Central Tire Inflation (CTI) was developed during World War 2 as a means to improve mobility of military vehicles in difficult terrain. Moving forward two or three decades and CTI came under the scrutiny of North American Forest interests giving rise to modern day commercial CTI Systems. TractionAir was developed in New Zealand in the 90’s with input from local and Australian logging operators. Our objective was to design an operator focussed, user-friendly system and from its release it quickly found favour in the region.
Without TractionAir, life is a compromise for tyres. They get inflated to around 100 psi because at some stage the truck or trailer will be loaded with its maximum payload. The CTI concept is to match tyre pressures with the load and the speed of the vehicle. TractionAir enables you to adjust the pressure to suit both without leaving the cab. Steel belted Radial Truck tyres are designed to flex, maintain correct tyre sidewall deflection ratios, and you gain huge traction advantages (reducing wheel slip) whilst reducing vibration. It is this vibration reduction that produces the greatest cost savings.
The correct pressure setting for an 11R 22.5 Tyre at 100kph will be when the Tyre’s Sidewall is deflected by 12% of its unloaded height. At 10kph, that sidewall deflection can be increased to 30%, which will double the footprint, and halve ground pressure.