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The recent spell of bad weather has brought travel chaos and disruption along with it for the ride - but operators can do more to ensure their drivers have total control of their vehicle Words: Bob Beech Once again, the recent spell of bad weather has caused chaos and disruption to the country's transport infrastructure, delaying deliveries, leaving people stranded and ultimately costing millions in lost productivity.
Almost as soon as the traffic grinds to a halt, so the accusations of incompetence begin. Why wasn't more done to prevent the chaos — and why didn't the authorities anticipate the problem and have more gritters, snowploughs and labour, etc, available?
Very often, traffic comes to a standstill because of the actions of the least capable road user, be it pedestrian, car or truck driver. More often than not, even if the car driver is the culprit, the public only seems to notice the trucks.
The usual comparison with the way Scandinavian countries and other Nordic regions cope with winter weather are not really valid — after all, their roads are generally far less congested than ours. If a truck grinds to a halt in northern Sweden, it doesn't quickly result in traffic chaos because there are fewer road users outside of the big cities. Also the very cold weather lasts far longer, and truck operators and governments are able to invest in the correct equipment to deal with these conditions, safe in the knowledge that they will get full use from their investment.
Meanwhile, problems persist whenever we have anything more than a light dusting of snow, which begs the question: is the transport industry doing everything it can to prepare for bad weather? Can anything be done to lessen the effect of winter, or are we right to simply accept that Britain cannot cope?
Truthfully, many operators are not doing enough in many respects to deal with winter. While modern trucks, when properly maintained and prepared, will run without complaint whatever the weather, it appears that many drivers do not know how to get the best from their trucks when there is snow on the ground. Adding to the problem is the fact that some operators optimise the specification of their vehicles for use in good weather, which has the reverse effect in bad weather.
We encountered an example of this last winter when a recovery driver informed us that he had to tow in a number of petrol tankers fitted with automated gearboxes after their clutches had failed in extremely cold weather. Because of petroleum regulations, the trucks were not fitted with night heaters, so to keep warm while stopping in freezing conditions, drivers were forced to keep their engines running. However, in the operator's quest for improved fuel economy, the trucks had been specified with automated shutdown of the engines after a few minutes of idling. Consequently, drivers resorted to leaving the gear selector in 'drive' to override the anti-idling, causing the clutch plate to bind and eventually fail. The incremental fuel saving throughout the course of the year was soon outweighed by the cost of recovery, repair and loss of use.
Best use of technology In the past few weeks, we have seen countless examples of drivers struggling to get traction with 6x2 tractor units fitted with automated gearboxes and weight transfer systems. While in some instances a combination of worn tyres and poor road conditions were to blame, in many situations the driver was simply not making the best use of the available technology. For drivers who have to cope with poor ground conditions on a daily basis, such as timber and agricultural hauliers, much of this becomes second nature. But many others who spend nearly all of their time on tarmac, have clearly never been shown, or have forgotten, how to deal with these situations.
Take automated gearboxes for an example. Rightly so, the focus of any training given on how to get the best from this technology has centred on fuel saving, with the emphasis on using the fully automatic mode in the majority of situations, and relying on the electronics to make most of the decisions. In fact, some manufacturers offer a simplified fleet specification, whereby the driver cannot select the manual mode. While this is designed to prevent abuse, especially from less-experienced drivers, it can cause problems as soon as traction is lost. Being unable to select the manual mode makes some trucks incredibly difficult to drive in bad weather. The problems arise when the wheels begin to spin, the engine revs increase and the gearbox starts to change up. The driver keeps the throttle planted and the ASR/traction control (if fitted) then kicks in and kills the revs. The gearbox makes a rapid down-change and then the whole process starts all over again.
If, however, the driver was able to select the manual mode, the correct procedure would be as follows.
Driving on snow The best option is to select the manual mode, disable the traction control via the switch on the dash and engage the diff-lock (if fitted). Then, as with a manual gearbox, raise the starting gear to about third gear and feed the power in as gently as possible. Once the truck starts moving at a reasonable pace on flat ground, gently change up a gear or two, keeping the revs to a minimum Never try to engage or disengage the diff-lock when the wheels are spinning because it may damage the cliff. Sometimes it's best to leave it engaged on very slippery surfaces unless turning sharply where it might affect steering.
It is likely that few drivers have ever been taught the correct way to use this technology and, in some circumstances, it is unclear if trainers know the correct procedure.
If the truck is a 6x2 and is not fully laden, there will rarely be enough weight on the drive axle to get a decent grip on an icy surface. The obvious thing to do in this situation, before trying to move, is to use the weight transfer system and increase the load on the drive-axle. Again, there seems to be a lot of confusion about this. Most trucks either use separate switches or a combined switch to operate the lifting and load transfer functions. Scania has a useful dash display that shows the weight imposed on either axle, with the load on the drive axle increasing accordingly when the centre axle is dumped.
Too often we see drivers with both centre-lift and tag-axle tractors who don't understand that there is little point in trying to lift the axle when fully laden. Legislation permits up to a 30% increase in drive-axle loading, either for a limited time and/or up to a set speed. It's good practice to use these systems in ordinary weather conditions to reduce tyre scrub and steering effort when turning sharply, especially with an automated gearbox. The added tyre scrub increases resistance and makes it more difficult to sense the clutch-biting point, drivers then floor the throttle and the truck begins to lurch and jump about.
Surely professional driving is about making the best use of the vehicle technology at the driver's disposal. It costs millions to develop these systems, but the most vital part of the process is imparting this knowledge to the end user — the driver. It seems that the Driver CPC is a missed opportunity to enhance the combined skills of the industry; there is a world of difference between being compliant and competent. •