CSA and brakes: The points are the last thing I'd worry about
August 20, 2012
It's funny that drivers place so much more emphasis on speed and performance over stopping capacity. All the horsepower in the world won't help when you're in too close to the vehicle in front and you need to stop now
In a pinch, brake performance can be the difference between life and death. That's a lesson some learn only the hard way.
That drivers take brake performance so much for granted is, at various times, both a little disconcerting and a testament to the reliability of our brake systems. It's unfortunate that drivers seldom experience their brakes in full-performance mode. If they did, they might develop an appreciation for how much work they do -- and how important proper function is to a successful outcome in a panic stop. Pedal to the metal
Several years ago, at the Bendix test facility in Elyria, Ohio, the company was demonstrating disc brake systems for the trade press. Part of the demonstration included a series of full-application stops from 50 mph with disc- and drum-equipped trucks. As a CDL holder, I was able to drive the test rather than sit in the passenger seat observing.
We started out on the oval part of the track, getting the trucks up to 50 mph, then we turned into the paved infield -- where there was lots of room for a gaffe -- and made a pedal-to-the-metal, full-pressure brake application and held it until the truck stopped.
The disc-brake-equipped trucks stopped straight and true each time, and in progressively shorter distances as the brakes got hot on subsequent runs. The drum-brake equipped trucks shuddered a little in the final few feet of the stop, and stopping distances grew progressively longer as the brakes got hotter.
Aside from the inspiring stopping ability of the disc brakes, the test illustrated how quickly the stopping power of the drum-brakes diminished as the brakes became hotter and began to fade on subsequent test runs. That's not a slight of drum brakes, by the way, but a situation to be expected. It's even more important when considering that all the test trucks had perfectly adjusted and maintained braking systems. That's not always the case in real life.
Which brings us to the point of this story: the frequency with which CVSA picks off trucks with brake problems is something we should all be lying awake at night worrying about.The Calamity Quotient
A story that will appear in the September issue of Heavy Duty Trucking
relates brakes to CSA scores. It seems that CSA has finally got fleets' attention when it comes to brake maintenance. Funny thing, that. A few little points has such an effect on maintenance protocols. If I was a fleet, the CSA points would be the last thing I worried about when it came to my brakes. Getting caught with bad brakes would be a blessing in disguise in some cases.
I'd be most fearful that my brakes might be deemed deficient if I was in a crash. You'd be in a world of hurt if a post-crash inspection of the truck revealed some difficulty that a plaintiff's attorney could translate into, "the truck could have stopped sooner" for the benefit of the jury.
I actually think many drivers are afraid of their brakes because they have never made a full panic stop under controlled conditions like we did at Bendix. They simply wouldn't know what to expect. Yet some drive as if they have all the confidence in the world in their brakes. Those are the drivers you need to watch out for.
At the other end of the spectrum, there are trucks out there I wouldn't want to make a full-on panic stop in. You might not be able to control the truck when it takes off in some unexpected direction. Given the possible variations in friction materials, brake adjustment, application and release timing, and a host of other mechanical factors that could be less than ideal, a full brake application could be a pretty exciting event in some trucks.
But I'll bet there isn't a driver out there -- with good or bad brakes -- who hasn't made a low power complaint about their engine. I wonder how many have ever complained about a truck that just won't stop.
Author: Jim Park | Posted @ Monday, August 20, 2012 10:36 PM