but the wings are still producing sufficient lift to support part of the weight. This has the same effect as a lower tyre pressure i.e. lower and wider range of speeds for aquaplaning.
Huh??? You've contradicted yourself if you re-read what you've written,
Wiz, notwithstanding that weight has nothing to do with aquaplaning speed anyway! (The contradiction in your "hypothesis, is on the one hand you are stating that during the initial touchdown the lesser weight on the wheels "
has the same effect as a lower tyre pressure", then you go on to say this equates to "
lower and wider range of speeds for aquaplaning.".
My impression has always been that the speed at touchdown is faster than it is towards the end of the landing roll.
Do you know something the rest of us don't,
Wiz??
Touching down firmly (a good idea at all times) puts all the load on the wheels and deploys the speed brakes in the shortest time
As
Cloud Cutter has pointed out, speedbrake deployment is dependant upon main wheel spin up.
DirtyPierre, the formula of 9 times the square root of the tyre pressure to give aquaplaning speed (in mph) was always the one I had used as well, but I seem to recall reading (somewhere) recently that there was now more of a range (something along the lines of 7-11) with 9 still the median.
Anyone else seen this reference?
Cloud Cutter, rubber reversion is the phenomenom that occurs when the water trapped between the wheels and the runway heats up (to form steam) and dissolves the rubber into smallish tacky "blobs", further reducing braking effectiveness through the tyre to pavement contact. Well that was my understanding of it, at least.
Anyway, avoid speeds around 80-90 kph in your car on days when it's p!ssing down - I experienced aquaplaning in my car several years ago (by not following my own advice
) and ended up off the freeway in a gully. It's a strange sensation, you can turn the steering wheel full lock both ways with just an index finger, and NOTHING happens....I just kept going straight ahead foot off the accelerator, at the SAME speed (until I hit the grass)
