I dare you

When have you ever gotten an invitation like this? "What I want you to do is get that tractor going as fast as you can, then dynamite the brakes and see what happens?"

Actually, I got a similar invitation many years ago, but it involved a loaded tractor trailer on a wet runway to try out antilock braking systems.

I received this most recent speed and brake invitation while on an exclusive press tour to Meritor's truck brake manufacturing plant in Cwmbran (pronounced "Kah-braun") in Torfaen, Wales, United Kingdom. I didn't even bother to RSVP. I headed straight for a rig, climbed aboard and fired up its diesel engine.

The idea was to experience, behind the wheel, the stopping capabilities of commercial vehicles with air disc brakes (ADBs). ADBs have been the standard spec for commercial vehicles throughout Europe for years now.

The vehicles I got to brake test, European heavy trucks (all cabover models, of course), were:

  • A Scania truck and full trailer (which was loaded). In this vehicle combination, known as a Rigid in Europe, the trailer is connected by means of a single axle converter dolly trailer.
  • A 4x2 Volvo tractor and a fully loaded three-axle flatbed semitrailer.
  • A 3-axle Scania tractor with weight added to simulate a loaded trailer.
  • A 4x2 Iveco tractor.

There was a mix of automated and manual transmissions.

True and straight

I must say, the stopping ability of ADBs is powerful and impressive. No matter the vehicle I was in, when I mashed the brake pedal to the floor, it aggressively came to a quick, true and straight, controlled stop, in a considerably shorter stopping distance than a rig outfitted with both antilock and electronic braking systems and drum brakes. I can attest to this because I drove vehicles with both types of braking systems.

The stopping force of the ADBs was such that I figured I would have been catapulted through the windscreen (that's European for windshield) had I not been snuggly seat-belted in.

Watch this video to get a feel for the braking power of ADBs.


Don't hit that cone

To make things even more interesting, our select group North American editors were invited to compete in a Go and Stop competition. This is where you get behind the wheel of a 4x2 Iveco tractor with an automated transmission, put the accelerator to the floor to get the truck going as fast as possible in a straight line, then estimate the necessary distance to stop before striking an orange traffic cone and then brake accordingly.

It has to be a hard brake, no stop and release and stop and release.

We were allowed one practice run.

I am proud to say I won the competition, stopping about 6" from the cone in the fastest time.

Watch this video of the Go and Stop competition from inside a tractor.