ARTICLE: Safe Driving in the Rains

[Vivek Jayan]

Originally Posted by mail4ajo

It could have been answered earlier. Whenever I use the wiper in rain, there is some haze on my windscreen. It irritates when there is oncoming traffic. It appears only when I use the wipers. There is not fogging otherwise. Is it the wipers or do I need to clean the windscreen?

Try wetting the windscreen and wiping it clean with a newspaper. Apart from your wipers being old, it could also be some sort of waxy residue. Many so called "glass cleaners" today are useful for household items only. Even though some claim that they can be useful for car windscreens, they leave behind a thin residue which is supposed to help repel dust. But what this does is mar your visibility when something swipes through- like a wiper. I learnt this the hard way. Another idea to increase the lifespan of your wipers is to keep them raised when the car is parked for long hours, especially if under the sun. The rubber blade might tend to stick to the windscreen during prolonged exposure to high temperatures and might leave marks on the glass when used after a long time and cause uneven wear.

[greenhorn]

I was driving through some water and rains, when I noticed that the feel of the brakes had become very different. Instead of the progressive usual action, they did nothing at first, and at one point, bit in hard (the way you feel when you use disc brakes for the first time)
any idea why ?

[Vivek Jayan]

Originally Posted by greenhorn

I was driving through some water and rains, when I noticed that the feel of the brakes had become very different. Instead of the progressive usual action, they did nothing at first, and at one point, bit in hard (the way you feel when you use disc brakes for the first time)
any idea why ?

I'm guessing that water must have entered in between the rotors and brake pads and is causing the loss of friction while braking. The water is then squeezed out as you hold on to the brakes, after which they suddenly engage. It is generally advised that the brakes be pumped a couple of times to squeeze out excess water from the pads and/or rotors after driving the vehicle through wet conditions. Maybe you can also direct water at high pressure to the brake pads or its casting and possibly remove any dirt or grime that has accumulated there over time.
Again, I'm just guessing here.

[honeybee]

Originally Posted by Vivek Jayan

Try wetting the windscreen and wiping it clean with a newspaper. Apart from your wipers being old, it could also be some sort of waxy residue.

This residue could also be from the wipers. Wiping with a newspaper (the regular one, not the glossy one) should help keep it clean.

Originally Posted by greenhorn

I was driving through some water and rains, when I noticed that the feel of the brakes had become very different. Instead of the progressive usual action, they did nothing at first, and at one point, bit in hard (the way you feel when you use disc brakes for the first time)
any idea why ?

Originally Posted by Vivek Jayan

I'm guessing that water must have entered in between the rotors and brake pads and is causing the loss of friction while braking. The water is then squeezed out as you hold on to the brakes, after which they suddenly engage. It is generally advised that the brakes be pumped a couple of times to squeeze out excess water from the pads and/or rotors after driving the vehicle through wet conditions.

Your guess is bang on, it must be the water. While driving through rains should not cause a loss of braking, driving through water (where your wheels are partly submerged) surely renders the brakes ineffective. Slowing down to manageable speeds in waterlogged sections and once you are out, pumping the brakes a few times helps restore the braking power.

[mooza]

I had my first (rather chilling !), experience of aquaplaning a few months ago, while driving back in my Xylo from Udaipur to Bangalore, on the Belgaum - Chitradurga stretch on NH4 (I had a 2 day break in Mumbai).

I was driving on a straight, level and smooth stretch of the highway. It was raining heavily, and I could see sheets of water on the road. I gradually reduced my speeds to 70 to 75 kmph, and was maintaining this speed for about fifteen minutes or so, and then all of a sudden it happened. The symptoms were as follows:

- I noticed a sudden loss of feel / connect with the road, manifesting as a complete reduction of NVH on the steering (steering wheel vibrations associated with road roughness vanished all of a sudden). I also realised that my car was not responding to the micro steering inputs that one usually gives while driving on the highway. There was an eerie smoothness of the car gliding forward without any control. I say eerie because when I briefly turned around, I saw all the 3 generations of my folks blissfully enjoying their post lunch nap, the cabin totally quiet, with my 2 ton beast gracefully slipping ahead without any control whatsoever.

- Thanks to TBHP inputs, the thought "AQUAPLANING!" hit my mind immediately. I gently eased off on the throttle, did not move the steering much, luckily there were no obstacles, and I started feeling the road once again at around 50 kmph.

We stopped for the rain to subside, and resumed the journey after a fuel and tea break !

[Vivek Jayan]

Originally Posted by mooza

I had my first (rather chilling !), experience of aquaplaning a few months ago, while driving back in my Xylo from Udaipur to Bangalore, on the Belgaum - Chitradurga stretch on NH4 (I had a 2 day break in Mumbai).

Thank God you escaped that without incident! What do you think was the reason for the hydroplaning? Were your tires nearing the end of their lives? Especially the rear ones?

[Thad E Ginathom]

So many people claim to have aquaplaned!

mooza, you most certainly did aquaplane!

What do you think was the reason for the hydroplaning?

You need enough water on the road surface, and enough speed. You cannot aquaplane on a road surface that is simply wet (hence many of the incorrect claims): you need solid water. You can only skid on a wet surface.

Solid water gets between the tires and the road, and then you might as well be on ice.

I'm sure mooza will agree... Once is enough! We were both lucky to be on a straight stretch of road, although, in my case the car swerved slightly to the left. As I had a vehicle on either side of me, and speeds were more like 80MPH (UK motorway) It was a nasty moment.

And all my passenger said was, "did you mean to swerve then?" As a non-technically-minded non-driver, there wasn't a way for me to explain. Probably better she never knew!

In a flash storm, sometimes you just can't slow down soon enough.

[SamirD]

Originally Posted by mooza

I had my first (rather chilling !), experience of aquaplaning a few months ago, while driving back in my Xylo from Udaipur to Bangalore, on the Belgaum - Chitradurga stretch on NH4 (I had a 2 day break in Mumbai).

I was driving on a straight, level and smooth stretch of the highway. It was raining heavily, and I could see sheets of water on the road. I gradually reduced my speeds to 70 to 75 kmph, and was maintaining this speed for about fifteen minutes or so, and then all of a sudden it happened. The symptoms were as follows:

- I noticed a sudden loss of feel / connect with the road, manifesting as a complete reduction of NVH on the steering (steering wheel vibrations associated with road roughness vanished all of a sudden). I also realised that my car was not responding to the micro steering inputs that one usually gives while driving on the highway. There was an eerie smoothness of the car gliding forward without any control. I say eerie because when I briefly turned around, I saw all the 3 generations of my folks blissfully enjoying their post lunch nap, the cabin totally quiet, with my 2 ton beast gracefully slipping ahead without any control whatsoever.

- Thanks to TBHP inputs, the thought "AQUAPLANING!" hit my mind immediately. I gently eased off on the throttle, did not move the steering much, luckily there were no obstacles, and I started feeling the road once again at around 50 kmph.

We stopped for the rain to subside, and resumed the journey after a fuel and tea break !

Whew! You were definitely lucky! After seeing how crazy the driving is on the highways, good idea to stop and let the rain subside.

One trick I use when I see a water ponding on the road where I might hydroplane (aquaplane) is to lift off the accelerator and slow down somewhat before hitting the patch of water. In front wheel drive cars, I'll slightly accelerate leaving the water. If you look far enough ahead, you may even be able to use the brakes to slow down, but be sure to let off of them well before the patch of water.

Originally Posted by Vivek Jayan

What do you think was the reason for the hydroplaning? Were your tires nearing the end of their lives? Especially the rear ones?

Tire tread depth is only one part of the picture. Tread design has a lot to do with it too. I'm sure the tires are designed more for the rugged driving necessary in India versus highway cruising and high-speed water expulsion like here in the US. But if any of the tires were worn, it would be best to be the front ones. If the rears are hydroplaning, that would result in an oversteer situation at high speed--something most drivers in the world can't get out of safely. Better to understeer like the driver experienced.

[Prowler]

Originally Posted by Thad E Ginathom

So many people claim to have aquaplaned!

You need enough water on the road surface, and enough speed. You cannot aquaplane on a road surface that is simply wet (hence many of the incorrect claims): you need solid water. You can only skid on a wet surface.

Solid water gets between the tires and the road, and then you might as well be on ice.

It is very hard to do Aquaplaning with SUVs as it depends on the weight and the surface that comes in contact with road/water. It is quite easy to do that with 2 wheelers and small cars. I did that in my motorcycle days with not-so-disastrous results. Some times when you hit a large body of stagnant water, you might lose control - albeit briefly for a few seconds. But that is not due to Aquaplaning. Your front wheel momentarily rides up leaving you with little 'purchase' on the surface.

[voodoochild]

Couple of weeks ago, I was on a regular weekend motorcycle ride to Lavasa (ghat roads outside Pune). The road surface there is absolutely impeccable. However, there was a slight drizzle. Now there's an ST bus that goes up and down the Lavasa ghats every day. The blighted thing had left a steady, unbroken trail of oil all the way. As we know, oil shows up in rainbow colours when the road is wet. I avoided the oil trail throughout, but at one hairpin (I was at walking pace, no more!) I managed to cut across the trail just when I throttled out of the apex, resulting in a slow-motion lowside.

However, on a three-day ride through torrential downpours late in the monsoon, I had no issues cornering on ghat roads! On much older tyres than the ones I have now. Completely uneventful ride.

Food for thought: The first few rains haven't enough time to wash off oil and debris from tarmac. Also, oil tends to form a uniform layer above the water (oil floats on water, Physics-101). Would this make it harder for a tyre to break the surface and make contact with the ground? Thus increasing chances of hydroplaning in the first rains?
Just something I thought about while straightening my bent footrest that weekend

Originally Posted by Prowler

It is quite easy to do that with 2 wheelers and small cars. I did that in my motorcycle days with not-so-disastrous results.

Wow, I would say you were unbelievably lucky to have "not-so-disastrous" results!

Cheers,
Rahul

[Thad E Ginathom]

Originally Posted by Prowler

It is very hard to do Aquaplaning with SUVs as it depends on the weight and the surface that comes in contact with road/water.

As I said, mostly aquaplaning is actually skidding. However, when it happens it can happen to any vehicle: you just need sufficient speed and sufficient water.