Hard Landing Impact to Airplane Tires

Описание: A hard landing occurs when an aircraft or spacecraft hits the ground with a greater vertical speed and force than in a normal landing.

Landing is the final phase in flight, in which the aircraft returns to the ground. The average vertical speed in a landing is around 2 metres per second (6.6 ft/s); any greater vertical speed should be classed by crew as hard. Crew judgment is most reliable to determine hard landing, as determination based on recorded acceleration value is difficult and not advisable, partially because there is no recording of true vertical acceleration.

Hard landings can be caused by weather conditions, mechanical problems, overweight aircraft, pilot decision and/or pilot error. The term hard landing usually implies that the pilot still has total or partial control over the aircraft, as opposed to an uncontrolled descent into terrain (a crash).

Hard landings can vary in their consequences, from mild passenger discomfort to vehicle damage, structural failure, injuries, and/or loss of life. When an aircraft has a hard landing, it must be inspected for damage before its next flight.

Hard landings can cause extensive damage to aircraft if not carried out safely or properly. For example, on 20 June 2012, a Boeing 767 of All Nippon Airways landed with such force that a large crease formed in the aircraft's skin.
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An aircraft tire or tyre is designed to withstand extremely heavy loads for short durations. The number of tires required for aircraft increases with the weight of the aircraft, as the weight of the airplane needs to be distributed more evenly. Aircraft tire tread patterns are designed to facilitate stability in high crosswind conditions, to channel water away to prevent hydroplaning, and for braking effect.

Aircraft tires also include fusible plugs (which are assembled on the inside of the wheels), designed to melt at a certain temperature. Tires often overheat if maximum braking is applied during an aborted takeoff or an emergency landing. The fuses provide a safer failure mode that prevents tire explosions by deflating in a controlled manner, thus minimizing damage to aircraft and objects in the surrounding environment.

The four major manufacturers in aircraft tire manufacturing are the following according to a report by Pelmar Engineering in 2013:
1. Goodyear (United States)
2. Michelin (France)
3. Dunlop Aircraft Tyres (United Kingdom)
4. Bridgestone (Japan)