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Old January 15th 08, 11:02 PM posted to rec.aviation.student,rec.aviation.piloting
Matt Whiting
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Default more confusion on cessna performance chart

terry wrote:
On Jan 15, 9:02 am, TakeFlight wrote:
Rolling resistance of tires?

Hard to say what Cessna's assumptions are, especially when they didn't
include their formula, just a data set.


I would think rolling resistance would be less at lower temperatures.
rubber softens at higher temps and gets a better grip. the data shows
the reverse , at lower temps for the same density altitude the
distance required is higher.


Stiff tire sidewalls are harder to flex and thus absorb more energy in
the process. This is why radial tires, even though they flex more, have
lower rolling resistance than bias ply tires. It isn't intuitive, but
it is reality.

Matt