Cruise control

I have. There's not a car made that can overpower its brakes. And many modern ones - especially autos - will partially kill the engine power if the brakes and throttle are pressed together.

The handbrake only has a tiny amount of braking power, roughly one third of the front brakes.

The car in question is rather old.

If the cruise control pulls a cable to operate the throttle (older vehicles are like this) then just remove that cable, the cruise control will then be unable to work under any circumstances, or just remove the plug to the motor.

+1. Brakes should be capable of stopping at at better than 1 g on a dry road. Your car can manage 1 g acceleration?

No chance.

True, but I was influenced already by what happened to me. All too often we are relying on "should work" or "should have worked..." as the case may be.

If not prepared, then the brain can easily get paralised in panic mode.

Didn't suggest anything of that sort. I wan't there! The story came up with CC because he told the 999.

Handbrakes today are merely a parking brake. Not an emergency brake as once was, since the advent of dual circuit footbrakes.

Even on my old Rover - over 30 years old - 'resume' does nothing below about 30 mph. Certainly won't do anything when parking.

If you car is remotely modern, the throttle is drive-by-wire anyway, so disbling the cruise control is pretty pointless: these days CC is a simple as an extra switch on the column stalk and setting it enabled in the engine ECU.

Besides... All this about how cruice control can be 'controlled'... It does not take into account that such control can fail. When systems fail, then the failed part of the system can not be controled by the system which has failed. Like it or not.

It's not impossible to design something like this failsafe. Especially since doing so isn't costly.

Let's face it - an ordinary throttle mechanism can jam in the fully open position. Much easier to make electronics simply stop doing anything if they fail.

Let me quote Rumsfeld then: "There are unknown unknowns.."

No, but you can mitigate risk and make it more safe than old fashioned throttle cable.

Agree with the sentiment that nothing is truly failsafe.

Such as...

CC should only work when button is pressed - Button not pressed CC should disengage below 20 mph - didn't work CC should disengage when using brakes - didn't work

I can only think of some radio interference as there will be strong RF within airport parking.

There is also driver error.

In your case a faulty TPS (for example) can give unintended acceleration, absolutely nothing to do with cruise control.

How are you certain it was cause by a fault in the CC?

Or an idle valve deciding to open. With injection cars, and air leak to the plenum can cause an increase in idle speed. More than enough to make an auto do more than creep.

But of course you have to stand on them hard and stop the car. If you just use them to get down to (say) 70 mph in the hope that the problem will clear itself, they will overheat and fade quite quickly, and then be no use at all.