Looking at that landing clip the tyres do get some punishment, Wonder how often they change them?
Aircraft tyres take one hell of a lot of punishment .... they sit at 30-odd thousand feet for hours on end .. at temperatures of -42 C (ish) and very low outside pressures so the tyre expands a lot ... the aircraft descends and the tyre gets "squeezed" back to normal size .. but doesn't warm up much ... it is hanging in the breeze with zero rotational speed when the aircraft touches down at it goes from zero to mega-lots rpm .. the aircraft is doing around 150 mph remember ... almost instantaneously... it doesn't quite do it though .. which is why you get the puff of smoke as the tyre "skids" on spin-up.
The reason they use dry nitrogen to inflate aircraft tyres is also dead simple ... normal air contains moisture .. at altitude that condenses out into water at the bottom of the tyre, which then freezes... and doesn't melt in the descent ... this is a large weight which would cause extra load on the "spin up" of the tyre as well as a HUGE balance problem that could actually damage the undercarriage/bogies
Tyres are changed when worn down to a specified marker, on the Herc it was the centre tread gone, but are then sent for retreading. A tyre would do about 100-150 landings under "normal" conditions. Rough strips/shale/shingle and sand blowing onto runways in the middle east wore them out faster
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Topic: Some nice ground to air video (Read 1669 times)