The Road Ahead : April May 2008
features STORY BARRY GREEN PHOTOS JIM McEWAN The boss has given you the golden handshake and you're off to spend the kids' inheritance. The caravan is hitched and ahead lays an open road. Final destination? Who knows. You head off, making good progress, your towing rig devouring kilometre after kilometre as it lopes along the highway. Too easy. Then, without warning, the caravan breaks into an uncontrollable sway. Your life flashes before you. And then, it can be all over. Just ask acting Sergeant Andrew King and his colleagues at the Sunshine Coast Police District Accident Investigation Squad. All-too-often they get to see the dire consequences of what is called 'side sway', where violent oscillations of the caravan cause the driver to lose control instantly, without warning. In investigating one such fatal smash, the squad sought the expert opinion of a retired mechanical engineer. According to the specialist, it takes a combination of adverse conditions to induce side sway. The list includes: air pressure from a passing truck or bus, bumps or grooves in the road surface, cross winds, downforce on the tow ball that is too low or too high (sometimes caused by incorrect storage of heavy items) and the location of the caravan's axles being too close to the centre. In his report, the specialist said the affect of side sway could be reduced by "manual over-ride application of the caravan brake." y j knife option." Sgt King said, from his experience, the choice of tow vehicle had much to do with side sway. "Speed is not usually the issue," Sgt King said. "(Instead) many smashes involving caravans could be put down to an inadequate vehicle being used to do the towing. "I mean a Commodore or Falcon, or something smaller. "The power-to-weight ratio is just not there." Sgt King said a volatile mix of heavy transport and holiday traffic meant caravanners needed to be vigilant when travelling roads such as the Bruce Highway, on the Sunshine Coast. "Near the deer sanctuary (at Forest Glen), there's a cross wind phenomenon that can cause plenty of problems," he said. Caravanning Queensland technical consultant Gerry Newton has some potentially life-saving advice for anyone considering buying a caravan. "You need to build up experience, take it slowly at first and get used to the van before attempting a higher speed," Mr Newton said. "Pay important attention to tyre pressures on both the van and tow vehicle, and the load distribution, which should be 60/40, front to rear. "Be aware of your braking distance and allow a realistic distance for overtaking and being overtaken. "You need a good set of mirrors (on the tow vehicle) and need to drive at a comfortable speed. "By that, I mean at a speed at which you are in control. You can't have the caravan controlling you." "However, if (instead) the tow vehicle brake is applied, a jack-knife immediately happens," he warned. "Panic by the driver often favours the jack- Trouble IN TOW CARAVAN TIPS For further advice, contact the RACQ Technical Advisory service on 3666 9148 or (if calling from outside Brisbane) 1800 623 456. You can also access technical advice, including fact sheets, via the RACQ website, racq.com. 28 APR/MAY 08 ABOVE: Safe towing requires practice and the right rig.
February March 2008
June July 2008