A wear amount estimation method calculates a shearing force of each rib based on an average grounding pressure of each rib of an aircraft tire; calculates a wear energy of the aircraft tire based on the shearing force; and estimates the wear amount of the aircraft tire based on the wear energy and a wear resistance showing a relationship between a predetermined wear amount. The information related to the aircraft includes an internal pressure of the aircraft tire. The average grounding pressure of each rib is calculated based on the internal pressure and a wheel load applied to the aircraft tire.

A tire performance monitoring system including: a tire monitoring device configured to obtain, values indicative of a tire parameter of a tire over a time period, the tire monitoring device comprising a local memory configured to store a performance coefficient corresponding to performance of the tire; and a processing system configured to determine a tire performance characteristic based on the values and the performance coefficient.

A method of determining a tire performance characteristic of a tire. The method includes determining that a remote memory, remote from a tire monitoring device associated with the tire, is unavailable, and the remote memory is configured to store a performance coefficient of the tire corresponding to performance of the tire during a first time period. Where the remote memory is unavailable, the method includes either calculating the performance coefficient at a remote device or, obtaining, using the remote device, the performance coefficient from a local memory of the tire monitoring device. The method includes obtaining, using the remote device and from the tire monitoring device, a plurality of values indicative of a tire parameter of the tire during a second time period, and determining, at the remote device and based on the plurality of values and the performance coefficient, the tire performance characteristic.

A method of determining a tire performance characteristic of a tire including querying, using a processing system, a memory as to a presence of a first set of values indicative of a tire parameter of a tire in the memory, and determining, using the processing system, that the first set of values is insufficient to determine the tire performance characteristic of the tire, The method includes performing steps, using the processing system, comprising one or more of providing an indication that a second set of values indicative of the tire parameter is required to determine the tire performance characteristic of the tire, and retrieving, from the memory, a performance coefficient of the tire corresponding to performance of the tire associated with the first set of values, and determining, based on the performance coefficient, the tire performance characteristic of the tire.

A method of determining a tire performance characteristic of a tire. The method includes obtaining, using a processing system, a performance coefficient of the tire corresponding to performance of the tire during a first time period, wherein the performance coefficient is based on a first plurality of values indicative of a tire parameter over the first time period. The method includes obtaining a second plurality of values indicative of the tire parameter over a second time period, and determining, based on the second plurality of values and the performance coefficient, the tire performance characteristic.

An aircraft tire monitoring system including a processor, and a data carrier having machine readable instructions that, when executed, cause the processor to, based on a plurality of sets of values indicative of tire parameters of aircraft tires, each set of values corresponding to an aircraft comprising a plurality of the aircraft tires, perform operations including determining a remedial action associated with each set of values. The operations include determining a priority associated with the determined remedial actions, and generating, based on the determined remedial actions, a list of aircraft, the list of aircraft ranked based on the determined priority of remedial action. The operations include causing a display device to display the list of aircraft, such that aircraft with a relatively higher priority remedial action are shown higher up the list on the display than aircraft with a relatively lower priority remedial action.

A pneumatic tire having a carcass and a belt reinforcing structure, the belt reinforcing structure comprising: a zigzag belt reinforcing structure formed of a strip of reinforcement cords, the strip of reinforcement cords being inclined at 5 to 30 degrees relative to the centerplane of the tire extending in alternation to turnaround points at each lateral edge, wherein the strip of cords is formed from two different cords made of different materials.

A method of monitoring the pressure of a tire of an aircraft is disclosed including taking two or more pressure readings from the tire at different times; calculating an estimated deflation rate based on the pressure readings; and calculating a time for the tire to deflate to a reference pressure level based on the estimated deflation rate. Two or more temperature readings are each associated with one of the pressure readings, and the estimated deflation rate is calculated by normalising each pressure reading based on its associated temperature reading and a common reference temperature to obtain a temperature-normalised pressure reading, and calculating the estimated deflation rate based on the temperature-normalised pressure readings. The estimated deflation rate is compared with a threshold, and a warning provided if the estimated deflation rate exceeds the threshold.

A rotorcraft having an airframe, the airframe carrying at least one rotor that contributes to providing the rotorcraft with lift and/or propulsion, the rotorcraft having at least one undercarriage. The at least one undercarriage comprises at least one inclined wheel undercarriage, the inclined wheel undercarriage having an undercarriage leg carrying at least one axle, the at least one axle carrying at least one wheel, the at least one wheel not being in contact with any other wheel, the at least one wheel presenting positive or negative camber when the at least one wheel touches the ground and independently of forces exerted by said airframe on the inclined wheel undercarriage.

A remaining tire tread depth management system includes a remaining tire tread depth measurement device configured to measure a remaining tread depth of at least one of aircraft tires mounted on an aircraft, a tire wear amount estimation device configured to estimate a wear amount of all of the aircraft tires mounted on the aircraft including the aircraft tires, and a tire management server configured to estimate a remaining tread depth and a number of available flight times of all of the aircraft tires in accordance with measurement data output from the remaining tire tread depth measurement device and estimation data output from the tire wear amount estimation device.