Rod Chapman•22 Sept 2014

FEATURE

Feature: DECA rollover course

In an effort to address rollover statistics, DECA's Rollover Prevention and Stability Program is taking truck drivers to the very brink – and beyond…

It seems like barely a day goes by in Australia without the mainstream press highlighting another heavy vehicle accident. A high proportion of those accidents are truck rollovers and, as we saw with the Cootes Transport tragedy, when the load is a flammable liquid, the results can be catastrophic.

Driver Education Centre of Australia, or DECA, has set out to address these statistics with its Rollover Prevention and Stability Program. Warren Smith, Business Manager of DECA's Shepparton campus in Victoria, co-wrote and developed the course, which was introduced in 2010. A truck driver for 23 years and involved in the industry for far longer than that, Warren says rollovers are common for good reason.

"Professional drivers spend all their lives trying not to tip their truck over," he says.

"We all know there's a line in the sand at which point a truck will tip, but where is that line and how close do we come to it on a daily basis? Many drivers estimate they have a safety margin in corners of around 10-15km/h, but the reality is it's often as low as 4-5km/h."

The course is utilised by operators looking to train their drivers, reduce their risk of an accident and protect their major assets – namely the driver, the truck and the trailer. With obvious benefit for transporters of fuel and gas, momentum has built to the point where companies like BP and BOC are putting all their tanker drivers through the course, flying them in from all over the country to attend.

Courses are run twice a week with four students per class. The stability course is a full day – although it can be combined with an advanced driving course that extends it to two.

In simple terms, the course highlights the physics involved in driving a truck with either a trailer or a tanker, showing professional drivers ways in which they can reduce their risk of a rollover. However, it's the practical component that makes the course unique.

The trailers used – either a curtain-sider or a tanker – are each fitted with outrigger arms with a wheel on the end. Towed behind a prime mover, the outriggers allow students to see for themselves how easy it is to take the truck to rollover point – in complete safely.

The course is only available at DECA's Shepparton campus for good reason, says Warren – he says it's the largest concrete skidpan in the southern hemisphere.

"You can't really do it on bitumen race tracks because of the weights involved, so it really does require a large area like the one we have here," he says.

trucksales.com.au recently had the opportunity to attend the course along with four drivers from WA-based Marsue Transport. Marsue Transport is the sole WA distributer for BOC International gases; in fact it was BOC that approached DECA some years ago to explore the possibility of developing a rollover course.

"Some of the executives from the UK came to us and said, 'We want something like this worldwide – can you do it for us?'," says Warren.

"That's how it began. We had the trailers fitted up locally, we wrote the program, and here we are."

The four Marsue Transport drivers – Nathan, Dave, Glen and Rob – have experience in heavy- and multi-combination rigs ranging from a few years to 20 years, and find themselves driving a range of trucks all over WA.

Our instructor, Dave Arthur, begins with the basics…

"This course has been put together for truck drivers, by truck drivers – not by some shiny-arse who's never sat in a truck," he says.

With 33 years of truck driving behind him there's little doubting his word – especially as he still drives interstate a few days a week, mainly running hanging meat from Warragul, Vic, up to Sydney.

After a quick intro from each of the drivers, we have a quick refresher on the road rules, defensive driving and hazard perception, before looking at DECA's system of vehicle control.

The system of control is a logical sequence with which a driver can approach any hazard, the term 'hazard' including a bend, roundabout or intersection. It's all about braking before the corner and entering it in the right gear, before maintaining speed to the apex and then accelerating smoothly to the exit.

The penalty for changing gears through the corner is amplified for tankers because the liquid will shift as a result, destabilising the truck. "Once that weight starts pushing you, you're no longer in control," says Dave.

"You need the truck sorted and settled before you enter that corner; it just makes the truck more stable."

Liquid sloshing forward during a mid-corner down-change also elevates the risk of a jack-knife, while of course the liquid moves to the outside of the tanker through a bend, thereby shifting the tanker's centre of gravity.

Cement trucks require extra care. While their rigid format negates certain risks, the anti-clockwise rotation of their agitators means they're more prone to tipping through a left-hand bend – think halfway through a roundabout, when the truck changes direction to exit. Having said that, extra care is required on any corner – by their very nature agitators have an ever-changing centre of gravity.

Dave also spends some time on trucks with modern automated manual transmissions, suggesting it's far better to negotiate roundabouts or intersections in manual mode to retain full control.

The tone is chatty but the seriousness of the topic is never far away. At one point we look at exactly who is impacted by any rollover fatality – it's a list that goes on and on. The classroom is an open forum, with drivers recognised as the professionals they are and free share their own experiences and ask plenty of questions.

FORCE OF NATURE

After a break, Warren pops in to take us through the dynamics at play in a moving truck. While a truck travelling down a straight road only has a few forces at work – namely the power of the truck to keep it moving versus wind resistance and rolling resistance – in a corner centrifugal force comes into play, and that's when the problems can start.

"The science is complex but you have to know that every interaction you have with a vehicle has consequences," he says.

"Show the trailer who's boss – pull it around the corner."

As for baffles or compartments in tankers, they can't change the laws of physics.

"It doesn't really matter how the liquid is contained," says Warren. "You've still got the same amount of volume moving around in there."

A number of eye-opening video clips show just how punishing those laws of physics can be. In slow motion, the rear of a flat-top trailer is virtually sliding down the road on its side before the prime mover even begins to shift, the torsional forces extending through the length of the trailer eventually flicking the tug over and smacking it back down into the road, rather like cracking a whip.

It's a common theme – by the time the truckie knows something's amiss it's already too late.

"Don't ever kid yourself that you can feel a rollover coming – it's the biggest myth out there," says Warren.

Modern trucks with their advanced suspension might give us a silky-smooth ride but they also isolate the driver from the forces at work, giving very little warning of potentially dangerous conditions.

"We've lost the feel – it's taken away what the truck's doing," says Dave.

Modern trucks also have more power, increased cab comfort, better brakes and more automation, but the threat of rollovers doesn't go away. Even modern safety aids like electronic stability control, electronic brake systems and roll stability systems aren't foolproof, as Dave sums up.

"They can help in avoiding a rollover but they don't replace you blokes," he says.

"These systems are not there to be relied on or depended upon; they're purely there as a backup if you have a lapse of concentration."

The dynamic forces are one thing, but the physics of tipping points is also crucial. While a prime mover might have a lateral tipping point of 70 degrees – that is, it can be tilted on its side to 70 degrees before it rolls over – the tipping point for the loaded trailer of a log truck might only be 15 degrees. Factor in the camber of the road and that figure might drop back to 10 degrees – even less if the trailer's tyres are on the doughy side. That's right, incorrect tyre pressures also play a role.

"Now you can understand why there are often only four to five kays an hour of speed in it before you roll over," warns Dave.

Different trailer designs have different centres of gravity and then that centre of gravity will shift as multi-drop drivers make deliveries. Dropping one trailer to hitch up another can also catch out the unwary.

After a quick 'mechanical appreciation' class – another worthwhile session where we inspect the inner workings of components like a Roadranger gearbox, differentials, and brake boosters – it's time to put all the morning's theory into practice on the skidpan. It's crunch time – or hopefully not…

TIPPING POINT

The practical session on the skidpan certainly helps the morning's theory gel and gives an insight into how little input and speed is required to roll a truck.

Our test mule, an Isuzu Gigamax hooked up to a tanker carrying 20,000 litre of water, has a travelling weight of around 34 tonnes. With those massive outriggers in place there's little chance of anything going drastically wrong, but I'd be lying if I said my pulse isn't racing as I grip the wheel.

We each cycle through two exercises: first a giant loop at 30-35km/h, then a J-shaped course at 40-45km/h. We do each one twice – once without the rig's Knorr-Bremse electronic brake system and roll stability system, and then again with the systems activated.

With NSW in the process of moving to mandatory EBS trailer brakes this technology is set to spread – but that doesn't mean there isn't a need for drivers to be trained in how it works and its shortcomings.

"We get drivers who say to us, 'Oh, I've got EBS on my truck and I hate it', then they do this course and they go away with a whole different outlook because they then understand why it's doing certain things – and that is it's identifying certain faults in their driving style that could have potentially been a disaster," says Warren.

So what's it like to take a loaded tanker to tipping point? Scarily unremarkable. Unremarkable in that you just can't feel the tanker starting to go, and scary because, well – because you just can't feel that tanker starting to go.

"There was no inkling whatsoever," says Dave from Marsue who, like most who've completed this course, can probably think back to past occasions when a rollover was actually a lot closer than they thought.

The second exercise gives me a double wake-up call when the truck starts to roll and jack-knife at the same time – it may have only been a gentle grass embankment rushing up to meet me, but the experience showed in an instant how with a bit of weight things can go very wrong, very quickly.

On the flipside, completing the exercises with the Knorr-Bremse EBS/RSS systems activated shows just how effective they can be. This two-stage system initially sees some braking applied independently to certain wheels to restore control, then also taking away throttle input if required. It's not foolproof, as Dave says, but in the vast majority of situations it gets things back on track, heading off a nasty incident.

THE BOTTOM LINE

While some authorities may lead us to believe that better roads, safer vehicles and better enforcement is the way forward to lower accident rates, Warren says that's ignoring a vital piece of the road safety puzzle.

"While there's a human responsible for controlling a vehicle, we need to consider that element," he says.

"We need to have better licencing and we need to have better training. Yes, we're in the business of training, but we're also very passionate about road safety and the well-being of the road transport industry."

Truck rollovers are occurring with alarming regularity, often with tragic consequences. DECA's rollover course isn't cheap but the price pales into insignificance next to the virtually limitless costs potentially incurred by a rollover and its aftermath. It simply makes good sense, and that's why major operators like BOC and BP have incorporated this course into their safety and compliance frameworks.

Besides, you can't really put a value on the knowledge this course imparts – knowledge drivers should carry with them for the rest of their careers.

Dave sums it up as only a truckie can. "You've got wives and families to go home to. They expect you home, so make sure you get home."

For more information on DECA's Rollover Prevention and Stability Program call 1300 365 400 or visit www.deca.com.au

Feature: DECA rollover course

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