair of pinions each of which is caused to rotate by a separate said second worm gear; and a pair of racks each of which meshes with a separate said second worm gear and each of which causing a separate said wheel to alternatively advance and retract.

9. The amphibious aircraft as claimed in claim 1 wherein said aircraft is provided with a retractable nose gear having a front wheel and a wheel well for accommodating said front wheel, said nose gear comprising: an upper post mounted to pivot in said fuselage; a lower post adapted to swivel about said upper post and having means for selectively preventing such swivelling; a handle for causing said upper post to pivot from an active position in which said wheel is disposed outside of said fuselage for supporting a forward end of said fuselage to a passive position in which said wheel is disposed within said wheel well.