Jim Henderson wrote:
> 
> Um, no, the brakes don't do the same - if you have disc brakes, the 
> brakes stop the wheels when fully engaged (I don't have drum brakes so I 
> can't comment on those).  

Yes, also on drum brakes. But why on earth would you engage brakes
fully, if you're not trying to stop the car as quickly as possible?

> Conversely, by downshifting, you increase the 
> engine revs and the wheels are not locked - they still turn.

Yes, if you'll do it carefully enough (see the similarity to brakes?)
:). It's possibly a bit easier to be carefully enough, since the maximum
braking power is very limited.

And yes, I actually managed to found one +point to engine braking - with
FWD car it practically ever won't spin the car, since rear wheels won't
lock.

> Now, when you're on dry pavement, the wheels normally don't lock because 
> the car's momentum overcomes the friction on the brakes, bringing you to 
> a gentle (or sometimes less-than-gentle) stop.  

Either you're having really bad brakes (repair them!) or you're not
anymore engaging them fully, when driving on dry pavement (so why to do
it on ice?).

> On ice, though, it takes 
> less friction of the brake pads against the wheel to stop the wheels 
> because it takes less to overcome the friction of the wheel against the 
> ground.

Yes, the scale is smaller, but it's still there.

> So it's easier to lock the wheels up and skid.

Definedly.

> Jim

-Aero

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