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Old 16th Aug 2007, 05:50
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Barry Bernoulli
 
Join Date: Nov 2006
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I have heard of this problem, but been cautioned about it being a problem if brakes are applied after take-off on aircraft with large, high-profile tyres. On touchdown you have the runway surface applying a change in angular momentum to the tyre (at the outside of the diameter) and the tyre bead transmitting a lesser change in angular momentum to the rim. If you apply the brakes after take-off, the opposite applies; you have a rapid change in angular momentum of the braked rim, and an even larger change in angular momentum of the high profile tyre being absorbed by the bead. Thus, we did not apply brakes before retracting gear after take-off.

The tyres had creep marks. I never saw anything written in the manuals about it.

I accept that where landing gear retracts across the lateral axis, the gyroscopic effect may be worse that the tyre creep issue. But then I've never seen an aircraft with large, high profile (high flotation) tyres that are retracted laterally. All pure speculation on my part in the absence of published warnings/cautions.
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