Quote Originally Posted by niky View Post
I am not disagreeing with you in regards to the Barr testimony, let's be clear. I like the fact that he found a single point of failure, rather than previous studies which had to come up with very convoluted failure modes (which were very unlikely)

What I am saying is this: The brakes will still function. What is happening is that at the beginning of SUA, since the over-ride function and the throttle controller have a common failure point, according to the study, the brake over-ride doesn't work. We agree on this. But on the initial brake application, the brakes themselves should work. If the driver does not sufficiently slow the vehicle down, or does not exert full braking, the brakes will run out of vacuum on a gasoline powered car whose throttle is stuck open. This is why, in the runaway SUA cases on the hgihway that were being investigated here, repeated braking did not slow the car down.

On a diesel car, the brakes *should* still work because turbodiesels have no intake vacuum. They use a separate vacuum pump to power the brakes. So for the highway SUA incidents with the Montero, you still need two failure points, as opposed to one on a gasoline car.

I do agree that it will be difficult to stop the car if the driver isn't expecting it... most drivers don't press the brakes hard enough, and riding them to combat SUA can cause the fluid to boil or the pads to overheat, rendering the brakes useless.

I still wonder, in these cases, why the driver could not shift into N, as that is on a separate control module. I recall in one of the more famous SUA cases I've read about (a very old one), the throttle got stuck open due to a faulty cruise control, and the mechanical linkage of the cruise to the shifter prevented the driver from shifting into Neutral.
I think SUA victims, was 2-2.5 secs. late in braking... it is also possible that the sudden surge of power, cause them to panic, checking what the hell is wrong....thus braking late... while the car forward momentum is already in motion, and braking will now take a few meters to stop to a halt...