Allan W wrote:
It is fine and well in a car to brake or change down gears, but with an automatic coach the brakes heat up very quickly and start to fade if used to slow a bus over miles of downhill road. All coaches are fitted with speed limiters, restricting the top speed to 60 mph and it is often safer to allow the limiter to slow the bus rather than suffer brake fade by travelling downhill constantly braking.
Did I miss something here? How can a limiter slow a vehicle if engine braking and the brakes aren’t enough to stop it?
Allan W wrote:
I had a car in front of me which had just overtaken and it went through the camera faster than I was travelling. The camera did not flash the car which I believe was doing around 65mph but it did flash my coach (empty at the time) which according to my tachograph was doing 57mph.
The gatso got you and let the car go because gatsos make use of a crude method to differentiate between vehicle classes, determined by the amount of radar signal returned (the vehicle class can be confirmed by cross-referencing the registration in the database).
Allan W wrote:
Further to that, they then have to carry on the journey with brakes not working to full effect due to overheating.
Do they really have to carry on? Would it not be safer to pull over for a few minutes to allow the disks to cool in case an emergency stop is required?
As I understand it, the only way to help prevent brake fade is to go down the hill much slower; spreading the potential energy over more time means less instantaneous power, hence cooler disks. Am I right?
Also, slowing and changing down gear allows the engine to do even more of the braking effort.