GOOD MOTORING
Total control
H. Kishie Singh 
Using cruise control, which many car companies offer these days, may actually be detrimental given the dismal condition of Indian roads

A lot of cars these days are coming with a fitment referred to as ‘cruise control’. What is it and how does it benefit the driver? As the name suggests, it controls the cruising ability of the car. If you have a long, smooth road ahead for 50 km or more, cruise control is a very practical and handy fitment on the car.

Here is how it works. You accelerate up to the maximum speed limit, say 90 kmph and press the cruise control button. The car will then cruise at 90 kmph without any pressure on the accelerator pedal, even if you are driving on the hills. As soon as your foot touches the brake pedal, the cruise control de-activates and the car is under your control. It no longer has an electronic mind of its own. This is a great fatigue buster because all you have to do is steer the car.

It is purely an American invention where the highways are dedicated exclusively to motorised vehicles. Not only do these super highways have a maximum speed limit, there is a minimum speed limit. Which means no slow coaches are allowed. Two-wheelers, less than 250 cc, may be restricted from using this highway. The highways have guard rails on either side, wide shoulders with gravel traps and a wide centre median. This makes sure that in case of a mishap, a car won’t enter the on-coming traffic’s lane. There are no potholes, no roadworks every couple of kilometres, no cows, dogs, women with firewood on their heads or men with ‘lotas’ looking for a bush to answer nature’s call.

We simply do not have the roads for cruise control because of the need to apply brakes frequently

Cruise control won’t work under these conditions, where every couple of minutes you have to apply brakes. Actually, using cruise control on Indian roads may be detrimental. We simply do not have the roads that the cruise control was designed for. It is rocket science technology and we are barely out of the bullock-cart stage. There is a downside to cruise control. It is a fair weather friend, literally. You cannot, or should not, use it when it is raining and the roads are wet. During a heavy monsoon downpour, the water does not drain off fast enough off the roads. Here again our roads are to blame. So, water stays on the roads, besides there is dust and oil on the road which makes the road surface slick. Water accumulates in front of the tyres faster than the weight of the car can push it out of the way.

The water pressure can cause your car to rise up and slide on top of a thin layer of water between the tyres and the road. The car is then riding on water. It has lost contact with the earth. The steering has been rendered completely useless. It is like driving on ice. This effect is referred to as hydroplanning or aquaplanning. To avoid this extremely dangerous scenario, reduce speed. Do not brake sharply. As the car slows down, the weight of the car will settle the car down. The car is in touch with earth once again. This will not happen if the car is on cruise control. If you are on a highway in heavy rain, follow in the tracks left by the car ahead of you. The water has been cleared off the tarmac. Chances of hydro-planning are minimal.

Tyre manufacturers are aware of the dangers of hydro-planning. In the last few years, the tread has been designed to clear the water in front of the tyres to prevent hydro-planning. Water enters the cuts in the tyre, referred to as sipes and they allow the water to drain away from the tyre, thus allowing contact with the tarmac. There are uni-directional tyres which give improved wet weather performance. Be very alert while installing these. I have seen uni-directional tyres mounted wrongly. You have rendered the tyre useless and made the car lame! Some manufacturers have an aqua-tread. These are designed for wet roads. These are also good on dry tarmac. There are also all-weather tyres or all-terrain tyres. Whatever they are called, the primary purpose of a tyre is to keep the car on the road, through mud, slush, snow and possibly ice. There is one situation the tyres can’t handle; hydro-planning! The only antidote to hydro-planning is to reduce speed.

Car manufactures are also concerned about hydro-planning. Toyota has a model, the Sienna Ltd XLE. The car does not allow you to set cruise control if the wipers are on. And if you are on cruise control and switch on the wipers, the cruise control is automatically de-activated. That’s Toyota! Almost every car you buy today has some warnings listed on the sun-visor. My suggestion to manufacturers and local dealers is to have a sticker. "Do not use cruise control on wet roads". This could be posted along with the other warnings on the sun-visor. It would be a service to customers that could save a life. Happy Motoring.