Braking and Turning

[Astraist]

I am aware that many of you probably consider steering and hard braking to be seperate actions, but if a driver is faced with a mid-corner emergency which requires him to stop, I would not overrule braking. In fact, with ABS it's quite simple: Kick the brakes, keep the steering wheel still, and roll to a stop. Without ABS, it gets rather problematic: One needs to brake hard, while doing three things:
1. Stop the car quickly, within the limits of skill from the average driver.
2. Maintain steerability -- In layman's terms, avoid understeer by keeping the front tyres rolling.
3. Avoid oversteer.

The third goal is quite easy to achieve: The driver just takes off a bit of steering while braking, and the car almost never reaches any angle to it's back-end. However, one must brake hard, but without locking the front tyres. In one course I have been on, the instruction was to brake only moderatly-hard to begin with (about 70%), getting a good compromize between stopping distances and car control. Thus far it's what I recommend, but do you believe there is another way, possibly easier to perform or more efficient, should the need to brake would arouse mid-corner?

The considered option include: Braking semi-hard to begin with; braking as hard as possible, and than releasing a bit to release the front tyres (which should be better but takes quite some skill), or cadence braking (which is easy to perform but highly inefficient).

The goal is to decide on a course of action that would do the job for the average driver, when faced with an sudden emergency.

Other possibilities are welcome.

[Stephen]

With ABS brake and steer if required,it gets harder if no ABS.
Stephen

[Nanuq]

Good post, but wouldn't entering into a hazard with the correct speed and gear be the prefered option?
The ability to comfortably stop on your own side of the road in the distance you can see to be clear would negate the need to worry about such an event.
In fact the consideration of such an event should be foremost in anyones mind before entering said bend.

If it were the case that an individual were asleep on the entry into a bend, not observing limit points as they should and ultimately going too fast without the steering assistance afforded by ABS under heavy braking, then I would consider how well I had written my will, what my insurance company may say if I couldn't avoid a collision and probably a spot of cadance braking, last ditch efforts rarely work though.

[Mr Cholmondeley-Warner]

I like your style, Northern one

[7db]

Don't forget if you have £10 of grip and you spend £5 on cornering then you only have £8.66 left to spend on braking.

[Martin A]

Hi All

Don't forget if you have £10 of grip and you spend £5 on cornering then you only have £8.66 left to spend on braking.

Which may not save your life, but at least you'll finally understand U turns in economic policy .

Hope this helps

Best regards

Martin A

[Astraist]

As I have said, the problem does not relate to ABS cars. Without ABS, I would not recommend cadence braking, because it might unsettle the car by constant weight transitions. In spite of advanced observations skills, you can be surprised, and the average driver would be even more so surprised. The idea is to develop a technique that is relatively easy to perform well in a surprising emergency situation.

Don't forget if you have £10 of grip and you spend £5 on cornering then you only have £8.66 left to spend on braking.

Keep in mind, however, that modern cars have a very high limit of grip, which are rarely maxed out on the road, even be it wet. Additionally, modern cars have clever suspension systems that can balance out small differences in grip/slip between the different axles. Moreover, by taking off a bit of steering lock while braking, you release some of your budget on lateral adhesion and have even more to brake.

Besides, if something runs in front of you, what else would you do? Decrease your levels of adhesion by placing even more steering movements without decelerating? hit it head on? You need to stop, no matter if your car turns into a whirlpool (which it will not). I have seen and done it, it works!

Without people voting, I will be inclined to continue with the current approach (brake only semi-hard to begin with).

[Octy_Ross]

The ability to comfortably stop on your own side of the road in the distance you can see to be clear would negate the need to worry about such an event.
In fact the consideration of such an event should be foremost in anyones mind before entering said bend.

And what about the cute deer that just appeared out of the hedge 2/3m in front of you?

[ScoobyChris]

And what about the cute deer that just appeared out of the hedge 2/3m in front of you?

http://www.bdfa.co.uk/recipes.php ?

Chris

[Mr Cholmondeley-Warner]

Getting a bit precise aren't we? Surely if it was only 2/3 (or 0.66 recurring) of a metre in front of you, you'd hit it before you noticed it emerging, so hardly something you can plan for. Better to just be fatalistic about deer, and concentrate on the things you do have control of, imho

[7db]

I can't help thinking the natural instinctive reaction is not bad, leading to interference braking
- brake as hard as you can as early as possible
- remember to let go of the brakes to allow the steering to work if you're not in ABS

It's not optimal, but it is easy.

[Nanuq]

The ability to comfortably stop on your own side of the road in the distance you can see to be clear would negate the need to worry about such an event.
In fact the consideration of such an event should be foremost in anyones mind before entering said bend.

And what about the cute deer that just appeared out of the hedge 2/3m in front of you?

Unfortunately the chances of me putting my car into a ditch for a 'cute deer' are slim to none. Whilst I have a healthy respect for most living things (the exception being drunk, uninsured, unlicenced drivers and the remaining scum of the earth, that of course being another topic of discussion for another day) the deer is unfortunately not likely to survive. Having said that, and before I get bounced for the 'what if it were a child' statement, I would not be carrying any speed into or near any place where children are likely to be, were, once existed are likely to exist in the near future.

There is no trade off for speed over safety. I've said it once and I'll say it again; vision is life, speed is death and the unexpected will always happen, plan for it! If you do, excessive braking whilst steering will never come into play.

If you can see through a bend, a nice clear open sweeping bend then vision up, max drive. If you can not see every inch of the road surface then you must be able to stop comfortably on your own side of the road in the distance you can see to be clear. If you are unable to achive that then you are simply travelling way too fast, you are out of control and you are going to have a collision!

[zadocbrown]

Cute they may be but they can do a hell of a lot of damage. Regardless of the moral implications I would rather do what I can to avoid hitting one.

[waremark]

If you can see through a bend, a nice clear open sweeping bend then vision up, max drive. If you can not see every inch of the road surface then you must be able to stop comfortably on your own side of the road in the distance you can see to be clear. If you are unable to achive that then you are simply travelling way too fast, you are out of control and you are going to have a collision!

This reminds me of the only time I can remember making what I would describe as an emergency stop on the road. I was driving round a left hand bend at about 60 mph on a two way country road on which there is generally a decent amount of room to pass oncoming vehicles. There was a heavy coming towards me very much in the middle of the road (there would have been comfortable room to pass if he had been tucked in to the left). I made a full ABS stop and came to a halt well tucked in to the left verge. The heavy coming towards me continued onwards in the middle of the road for a while with its wheels locked up, and luckily came to a halt just before hitting me.

Two lessons learned. I now go round that same bend (which I do often) a little slower, so as to be able to stop in half the distance I can see to be clear a bit more comfortably. And I realised afterwards that instead of sitting still waiting to see if the heavy would hit me, I should have slipped my car into reverse and started moving away from him. I hope I will have the presence of mind to do that if the same thing happens again.

Astraist, since 2003 all new cars sold in the EU have had ABS. This means that most people taking driving instruction will never drive a car without ABS. For cars with ABS, the need is to get drivers to press the brakes hard enough. Without ABS, like DB7, I think I would go for max braking, then reduce pressure slightly when I get lock up.

[jont]

And I realised afterwards that instead of sitting still waiting to see if the heavy would hit me, I should have slipped my car into reverse and started moving away from him. I hope I will have the presence of mind to do that if the same thing happens again.

If you have even more presence of mind, you might temper that decision depending on whether you noticed anyone following you and how far back in case they came round the same LH corner to find someone reversing towards them?