Patent Description:
Visit any large urban area today and you almost immediately experience transportation problems. Short rides using surface transportation (bus, car, taxi) can take longer than walking the same route and distance at a leisurely pace. Subways and trains are overcrowded and correspondingly unpleasant. Population growth and urban migration models and predictions make clear that the problems will only get worse.

In consequence, there is considerable activity to devise transportation alternatives that reduce the load on existing systems. One approach takes advantage of the almost entirely untapped urban space above us - the sky above streets and buildings.

Current work and research is principally being conducted at a frenetic pace by tech, peer-to-peer ride-sharing, and aircraft companies, to devise and design aircraft suitable for use in an urban "air taxi" system. Airbus, Boeing, Google, Pipistrel, NASA, and others have thrown their hats into the ring. Without exception, their early and prototype designs derive from existing vertical takeoff and landing (VTOL) drone and helicopter designs, including tilt wing, ducted fan, helicopters, cyclogyros, tiltrotors, and so forth. The express intention is that the aircraft be able to utilize building tops as skyports. Highly layered urban traffic control areas for such use are also contemplated.

We may see the realization of a fully functional urban air mobility system within a decade. New, high-powered electric motors and power management controllers for aviation are available. New air traffic management hardware and artificial intelligence systems to control individual aircraft and provide safe separation from other aircraft in the system are being studied. Pilotless and Optionally Piloted Aircraft (OPA) and other types of autonomous aviation controls are also being developed. However, proposed aircraft designs for use in urban environments are, without exception, of the VTOL type.

Unfortunately, VTOL aircraft known to date, including electric aircraft, have numerous disadvantages, most notably in creating high noise and consuming significant energy on takeoff and landing. Accordingly, it may be desirable to provide a more conventional aircraft to achieve the same objectives of VTOL design for an air taxi or urban air mobility system.

An alternative to VTOL aircraft are short takeoff and landing (STOL) aircraft. These aircraft are common; their primary advantage over conventional aircraft is that they are able to operate from short runways. They have been widely used for military transport since the <NUM> and as "bush" planes in remote wilderness areas. The shortcoming of STOL aircraft is that the landings are generally ill-adapted for urban environments.

What is needed, therefore, is an improved STOL aircraft capable of quiet and energy efficient operation in an urban environment, using building-top runways of reasonably short length. <CIT> discloses an aircraft with vertical take-off and landing, in particular, to an aircraft with hybrid or electric drive, intended to be used for air transport of passengers and freights without requiring landing runways. The disclosed aircraft has a fuselage and extensible wings located on either side of the fuselage; it has a cabin of an aerodynamic shape extending laterally and backwards, respectively, with two spars provided therebetween with a gap, as well as a modular propelling system consisting of two multiple propellers mounted on the cabin, located in front of the wings, on either side of the fuselage, and one multiple propeller located within the said gap, mounted between the two said spars. <CIT> discloses a retractable three-wheeled undercarriage for aircraft comprising a front medial wheel and two side wheels is operated from two transverse shafts connected to a common drive, one shaft causing the front wheel to be moved in the longitudinal plane of the machine and the other shaft actuating the side wheels which are moved in a plane transverse to the machine. A transverse shaft carries at its ends frames, each supporting an engine and a gear quadrant, with which mesh level gear wheels. Rotation of the shaft thus causes the shafts, which are carried in bearings infixed frames, to rotate about longitudinal axes and extend or retract the wheels, which are on offset portions of the shafts. <CIT> discloses a method and apparatus in which an aircraft system such as the landing gear system or braking system is operated at least partially under power provided by a generator driven by the wheels of the landing gear. <CIT> discloses a device has a motor unit driving an input of a transmission unit e.g. planetary gearset, where an output of the transmission unit is cooperated with a landing gear for displacing the landing gear, during the rotation of the motor unit.

The aircraft of the present invention includes a novel type of landing gear that makes it possible for the aircraft to achieve short takeoffs and smooth, short landings in approximately <NUM> meters or less. The application for the inventive aircraft and its advanced landing gear is for an all-electric STOL plane capable of high cruise speeds (up to <NUM>/hr) (<NUM> mph) in nearly all weather conditions.

Acceleration and deceleration are expressed in units of g-force, or "g". The derivative of acceleration with respect to time (or the change in the rate of acceleration/deceleration) is known as "jerk", and it is measured in g/sec.

Most individuals easily tolerate acceleration/deceleration rates over <NUM> without alarm or discomfort if the rate is gradual, smooth, and uninterrupted. A commercial airliner landing has fairly low deceleration but high jerk rates. Jolts and bumps even at a low <NUM> feel jarring and alarming for some people.

To accommodate a wide range of individual comfort levels, takeoffs and landings must be reassuringly smooth and free of whiplash, jolts, let-ups, shakes, and bumps. A straightforward and effective way to achieve short distance takeoffs is by simply accelerating, or driving the plane to takeoff speed. The inventive aircraft employs a driven wheel that is positioned far aft of the center of gravity (COG) to prevent tip back. However, because the drive wheel is back from the COG, the plane rotates less easily at takeoff. To balance the desired performance characteristics, rotation is forced at the end of the takeoff run using motorized front landing gear that effectively drives the nose up at takeoff. The same motorized mechanism is used to soften the landings.

STOL landings are also challenging. The landing distance must not only be short, but the plane must consistently hit a very narrow touchdown mark, all while coming in fast and decelerating hard in choppy conditions. Even with advanced robotic controls, this cannot be achieved while following a smooth, jolt-free path. How, then, is it done?.

The inventive aircraft includes sensors that envelope the plane and precisely measure the distance to the ground as the plane passes into the touchdown zone. When the plane passes over the touchdown zone within ± <NUM> meters (<NUM> in) of a target height, motorized landing gear is rapidly deployed and closes the distance between the plane and the ground. The wheels touchdown solidly, but do not bounce the plane. The front landing gear touches well ahead of the COG, and the entire weight of the plane is immediately shifted off the wing and onto the wheels without any concern for nosing over during hard braking. The front wheels disposed on the outer ends of the landing gear struts take over to decelerate the plane and the legs gently lower the body of the plane to a resting position.

Other novel features which are characteristic of the invention, as to organization and method of operation, together with further objects and advantages thereof, will be better understood from the following description considered in connection with the accompanying drawing, in which preferred embodiments of the invention are illustrated by way of example. It is to be expressly understood, however, that the drawing is for illustration and description only and is not intended as a definition of the limits of the invention. The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to, and forming part of, this disclosure. The invention resides not in any one of these features taken alone, but rather in the particular combination of all of its structures for the functions specified.

The invention will be better understood and objects other than those set forth above will become apparent when consideration is given to the following detailed description thereof. Such description makes reference to the annexed drawings wherein:.

Referring first to <FIG>, wherein like reference numerals refer to like components in the various views, there is illustrated therein a new and improved STOL Aircraft, generally denominated <NUM> herein.

Preferred embodiments of the aircraft <NUM> achieve short takeoffs and landings whether piloted or unpiloted, as in remotely controlled drone flight. In the preferred embodiments having the shortest takeoff and landing distance, the avionic systems control critical landing gear movements and the overall landing gear configuration to coordinate gear positions with one or more of the following conditions, including height, airspeed, ground speed, and runway position.

In accordance with the present invention the STOL aircraft <NUM> comprises a central fuselage <NUM> that supports left and right wings <NUM> and <NUM>'. Empennage (tail wing assembly) <NUM> includes elevators <NUM>. The empennage may be any of a high-wing, low-wing, or mid-wing design.

Fuselage <NUM> in preferred embodiments deploys a globular cockpit <NUM> and can provide or be extended to provide a cargo bay. The fuselage includes an axially disposed aft frame member <NUM> that supports the tail assembly at the distal end 111b, with the proximal end 111a joined at the common wing junction above the globular cockpit.

In preferred embodiments the front landing gear <NUM> is deployed in the landing process to absorb energy, and both the front and rear landing gear configurations and operation enable short takeoff distances.

The front landing gear <NUM> preferably comprises a pair of struts <NUM>/<NUM>' on opposing right and left sides of the fuselage <NUM>, each with the drive mechanism shown in <FIG>.

The preferred modes of takeoff and landing are further enabled by the configuration of the fuselage and other heavy components that position the center of gravity (COG) between the front and rear landing gear.

The two front landing gear struts <NUM>, <NUM>' and the rear landing gear strut <NUM> are each driven by a separate motor, preferably electric.

Front landing gear <NUM> and rear landing gear <NUM> are connected to the globular cockpit <NUM>. As shown in <FIG> and <FIG>, the front landing gear <NUM> includes a pair of linear struts <NUM>/<NUM>' coupled to the fuselage or cockpit <NUM> by a rotary joint <NUM> at a proximal end with the distal end supporting at least one wheel <NUM>/<NUM>' in rotary engagement.

The rear landing gear <NUM> deploys a linear strut <NUM> and includes a wheel <NUM> at a distal end, and a pivotal connection to the fuselage <NUM> or cockpit <NUM> using a rotary joint or coupling <NUM>. Wheel <NUM> is driven by an in-line motor (not shown) to accelerate the aircraft for takeoff. It is preferably operatively coordinated with the movement of the front landing gear <NUM> by a Ground-Air-Made-Short (GAMS) landing gear <NUM>.

Successful short runway landings require that the aircraft wheels touch down in a narrow range in the landing zone. The requirements may be on the order of a tenth of a second for the minimum potential runway length. The means to achieve such exactitude is to have the landing gear "reach" for the ground at the exact moment needed, which means that the landing gear is actively rotated downwardly in relation to landing conditions data relating to height over the runway, position in the landing zone, ground speed, vertical speed, and so forth. As the aircraft nears the runway, the avionics control system rotates the landing gear down to engage the ground before the gear would otherwise contact the ground on a glide path for decelerating the plane.

The other part of the solution is to eliminate wing loading and transfer weight onto the landing gear to maintain high deceleration through wheel braking. As speed drops, high deceleration is difficult to achieve aerodynamically. It is a key requirement, therefore, to initiate and produce as much forward horizontal deceleration in the air and maintain that deceleration during landing.

The GAMS landing gear <NUM> employs a motor <NUM> to position the front landing gear <NUM> and rear landing gear <NUM>. The same assembly includes a disc brake <NUM> to dissipate the vertical sink energy. The elongate and relatively long landing arms or struts <NUM>/<NUM>' and <NUM> are dimensioned to accommodate a wide variety of approach conditions and to ensure that the aircraft does not bounce or porpoise on touchdown and rollout.

The front landing gear <NUM> deploys the wheel supporting struts <NUM> downwardly when they are in a range of distance from the ground that they will touch the ground as they descend. The contact is sensed so that the wings can then be actively and rapidly unloaded of lift (using, for instance, spoilers), so vertical deceleration is absorbed by the forward landing gear brakes as well as the wheel brakes that absorb horizontal deceleration.

A long wheelbase (the distance between front wheels <NUM> and rear wheel <NUM>) when the gear is deployed may be advantageous for acceleration on takeoff, but it is disadvantageous for rotation on takeoff. Wheeled vehicle acceleration and deceleration requires a long wheelbase with the center of gravity near the midline. The need for easy and quick embarkation introduces further challenges. An aircraft with a long wheelbase cannot take off without powered assistance. Thus, the same GAMS power unit is employed to force the aircraft to rotate for takeoff.

In a preferred embodiment, a plurality of electric motors provide land and flight propulsion.

In another preferred embodiment, at least one landing gear wheel drives the plane on the ground to the lift off speed. The strut portion of the gear is then driven to provide upward thrust at lift off. The upward thrust from the landing gear adds to the lift provided by wings. The GAMS mechanism of <FIG> is the preferred mechanism to provide this function.

The preferred embodiments of the aircraft <NUM> are expected to have a runway length requirement of <NUM> meters or less.

The GAMS power unit <NUM> is illustrated in detail in <FIG>, in which a motor <NUM> supported on a yoke <NUM> has a shaft <NUM> that is supported by a ball screw joint <NUM>. The rear landing gear strut is configured as a form <NUM> lever having a rotary joint coupling as the fulcrum. The end of the shaft 1540a is rapidly urged (in the direction of arrow <NUM>) against the arm <NUM> of the rear wheel strut <NUM>, rotating the strut and forcing the wheel <NUM> downward. The motor <NUM> rotation is stopped by the disc brake <NUM>.

On landing, shaft <NUM> moves in the reverse direction, counter rotating the motor to absorb the energy of landing as the strut <NUM> moves upwardly, with the energy also absorbed by the disc brake <NUM>. Landing energy can also be absorbed by one or more conventional shock absorbers, such as various forms of springs, as well as active suspension systems that may deploy electromagnetic actuators, as well as combinations thereof. Such energy absorbing systems can have any combination of linear and non-linear energy absorption.

The GAMS power unit also operates to lift and deploy the forward wheels <NUM>/<NUM>' by rotating struts <NUM>/<NUM>'. The forward wheel struts <NUM>/<NUM>' each have a lateral shaft <NUM>/<NUM>' coupling to rotate as the hinged coupling <NUM> is rotated by the ball screw actuator arm <NUM> that couples in turn to the ball joint <NUM> that receives the threaded shaft <NUM> connecting to the motor <NUM>. Other motors drive the propellers, landing gear, control surfaces, and wheels for ground propulsion, and are powered by a modular battery <NUM> capable of fast interchange for quick turnaround.

An energy or power source <NUM> provides energy to power the motors <NUM>/<NUM>'. One or more primary motors which drive one or more propellers <NUM>/<NUM>', which may be two motors <NUM> and <NUM>' mounted on the left <NUM> and right <NUM>' wings. A modular battery <NUM> is a preferred power source. The modular battery <NUM> may be mounted to the fuselage <NUM> or aircraft so that it can be jettisoned rapidly in the event of fire or any other impending hazardous state or condition. The power source <NUM> can be a sort of solid state battery as well as a fuel cell and a source of hydrogen for the fuel cell. Alternatively, the power source can be liquid fuel that drives an internal combustion motor, which in turn generates electricity by driving an electric dynamo-machine, i.e., a generator.

It should also be appreciated that it is preferable that the COG is disposed between the front landing gear <NUM> and rear landing gear <NUM> by the central placement of the passenger seats and the power supply.

The battery is preferably supported by translating it longitudinally within the airframe to adjust the COG with respect to the load from passengers or freight. Placement of battery, cargo containment means (and other heavy components) within the fuselage <NUM> and cockpit <NUM> properly positions the COG.

An optional cargo bay is preferably a module that forms part of the outer skin on the fuselage behind the cockpit.

Looking next at <FIG> there is shown the front landing gear and rear landing gear modules, each isolated and physically removed from the airframe and shown in a fully retracted configuration, as they appear when the aircraft is in midflight cruise operation.

Referring now to <FIG>, details of an embodiment of the landing gear structures and operational drive systems are shown. Reference numbers from the earlier views for like elements are not carried over here; instead new reference numbers are provided for similar earlier identified structures as well as for newly identified detail features.

<FIG> illustrates that in an embodiment the front and rear landing gear assemblies structurally connect to, and operate in relation to, the aircraft airframe <NUM> so as to form a system suited for STOL operations. The airframe <NUM> (for convenience arbitrarily shown here as a section of indeterminate size) supports and connects to a front landing gear module <NUM> and a rear landing gear module <NUM>. The airframe includes an interior surface or side <NUM>, a longitudinally-oriented center slot <NUM>, and left and right (port and starboard) sockets <NUM>, <NUM>, respectively. The front landing gear module <NUM> is operatively and pivotally connected to the airframe and its interior side <NUM> through the port and starboard sockets <NUM>, <NUM>.

The front landing gear module includes port and starboard struts or legs <NUM>, <NUM>, respectively. Each leg includes, at a distal end, a fetlock <NUM>, <NUM>, pivotally connected to the leg at a fetlock pivot <NUM>, <NUM>; a front cradle <NUM>, <NUM> (latter not showing) pivotally coupled to the fetlock at a cradle pivot <NUM>, <NUM> (latter not shown); a cowling <NUM>, <NUM> pivotally connected to the front cradle at a cowling pivot <NUM>, <NUM>; and terminating in driven wheels <NUM>, <NUM>, rotatingly disposed on axles <NUM>, <NUM> (port side not visible). Drive systems/motors <NUM>, <NUM> are provided for each wheel (again, port side not visible). Clamshell doors <NUM>, <NUM> may be provided to enclose the wheels in flight.

Each front landing gear strut <NUM>, <NUM> (port and starboard) terminates as an inboard rotatable deployment/retraction axle <NUM>, <NUM>, each axle disposed through an airframe socket, port and starboard, <NUM>, <NUM>, respectively. Each axle is driven by a lead screw <NUM>, <NUM> pivotally connected to the axle with a pintle/gudgeon coupling <NUM>, <NUM>. The coupling and axle form bell cranks <NUM>, <NUM>.

Electric motors <NUM>, <NUM> are mounted to the airframe interior side <NUM> with a trunnion/bracket mount <NUM>, <NUM>, which extend their respective lead screws to retract the corresponding strut or retract their respective lead screws to deploy or extend the respective strut. Motor trunnions pivot at pivot points <NUM>, <NUM> (latter not clearly visible). Motor control for both the deployment/retraction of the landing gear struts and for their respective drive wheels resides in system avionics described more fully below.

In the embodiment shown in <FIG>, the rear landing gear module <NUM> includes a rear leg strut <NUM> having a driven rear wheel <NUM> rotatingly coupled to the strut through an assembly that includes an axle <NUM> disposed through a rear wheel fork <NUM>. A rear wheel drive system <NUM> is operatively coupled to the rear wheel. The rear wheel fork <NUM> is pivotally coupled to a rear wheel gimbal <NUM> through a fork/gimbal pivot <NUM>. In turn, the gimbal <NUM> is pivotally coupled to the rear strut <NUM> through a gimbal/strut pivot <NUM>. A rear wheel fairing <NUM> partially encloses the rear wheel, the enclosure selectively completed by a tail fairing door 368a.

The rear landing gear, like the front landing gear, is driven by a strut drive system, <NUM>, which in embodiments is an electric motor. It is mounted on the airframe inner side with a motor trunnion <NUM> pivotally mounted on a trunnion bracket <NUM>. The motor drives a lead screw <NUM> that engages a rear strut clevis <NUM> to pivot the strut on a rear strut shaft <NUM> disposed in a trunnion carriage <NUM>. Motor control again resides in avionics control systems, described more fully below.

Operation of the landing gear modules just described may be seen by referring now to <FIG>, <FIG> and <FIG>, where there is shown a range of the dynamically adaptive landing gear configurations during landing and takeoff sequences.

Thus, and looking first at <FIG> and concurrently referring back to <FIG>, there are shown configurations of the aircraft during a takeoff sequence. The sequence in <FIG> proceeds over time from right to left. In the rightmost schematic image <NUM> of the inventive aircraft, the landing gear can be seen to be in a taxiing configuration <NUM>. Both front and rear wheel steering are enabled and the wheels may be selectively driven, as needed. In the middle view <NUM>, the aircraft landing gear is in its ground roll configuration <NUM>, similar to the taxiing configuration except that the front landing gear has limited steering and the rear wheel is powered and its steering is locked. As the plane reaches and then exceeds a predefined landing-gear-enhanced rotation speed, <NUM>, the landing gear control system rotates the front landing gear downwardly into a rotation configuration <NUM> to drive the aircraft nose up, increasing the angle of attack and dramatically and rapidly increasing lift. The rotation configuration <NUM> is shown more clearly in <FIG>.

Looking next at <FIG>, and then back at <FIG> and <FIG>, there are shown a sequence of landing gear configurations corresponding to a typical landing as might be accomplished using the advantageous dynamically active landing gear of the present invention. <FIG> shows the developing configurations. In a cruise flight <NUM> the front and rear landing gear struts are fully retracted and folded underneath the airframe in a cruise flight configuration <NUM>. Then as the aircraft reaches a late stage of final approach <NUM>, the front landing gear is activated and deployed into an approach configuration <NUM>. This may be characterized as a "reaching forward" configuration. Before and as this configuration is achieved, flight system controls align the aircraft and place it on an approach vector and glide slope that will enable it to land safely on the STOL runway. Then, when the aircraft passes through a target cloud <NUM>, both front and rear landing great struts are rapidly extended downwardly. The target cloud referred to herein is a virtual envelope enclosing a predetermined volume of airspace defined by a range of possible safe landing positions above and close to the runway threshold on the approach when the aircraft meets certain parameters (e.g. ground speed). In embodiments, the target cloud may be a cuboid airspace having <NUM> x <NUM> x <NUM> meter dimensions. When the aircraft position <NUM> is detected as being in the target cloud, the dynamically active landing gear "reaches" down <NUM> toward the runway to more quickly bring the front and rear landing gear wheels into contact with the runway. The aircraft then rapidly slows to a roll out and taxiing configuration <NUM> with the front landing gear struts fully extended forward and the rear landing fully extended aft <NUM>.

<FIG> show configurations intermediate those of <FIG>. <FIG> shows the aircraft landing gear configuration as the target cloud is reached. <FIG> shows the landing gear as the energy of the vertical sink is absorbed by the landing gear. <FIG> shows the configuration as the landing gear reaches the taxiing configuration.

<FIG> show an alternative landing gear assembly in landing gear configurations corresponding in sequence to the landing gear configurations shown in <FIG>. Preliminarily, it should be noted that the salient alternative features include a rear landing gear wheel <NUM> rotatable about a pivot at the distal end of the rear landing great strut <NUM> so as to enhance the "reaching" feature during landing. The front landing gear wheels have a similar feature, enabling them to pivot and extend downwardly as the plane approaches the runway.

In preferred embodiments, the avionics system controls the landing gear deployment in coordination with the propeller and wheel drives for the precise movement with respect to location and speed to fully enable the STOL advantages. Such an avionics control system may be capable of remote or drone control, as well as autonomous or semi-autonomous control. More pertinently, the landing gear system control may be pilot controlled or, in a pilotless/autonomously controlled embodiment, controlled with on-board system avionics or remotely controlled from a centralized control system.

<FIG> shows the conditions monitored and actions taken by the control systems during a takeoff sequence <NUM>. Cabin conditions, passenger safety checks, scheduling taxi and takeoff movements according to skyport/airport and area traffic, and the like are understood and assumed, and therefore not set out here. Rather, the focus is on the role played by the aircraft landing gear in facilitating a short field takeoff. Mention should be made, however, that all pre-flight activities are handled either by system controls alone or in combination with actions by flight personnel. For instance, in preparation for flight, the aircraft doors are closed and the plane shifted from a loading configuration to a taxi configuration, and the cabin and any passengers are readied for flight. The landing gear and flaps are configured for ground roll <NUM>, and plane then taxis toward the runway <NUM>. It then merges onto the runway and is aligned with the runway centerline <NUM>. Full power is applied to the propellers <NUM>. Drive wheel power is employed to supplement acceleration as needed <NUM> until rotation speed is reached <NUM>. At that point, wings and flaps are deployed in a customary manner according to wind conditions, aircraft loading, and available runway length <NUM>. Concurrently or immediately after, the front landing gear struts are driven downwardly so as to push the aircraft nose upward <NUM> to an optimal angle of attack to shift loading onto the wings to get into and through ground effect and into free flight at higher altitude <NUM>. The landing gear is pulled up (wheels up) <NUM>, and the plane is then configured <NUM> for optimal climb performance according to the climb requirements needed to clear obstacles, to remain clear of other traffic in the urban Traffic Control Area, and to achieve level flight altitude. The landing gear is then fully retracted into cruise flight configuration <NUM> and the aircraft proceeds to its destination.

<FIG> shows the conditions monitored and the actions taken by the aircraft control systems as the aircraft approaches its destination and during the landing sequence at the destination <NUM>. When the aircraft enters an airport/skyport traffic pattern <NUM> its speed and flap configuration are adjusted <NUM>. When cleared for landing and vectored onto final approach, the aircraft turns to a final approach heading and is aligned with the runway centerline <NUM>. Aircraft sensors then lock onto the landing target (the above-described target cloud) <NUM> and the front landing gear is extended outwardly <NUM> and readied for dynamic adjustments immediately preceding touchdown. Further fine adjustments are made in response to air and wind conditions and aircraft flight conditions (loading, groundspeed, wind direction, current flight control configurations, etc.) <NUM>. Full flaps are deployed as needed <NUM>. Sensors in the front landing gear struts measure the closing distance to the target cloud <NUM> and when the aircraft is within a predetermined distance, precision distance measuring sensors are engaged <NUM>. These sensors search for and signal the control system when the aircraft is within the target cloud <NUM>. In response, the landing gear is immediately deployed downwardly to "reach" for the ground <NUM>. Landing great struts move independently to compensate for aircraft roll or pitch <NUM>. The process continues to touchdown <NUM>, at which time spoilers are actuated <NUM> and loading is shifted entirely from the wings to the landing gear <NUM>. Deceleration continues <NUM>, brakes are applied <NUM>, and vertical sink energy is absorbed and adjusted to maximize landing smoothness and minimize jerk <NUM>. Once a sufficiently low speed is achieved, the landing gear is moved into a taxi configuration <NUM>. The aircraft will quickly reach maximum deceleration <NUM>, and it will continue a short roll at taxi speed <NUM>. The flaps are retracted <NUM>, and the plane taxis off the runway <NUM>, ready for unloading and for preparations for a next flight.

Advantages of embodiments of the invention arise from the preferred exclusive use of electric motors for all the drive mechanisms to improve reliability and to decrease maintenance, as this eliminates fuel and hydraulic lines, which are prone to leaks and failure over time. Such leaks can create slip hazards on airstrips and reduce an aircraft's ability to decelerate safely in a limited space.

The foregoing disclosure is sufficient to enable those with skill in the relevant art to practice the invention without undue experimentation.

Claim 1:
A STOL aircraft (<NUM>) comprising:
a fuselage (<NUM>) having a port and a starboard side;
a pair of opposing fixed wings (<NUM>, <NUM>') being at least one fixed wing coupled to said fuselage and extending laterally from each of said port and said starboard side;
one or more propellers (<NUM>, <NUM>') coupled to at least one of said wings or said fuselage to provide axially directed thrust to propel said aircraft forwardly;
one or more motors (<NUM>, <NUM>') to drive said propellers;
at least one power source (<NUM>) coupled to said one or more motors to supply energy to said one or more motors ; and
three or more retractable and deployable landing gear modules (<NUM>, <NUM>) coupled to one or more of said fuselage and said wings and operative to rotate during landing to absorb vertical sink energy of said aircraft and to reduce shock to aircraft occupants, said landing gear modules including a front and a rear landing gear module, the front and rear landing gear modules being operatively coupled to said fuselage, each of said front and rear landing gear modules including at least one rotatable landing gear strut (<NUM>, <NUM>', <NUM>) with a wheel (<NUM>, <NUM>', <NUM>) disposed on its distal end, the wheel of the rear landing gear being powered;
a control system for controlling said landing gear motors to deploy and retract said front and rear landing gear struts;
landing gear motors (<NUM>) for driving said front and said rear landing gear struts independently; and
sensors configured to measure aircraft flight condition and position data, including airspeed, groundspeed, and position in relation to a runway and provide measurements to the control system;
wherein the aircraft center of gravity (COG) is disposed between said front and said rear landing gear module, and the front landing gear module being configured to rotate towards the ground during a takeoff run pushing a nose of the aircraft upward, and
wherein said control system is configured to rotate one or more of said landing gear struts in response to aircraft flight condition and position data.