[Vwdiesel] Fwd: mileage

[Dave Cook]

--- On Mon, 11/30/09, Kurt Nolte <syncronized_turbo at yahoo.co.uk> wrote:
> I've had a few occasions to really like the "brakes engage
> when you lose 
> air pressure" safety feature too. That kind of inherently
> built in 
> safety feature is part of why I love air brakes on anything
> heavier than 
> a "light" duty truck.
> -Kurt

This comment reminded me of something I've wondered for awhile.  I was a school bus driver for several years.  Most of the busses had normal, hydraulic brakes.  But we had a couple larger busses used for sports and such that had air brakes.  In Kansas, you have to have another endorsement beyond the CDL to drive air brake vehicles. 

I could never figure out why air brakes were better on the bigger busses than hydraulic.  Seemed like the mechanics were always needing to dink with something in they systems because the tank wouldn't work right, or there was a problem with one of the cylinders, or something.  Whereas on the regular busses, the only brake issues ever were typical replacing pads/rotors occasionally.  

I can see on a semi tractor/trailer where air brakes would be beneficial, IE being able to hook up the trailer, and have brakes without the problem of bleeding hydraulic brakes or something like that.  

But why on a larger bus would they be better?  Just seems like more possibility of things to go wrong.