Re: Best handling/stickiest tires?
- From: jobst.brandt@xxxxxxxxxxxxxxxxxx
- Date: 29 Aug 2008 16:18:11 GMT
Peter Cole wrote:
I suspect most of us wouldn't count it as a slick - I'd say it's
a tyre with insignificant tread, not no tread - but it doesn't
really matter that much.
Is something like this
a slick in your terms too? (I'm happy for it to be so :-) )
I'd call that slick, with sidewall decoration, and I'm happy to
ride it (I have a pair on my Raleigh Royal). Slicks are OK on
cycles, as the contact patch is so small and the pressure so high
- we'd need well over 100MPH to aquaplane.
As I said, don't fly commercial air if you believe that. These
aircraft touch down at close to 200MPH with slicks on rainy runways
while braking hard. Your perception of aquaplaning with round
cross section tires is imagined, rather than from experience.
As far as I know, most/all aircraft tires have deep circumferential
grooves to channel water.
How do you know they "channel water"? The Motorcycle zig-zag widely
spaced grooves do not channel water either.
That tire is not the one that puts on the brakes nor carries most of
the weight of the aircraft.
In that statement you'll find:
# The investigation shows that new tires meet the stopping distance
# requirements regardless of tread design. Tires 80 to 90% worn,
# however, require a minimum of four grooves to stop within the
# desired distance.
That sounds contradictory but aside from that, it's a fairly old test
KC135 not being a current commercial aircraft. If you look at the
tires of a 373 or 747 you'll note that the grooves are about 6" apart,
and too small to carry significant water and therefore constitute 6"
The reason this works is that the tire is a round cross section and
has a contact area with the runway in the shape of a canoe (pointed
ends) the shape that dissipates water to the sides, unlike automotive
tires that have a rectangular contact patch and dissipate water
forward... if possible.
That car tires displace water in a broad sweep forward can be
appreciated by the huge wave of water that rises over a car when it
hits standing water on a road. It is the broad flat front of
automotive tires that cause hydroplaning. Conventional tire tread
does little to prevent that and all the fancy tread patterns with
sweeping diverging grooves are BS.