A traction control system and method are provided for electric vehicles with at least one drive wheel powered by an electric drive motor to maintain optimum maximum traction while the vehicle is driven on the ground. The traction control system includes drive means capable of transmitting torque through a vehicle drive wheel and controllable to move the vehicle over a ground surface. A preferred drive means is an electric motor designed to move the vehicle at desired ground speeds in response to operator input. Operator input requests a desired speed, and the system determines drive wheel torque required to produce the desired speed and provides maximum current to produce maximum torque to drive the vehicle with optimum traction at the desired speed. The system uses constant feedback to find maximum current corresponding to torque required for an inputted speed request to automatically control traction in any electric powered vehicle.

An aircraft electric taxi system diagnostics and prognostics evaluation method, including receiving, with a computer, an electronically recorded first performance parameter of a first electric taxi system of a first aircraft during a taxi operational event at an airport; and comparing the first performance parameter with a first performance factor statistical model generated in response to the first performance parameter and first comparative performance parameters; and calculating a first performance parameter difference based on the comparison.

An aircraft hubcap/wheel cover which uses ambient airflow (120 mph-175 mph) to rotate wheels on the landing gear of an aircraft accomplished by using slightly protruding slats, blades, scoops or other air capturing shapes, (once the landing gear has been lowered). These air capturing shapes are integrated as part of the hubcap/wheel cover during manufacture and are directly determined by ground speed applicable to that aircraft with the ultimate purpose being tire longevity. The wheel cover hubcap is a single piece design and has no moving parts.

An aircraft hubcap/wheel cover which uses ambient airflow (120 mph-175 mph) to rotate wheels on the landing gear of an aircraft accomplished by using slightly protruding slats, blades, scoops or other air capturing shapes, (once the landing gear has been lowered). These air capturing shapes are integrated as part of the hubcap/wheel cover during manufacture and are directly determined by ground speed applicable to that aircraft with the ultimate purpose being tire longevity. The wheel cover hubcap is a single piece design and has no moving parts.

An identification system and method are provided for aircraft equipped with electric taxi systems for autonomous ground movement that enables airport ground personnel and others outside the aircraft to safely and easily identify the aircraft moving on ground surfaces at an airport as equipped with a pilot-controlled electric taxi system and to distinguish these aircraft from aircraft not moved by electric taxi systems. The identification system may be mounted with nose or main landing gear drive wheels supporting the electric taxi system. The identification system includes an identifying lighting system with lighting elements of a selected number, shape, color, or arrangement positioned on at least a visible face of one or more landing gear wheels. Automatic or manual controls may actuate the identification system to identify electric taxi system-equipped aircraft when the aircraft are moved with the electric taxi system or are stopped.

An efficient system and method are provided wherein aircraft may be retrofitted with non-engine drive means controllable to power landing gear wheels to move the aircraft autonomously during ground movement without engines or tow vehicles so that existing landing gear structures are employed to achieve force distribution and load transfer. Non-engine drive means capable of powering a landing gear wheel to move the aircraft during taxi are integrated into existing landing gear designs so that excess drive forces are transferred and distributed through previously evaluated and certificated landing gear structures, including tow fittings, determined to be capable of handling such forces, which eliminates changes to the landing gear and facilitates retrofit and certification. Engines-off taxi technology can be rapidly designed and developed to be retrofitted on existing aircraft nose and/or main landing gear and then efficiently certificated.

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.

A method for controlling an aircraft taxiing system, comprising the steps of: generating a nominal load command (Comm_nom); generating an acceleration setpoint (Cons_a); implementing, in parallel with the generation of the nominal load command, a processing chain (7) comprising a regulation loop (Br), the regulation loop (Br) having for its setpoint the acceleration setpoint (Cons_a) and for its command an acceleration command (Comm_a), the acceleration command being converted into an acceleration load (Eff_a), a maximum load threshold being equal to the maximum of the acceleration load (Eff_a) and a minimum load threshold (Seuil_min); and generating an optimised load command (Comm_opt) equal to the minimum of the nominal load command and the maximum load threshold.

An electrical system for an aircraft with an electric taxi system (ETS), the electrical system may include at least one traction motor, a DC link and at least one traction-motor bidirectional DC-AC converter interposed between the at least one traction motor and the DC link. An engine-driven power source may be configured to provide DC power to the DC link or extract DC power from the DC link. A battery unit may be configured to provide DC power to the DC link or extract DC power from the DC link. An adaptive power controller may be interconnected with the power source, the battery unit and the at least one traction-motor bidirectional DC-AC converter and configured to regulate voltage of DC power delivered to the DC link.

A method is provided for improving aircraft engine operating efficiency during flight in aircraft driven on the ground by electric taxi systems that extends engine warm up and cool down time during ground operations without increasing the time an aircraft spends on the ground. Aircraft are driven by electric taxi systems between landing and take off with the main engines simultaneously maintained at throttle setting for time periods that ensure even and symmetrical heating or cooling for all engine components. When the aircraft reaches a location where idle or take off thrust is required before take off, engine thrust may be increased without the adverse effects of differential thermal expansion of engine components during flight. Aircraft engines may be designed to rely on electric taxi operation and extended warm up and cool down times without delaying push back or taxi-in or otherwise negatively impacting airport operations.