Abstract: An aircraft brake temperature control system (BTCS) 100 for controlling a temperature of a brake 220 of a landing gear 201 of the aircraft 200. The BTCS 100 includes a controller 110 configured to cause at least one fluid moving device 230, 231, 232 to drive a flow of fluid onto the brake 220, selectively in one of a plurality of modes, to control the temperature of the brake 220. The BTCS 100 may be incorporated into an aircraft system 1000 with at least one fluid moving device 230, 231, 232, wherein the aircraft system is on an aircraft 200.

Abstract: An apparatus, system and method capable of providing a stabilizing drive system for a robotic vehicle. The apparatus, system and method may include at least a robot body base; at least two drive wheels within the robot body base; a processing system having non-transitory computing code associated therewith which, when executed by the processing system, causes to be driven the at least two drive wheels; and a plurality of ball casters within the robot body base, wherein the ball caster are positioned relative to the robot base and to the at least two drive wheels so as to lower a center of gravity of the robot and provide stabilization of the driving.

Abstract: A feedback system senses a steering position of a nose wheel assembly for an aircraft. The nose wheel assembly has a first element rotatably associated with a second element about an axis, and the rotational position of the first element relative to the second element corresponds to the steering position of the nose wheel assembly. The feedback system includes a first magnetic field sensor fixedly positioned relative to the first element and configured to sense a first element orientation. A second magnetic field sensor is fixedly positioned relative to the second element and configured to sense a second element orientation. The feedback system further includes a controller programmed to determine the steering position of the nose wheel according to the sensed first element orientation and the sensed second element orientation.

Abstract: A steering apparatus may comprise a steering collar, a first linear actuator, a first drive gear, a crankshaft, and a sun gear, wherein the sun gear is disposed within the collar, wherein the first drive gear is fixed to the crankshaft and coupled to the sun gear such that the collar rotates about the sun gear in response to rotation of the crankshaft, wherein the first linear actuator is coupled between the crankshaft and the collar.

Abstract: One embodiment is an aircraft including a main body, a plurality of propulsion assemblies, and a plurality of hinges, wherein each of the plurality of propulsion assemblies is rotatably coupled to the main body using a hinge from the plurality of hinges. In an example, the aircraft includes four motor support arms and each motor support arm rotatably couples a specific propulsion assembly to a specific corresponding hinge on the main body of the aircraft and increases a span of the aircraft when the aircraft is in the flight configuration and reduces the footprint of the aircraft when the aircraft is in a storage configuration.

Abstract: Aircraft landing gears include at least one wheel, an electric taxiing system including an electric taxiing motor, brakes capable of slowing down or stopping the rotation of the wheel, and a cooling system for cooling the electric taxiing motor and the brakes. The cooling system includes ventilation means capable of mixing a first air flow originating from the brakes and a second air flow originating from outside the landing gear and of ventilating the electric taxiing motor with a mixture of the two air flows.

Abstract: A nose-wheel steering system is disclosed. In various embodiments, the system includes an actuator; a strut; and a gearing mechanism operably coupling the actuator to the strut, the gearing mechanism including a steering collar attached to the strut, and idler gear engaged with the actuator and a pinion having a first gear engaged with the idler gear and a second gear engaged with the steering collar.

Abstract: A helicopter tug apparatus for loading, transporting, and unloading a helicopter landing skid includes a plurality of landing skid loading units. The loading units are arranged to support the landing skid, and each of the loading units includes a skid cradle with a plurality of tug rollers configured to engage the landing skid. The loading units each include a drive track, and at least one motor for operating the skid cradle and the drive track. The rollers are reverse synchronized with the drive track, such that when the drive track moves the loading unit under the landing skid, the tug rollers turn in reverse to avoid placing lateral force on the landing skid.

Abstract: The invention relates to a method for controlling an aircraft taxi system, comprising the steps of: generating a traction command (Com) to control an electric motor of a wheel drive actuator; detecting whether or not an external brake command, intended to control braking of the wheel via the brake, is generated; if an external braking command is generated, producing a predetermined minimum command (Cmp) to control the electric motor so that the drive actuator applies a strictly positive predetermined minimum motor torque to the wheel during braking; detecting whether a speed of the aircraft becomes zero and, if so, inhibiting the predetermined minimum command (Cmp) so that the drive actuator applies zero torque to the wheel.

Abstract: The present disclosure is directed to a unique design of multi-purpose wheels for use in multi-purpose vehicles capable of operating in different transportation modes in different mediums such as flying mode and driving mode. Advantageous design of multi-purpose wheels and vehicles of the present disclosure allow for easy and convenient change in transportation mode of such vehicles without need for any special purpose transportation infrastructure. In one aspect, a multi-purpose tool includes a first set of blades configured to enable an object to which the multi-purpose tool is attached to operate in a first mode of transportation; a second set of blades configured to enable the object to operate in a second mode of transportation; and an engagement mechanism coupled to the first set of blades and the second set of blades for switching operation of the object between the first mode of transportation and the second mode of transportation.

Abstract: A landing gear controller (120) to control extension and retraction of a landing gear for an aircraft, the landing gear controller (120) configured to cause, during an aircraft take-off or landing procedure, a landing gear extension and retraction system (110) to perform only a first portion of a landing gear extension or retraction process, on the basis of a status of the aircraft and prior to receiving a command for the landing gear to be extended or retracted.

Abstract: An unmanned aerial vehicle (UAV) having a plurality of arms and a land/air drive assembly attached to each arm. The land/air drive assembly includes (i) a multi-speed motor assembly; (ii) a propeller having a first diameter and driven by the motor assembly at a first speed; and (iii) a ground drive wheel having a second diameter greater than the first diameter and driven by the motor assembly at a second speed slower than the first speed. A drive assembly orientation actuator is positioned between each arm and each drive assembly, wherein the orientation actuator is configured to, on command, rotate the drive assembly between a flight position and ground drive position approximately perpendicular to the flight position.

Abstract: An unmanned vehicle having a launch configuration and one or more operational configurations. In the launch configuration, one or more engines resides within an engine bay. The unmanned vehicle is generally shaped like a projectile and can be launch from any tube-shaped deployment system using an initial propulsor. The engine bay can be opened, and the engines can be moved into a generally external position with respect to the engine bay for operation of said engines. In some embodiments, the one or more engines can pivot to direct thrust in multiple directions. In some embodiments, the unmanned vehicle includes flight control surfaces to further improve the flight characteristics of the vehicle.

Abstract: A landing gear controller (120) to control extension and retraction of a landing gear for an aircraft, the landing gear controller (120) configured to cause, during an aircraft take-off or landing procedure, a landing gear extension and retraction system (110) to perform only a first portion of a landing gear extension or retraction process, on the basis of a status of the aircraft and prior to receiving a command for the landing gear to be extended or retracted.

Abstract: A clutch arrangement for between an engine and a propeller of a drivetrain of a roadable aircraft. The arrangement includes an engine shaft, a propeller shaft, a stationary clutch arrangement housing, and an engagement member which is rotationally locked to and axially slidable relative to propeller shaft. The engagement member includes a first engagement structure for engaging a corresponding engagement structure associated with the engine shaft for setting the clutch arrangement in a propeller propulsion mode, in which rotational propulsion torque is transmitted from the engine shaft to the propeller shaft via the engagement member. The engagement member further includes a second engagement structure for engaging a corresponding engagement structure associated with the clutch arrangement housing for setting the clutch arrangement in a propeller locked mode, in which the propeller shaft is rotationally locked to the clutch arrangement housing by means of the engagement member.

Abstract: In one or more embodiments, the ground roll assist system is based on the electric in-wheel motors integrated with the main landing gear of an aircraft and linked to the aircraft control system. It is well known that modern electric motors possess superior torque density characteristics, potentially exceeding best in class internal combustion engines by more than an order of magnitude. Furthermore, electric motors performance is generally thermally limited, which makes it possible to achieve even higher performance for a short period of time.

Abstract: Braking systems and methods for an electrical vertical takeoff and landing aircraft are provided. A braking system may contain a pilot control device, brakes, wheels, sensors, and a controller. Pilot controls the pilot control device to transmit information to the controller such that the aircraft will slow down.

Abstract: A multi-modal vehicle includes a frame, a rotor pivotally mounted to the frame, the rotor including a first position and a second position circumferentially spaced from the first position, and a motor coupled to the rotor and configured to rotate the rotor, wherein, when the rotor is disposed in the first position, the rotor is configured to generate lift when actuated by the motor, wherein, when the rotor is disposed in the second position, the rotor is configured to engage a surface to transport the vehicle when actuated by the motor.

Abstract: An aircraft includes a body defining an interior compartment configured to hold at least one of a passenger and a payload, a battery system, a plurality of arms coupled to and extending from the body, and a plurality of propulsion devices configured to provide thrust to fly the aircraft. Each of the plurality of propulsion devices is coupled to a respective one of the plurality of arms. The plurality of propulsion devices are powered by the battery system. Each of the plurality of propulsion devices is selectively pivotable about at least one axis. The plurality of propulsion devices include at least one of (i) counter rotating ducted fans and (ii) ionizing electrode engines.

Abstract: The current technique provides an unmanned vehicle that is capable of travelling in the air, on the ground and/or in the water. The driving force of the unmanned vehicle is provided by at least one propelling module that includes a motor, a shaft and a propeller. The propelling module is coupled to a chassis. The chassis includes one or more support elements that each couples to one or more aileron member. An aileron member is configured to tilt with or about the support element to change fluid flux about the aileron member and thus change a position of the propelling force.

Abstract: An aircraft landing gear bogie beam including first and second ends and a mounting bearing for connection to an aircraft landing gear main strut between the ends. Each end has a respective axle, and each axle defines a wheel mounting portion on each side of the bogie beam. The bogie beam is arranged to enable the first and second axles to each pivot relative to the bearing about a respective longitudinal axis of the bogie beam by an amount that is sufficient to place a wheel rim of a wheel assembly in contact with the ground in the event of a tyre of the wheel assembly deflating.

Abstract: A flying object according to the present invention has been developed to have a plurality of rotor blades or jet engines, and to reduce the risk of a crash even if any one of the rotor blades or jet engines is damaged. The flying object comprises: a flying fuselage; a plate-shaped protection member having a plurality of through-holes formed on the same circumference thereof; a driving means arranged in each of the through-holes; and a tilting means for tilting each of the driving means, or a rotating means for rotating the protection member around a shaft member, wherein the diameter of the protection member, the interval between the rotational axes of the rotor blades facing each other, the length of the shaft member, and the length of the flying fuselage have a predetermined ratio.

Abstract: The present invention includes an apparatus for preventing aircraft rollover upon a water landing comprising: a deployable first and/or second boom affixed by a first end to the aircraft and capable of deployment substantially perpendicular to a longitudinal axis of the aircraft; and a first and/or second air bladder attached to a second end of the first and/or second boom, wherein the first and/or second air bladders are configured to inflate when an aircraft lands in the water, wherein deployment of the first and second boom and air bladder prevents aircraft rollover upon water landing; or a deployable keel affixed by a first end to the aircraft and capable of deployment substantially perpendicular to a longitudinal axis and opposite a rotor of the aircraft upon a water landing, wherein the keel is sized to prevent aircraft rollover upon deployment; or both.

Abstract: The invention provides a drive system for rotating a wheel of an aircraft landing gear. The drive system includes a motor operable to rotate a drive pinion, and a driven gear adapted to be mounted to the wheel. The drive system has a first configuration in which the drive pinion is capable of meshing with the driven gear to permit the motor to drive the driven gear and a second configuration in which the drive pinion is not capable of meshing with the driven gear. The drive system includes a linear positioning actuator for moving the drive pinion relative to the driven gear. The positioning actuator has a first end and a second end, the first end having a pivotal connection with a pivot axis spaced at a fixed distance from an axis of rotation of the driven gear, and the second end having a pivotal connection with a pivot axis spaced at a fixed distance from an axis of rotation of the drive pinion.

Abstract: A drone includes a surrounding cage which can be disassembled from a propeller-carrying internal base. In another aspect, a drone includes at least one fastening clip which attaches arcuate external ribs to a periphery of a central and internal frame, whereafter the fastening clip can be removed for disassembly of the ribs from the frame. Yet another aspect provides a flying drone employs a fastening clip including a snap fit and a generally U-shaped body. A further embodiment has a flying drone with at least one light externally mounted adjacent a periphery of a central propeller-carrying base, located between a pair of external ribs.

Abstract: A parking robot for a transportation vehicle having a holding device for firmly holding a wheel of the transportation vehicle and housing at least one drive installation on two opposite sides. The drive installation has a height-adjustable running gear having at least one parking robot wheel and adjusts the holding device relative to the at least one parking robot wheel between a lowered and a raised position. The parking robot autonomously moves to a receiving position on the wheel of the transportation vehicle, in which receiving position the holding device firmly holds the wheel, and by adjusting the holding device to the raised position by the running gear, raises the firmly held wheel of the transportation vehicle relative to the respective parking robot wheels.

Abstract: A turnaround monitoring system and method are configured to monitor a turnaround of an aircraft at an airport. The turnaround monitoring system and method include receiving, by a turnaround analysis control unit, turnaround data regarding the aircraft at the airport, and determining, by the turnaround analysis control unit, a turnaround status of the aircraft based on the turnaround data.

Abstract: An assistance vehicle designed for supplying electrical energy to an electric taxiing device of an aircraft landing gear when the aircraft is moving over the ground. The assistance vehicle includes an autonomous energy source, a connector enabling it to be coupled to the aircraft and to electrically power the electric taxiing device. When an assistance instruction comprising the aircraft position is received, the assistance vehicle moves in an autonomous manner so as to reach the position of the aircraft, is automatically connected to the electric taxiing device when the assistance vehicle reaches the position of the aircraft and switches into freewheeling mode. When the assisted move has finished, the assistance vehicle is separated from the electric taxiing device and switches back into tractor mode. Thus, the electrical power supply system of the aircraft is simplified by externalizing the electrical supply of the electric taxiing device.

Abstract: A nose landing gear system is disclosed. In various embodiments, the nose landing gear system includes an electric motor; a hydraulic pump connected to the electric motor; a gearbox connected to the electric motor; and a clutch configured to mechanically couple the gearbox to a steering collar.

Abstract: The invention provides an engagement method for engaging a first gear element with a second gear element, at least the second gear element being mounted to move between a meshing position and a disengaged position by means of an actuator. The engagement method including a step of driving at least one of the gear elements in rotation so as to establish a non-zero difference in speed of rotation between said gear elements, and a step of controlling the actuator to perform the following in succession: moving at least the second gear element towards the meshing position; on detecting contact between the gear elements, stopping the movement of the second gear element; and on detecting an ideal angular position for engaging said gear elements, moving the second gear element as quickly as possible into the meshing position.

Abstract: A method for disinfecting a water system of an aircraft includes letting-in of hot water at an inlet of the water system by a first ground service unit; flushing the hot water from the inlet, through water pipes of the water system, to an outlet of the water system; and letting-out of the hot water at the outlet, by the first ground service unit or a second ground service unit; the hot water being flushed into the inlet and out of the outlet over a predefined disinfection period; and the hot water being provided at the inlet via a continuous-flow heater of the first ground service unit.

Abstract: The invention relates to a method for controlling the torque of a drive device (1) for rotating wheels (2) of an aircraft comprising actuators for selectively driving rotating wheels of the aircraft to ensure its movement on the ground, comprising the step of regulating a torque generated by the drive device according to a torque setpoint (4) issued by the pilot. According to the invention, the method involves the step of generating, as long as the torque setpoint is not sufficient to guarantee a stable movement speed of the aircraft, a replacement torque setpoint (5) to allow the aircraft to move at a stable speed, and substituting the replacement torque setpoint for the torque setpoint generated by the pilot.

Abstract: A dolly for placement beneath a landing gear of an aircraft that enables transport of the aircraft without rolling the tire of the aircraft. The dolly includes a platform for a tire to rest on and a channel for positioning the tire. The dolly includes a winch for translating the dolly and aircraft tire relative to each other such that the landing gear is brought to rest on the platform, and one or more stops for securing the aircraft landing gear with respect to the dolly. Once positioned, the dolly can be used while transporting the aircraft, either by hand pushing, a hand towbar, a motorized tug with a towbar, or other mode. The dolly is useful for moving aircraft in tight spaces and is also useful for transporting aircraft with damaged landing gear or flat tires.

Abstract: A monitoring system for an aircraft has sensors that are used to sense the presence of objects around the aircraft for collision avoidance, navigation, or other purposes. At least one of the sensors may be configured to sense objects around the aircraft and provide data indicative of the sensed objects. The monitoring system may use information from the sensor and information about the aircraft to determine an escape envelope including possible routes that the aircraft can follow to avoid colliding with the object. The monitoring system may select an escape path based on the escape envelope and control the aircraft to follow the escape path to avoid collision with one or more objects.

Abstract: A method for engaging a first gear element with a second gear element is provided. The second gear element is mounted to be mobile between a meshing position and a position of disengagement using an actuator. The method includes driving one or more of the first and second gear elements in rotation to form a non-zero rotation speed difference between the first and second gear elements and controlling the actuator to successively displace the second gear element to the meshing position, and when an intermediate position of the second gear element is detected, stop the displacement of the second gear element, and when an angular position of engagement of the first and second gear elements is detected, displace the second gear element to the meshing position.

Abstract: Some aspects relate to systems and methods for fly-by-wire reversionary flight control including a pilot control, a plurality of sensors configured to: sense control data associated with the pilot control, and transmit the control data, a first actuator communicative with the plurality of sensors configured to receive the control data, determine a first command datum as a function of the control data and a distributed control algorithm, and actuate a first control element according to the first command datum.

Abstract: A ground manoeuvering device comprises a housing with a fastening device for the skid, a hydraulic apparatus as well as an outer wheel and an inner wheel on two aligned horizontal axles on the hydraulic apparatus, respectively one on the inside and one on the outside beside the skid. The hydraulic apparatus comprises an extendable piston and an engagement shaft with a lever attached in a swivellable manner. When the lever is rocked, the piston is extended from the hydraulic apparatus and thereby lifts the housing vertically upwards. The engagement shaft is aligned in the wheel running direction and the lever extends, in the operating state, in the wheel axle direction of the outer wheel. In addition, the lever comprises a tread section, in order to raise the fastened skid onto the two wheels using the hydraulic apparatus while standing conveniently beside the helicopter repeatedly stepping with the foot on the tread section.

Abstract: An aircraft landing gear assembly having a bogie beam pivotally coupled to a support member, and a pitch trimmer assembly including a pitch trimmer actuator configured to exert a biasing force in a first direction and a bias force transmission assembly configured to receive the biasing force in the first direction and bias the bogie beam towards a predetermined neutral position relative to the support member irrespective of the initial position of the bogie beam.

Abstract: A taxiing system for an aircraft is presented. The taxiing system comprises a hydraulic accumulator configured to receive an increase in hydraulic pressure from a hydraulic motor; a system inlet valve configured to provide hydraulic flow from a hydraulic system of the aircraft to the hydraulic motor; a flow control valve system comprising a plurality of valves configured to direct hydraulic flow between the hydraulic accumulator and the hydraulic motor; and the hydraulic motor connected to wheels of the aircraft and configured to drive or stop the wheels using movement of hydraulic flow in the taxiing system.

Abstract: Techniques related to video coding with a multi-pass prediction mode decision pipeline.

Abstract: A system for landing and locomoting on a surface of a structure comprises an unmanned aerial vehicle having a plurality of independently controllable thrusters and an undercarriage including a frame with wheels at corners. The undercarriage further includes a plurality of bars pivotally coupled at respective first ends to the frame and coupled at respective second ends to the unmanned aerial vehicle; wherein the unmanned aerial vehicle is operative to differentially activate the plurality of thrusters so as to tilt with respect to the frame of the undercarriage and to cause a net resultant force on the undercarriage to locomote on the surface of the structure.

Abstract: A method of engaging a drive system with a rotating wheel of an aircraft landing gear is disclosed. A motor is operated to apply torque to a pinion so the pinion rotates. An engagement command is issued to an actuator at an engagement time, and the actuator operates the actuator in response to the engagement command to move the pinion from a neutral position to a contact position in which it contacts a rotating driven gear at an initial contact time, the rotating driven gear being mounted to a rotating wheel of an aircraft landing gear; then after the initial contact time operating the actuator to move the pinion further to a meshing position where the pinion meshes with the driven gear. A centre-to-centre distance between the pinion and the driven gear reduces as the pinion moves to the contact position and to the meshing position.

Abstract: A drone includes a surrounding cage which can be disassembled from a propeller-carrying internal base. In another aspect, a drone includes at least one fastening clip which attaches arcuate external ribs to a periphery of a central and internal frame, whereafter the fastening clip can be removed for disassembly of the ribs from the frame. Yet another aspect provides a flying drone employs a fastening clip including a snap fit and a generally U-shaped body. A further embodiment has a flying drone with at least one light externally mounted adjacent a periphery of a central propeller-carrying base, located between a pair of external ribs.

Abstract: A method of engaging a drive system with a rotating wheel of an aircraft landing gear is disclosed. A motor is operated to apply torque to a pinion so the pinion rotates and moved from a neutral position to a contact position in which it contacts a rotating driven gear at an initial contact time, the rotating driven gear being mounted to a rotating wheel of an aircraft landing gear. After the initial contact time the pinion is moved further to a meshing position where the pinion meshes with the driven gear. A centre-to-centre distance between the pinion and the driven gear reduces as the pinion moves to the contact position and to the meshing position. The driven gear contacts the pinion in a series of impacts as the pinion moves from the contact position to the meshing position, each impact induces a spike in electromotive force or angular velocity at the motor.

Abstract: A device for managing the mechanical energy of an aircraft, having a light system, includes a support defining a guide; at least one control lever for varying the mechanical energy of the aircraft, mounted moving through the guide; and at least one position sensor detecting the position of the control lever in the guide, configured to create position information for the position of the control lever in the guide intended to be sent to a flight control unit of the aircraft. The device also includes at least one light strip extending on the support along at least part of the travel of the control lever in the guide; and a control unit of the at least one light strip, configured to display at least one light indication at least at one given point of the lighted position ramp calculated as a function of a movement context of the aircraft.

Abstract: Systems and methods for controlling an unmanned aerial vehicle within an environment are provided. In one aspect, a system comprises one or more sensors carried on the unmanned aerial vehicle and configured to receive sensor data of the environment and one or more processors. The one or more processors may be individually or collectively configured to: determine, based on the sensor data, an environmental complexity factor representative of an obstacle density for the environment; determine, based on the environmental complexity factor, one or more operating rules for the unmanned aerial vehicle; receive a signal indicating a desired movement of the unmanned aerial vehicle; and cause the unmanned aerial vehicle to move in accordance with the signal while complying with the one or more operating rules.

Abstract: A drive system for rotating a wheel of an aircraft landing gear is disclosed including a motor operable to rotate a drive pinion via a drive path; and a driven gear adapted to be attached to the wheel so as to be capable of rotating the wheel. The drive system has a drive configuration in which the drive pinion is capable of meshing with the driven gear to permit the motor to drive the driven gear via the drive path. The drive path comprises a first compensating gear mounted on a common drive shaft with the drive pinion so as to be capable of rotating in tandem with the drive pinion, and a second compensating gear which is meshed with the first compensating gear. One of the drive pinion and the driven gear comprises a roller gear having a series of rollers arranged to form a ring, each roller being rotatable about a roller axis, and the other of the dive pinion and the driven gear comprises a sprocket.

Abstract: A landing gear (0) for an aircraft comprising a wheel (R), a system (1) for rotationally driving the wheel that is mobile between a clutched position and a safety position by passing through a declutched position, and a manoeuvring system (3) to displace the driving system (1) between its declutched and clutched positions. The gear comprises an elastic return (4) for returning the driving system (1) to its safety position and first and second abutments (51a, 52a) that are separated as long as the driving system (1) is away from its safety position and in contact with one another when the driving system (1) is in safety position. The first and second abutments (51a, 52a) oppose the passing of the driving system (1) from its safety position to its declutched position when the abutments are in contact with one another.

Abstract: In one aspect, there is disclosed a taxi vehicle comprising a chassis having a coupler to connect to a coupling location of a craft and a set of wheels with at least one electric motor coupled to the set of wheels. The taxi vehicle can include a fuel cell coupled to the at least one electric motor and a battery coupled to the fuel cell. The battery can be configured to supply peak power demand to the at least one electric motor to start moving the craft. The battery can receive charging from the fuel cell when not supplying peak power demand while the fuel cell supplies power to the at least one electric motor to continue moving the craft.

Abstract: An aircraft landing gear comprising: a shock-absorbing main leg having a sprung part for attachment to an aircraft and an un-sprung part including a slider and an axle carrying at least one wheel, the wheel having a toothed ring gear; a drive transmission mounted externally on the sprung part, or on the un-sprung part, of the main leg, the drive transmission having at least one motor and a drive pinion for meshing with the toothed ring of the wheel; and an actuator for lifting the drive transmission into and out of driving engagement with the toothed ring and for maintaining the driving engagement as the landing gear deflects during a ground taxiing operation. Also, a method of operating the aircraft landing gear.