GORV - Digital Magazine Issue #7 | Page 13

| RV FEATURE MYTH 3 For optimum stability, all caravans need about 10% tow ball mass. REALITY Desirable tow ball mass is more an issue of where mass is along that caravan. That 10% is easily remembered and generally adequate. A short centre-heavy caravan, however, needs far less than does a long end-heavy caravan. Camper trailers prove this. Most are a mere four metres, yet some weigh close to two tonnes. Almost all are ultra-stable; however, their recommended tow ball mass varies from 3% to an extraordinary 20%. MYTH 4 It is fine to have end weight (like toolboxes and spare wheels) as long as the front end is heavier than the back. REALITY This is commonly believed. It is a very dangerous myth as it results in oil tanker-like handling. Some are normally ultra-stable but if a sufficient side force does cause one to yaw (snake), that end mass that kept it seemingly stable may now not be correctable. If that occurs, jack-knifing is virtually inevitable. MYTH 5 People carry on about the various alleged effects of weight. However, that’s just their opinion. The real world is quite different — all that’s needed is everyday common sense. REALITY This is the ongoing bane of many an internet forum. People are entitled to form their own ‘opinions’ but not their own engineering facts. The effect of weight and mass is totally basic physics understood and accepted since 1687. gorv.com.au 13