This articles follows on from my previous one, which was based mainly on The Rules of Braking, from the Police Road Craft Book. Today I am dealing with more in depth thinking and analysis of various braking situations.
Braking is one of the moments that can make a vehicle very unstable, if not given enough thought, it could mean the difference between life and death.
You have got to take the weight of the vehicle and its contents into account. The way the undulations and bends with the different cambers, plus the weather, all have an effect. Oh! Yes, speed as well.
If you chug along at 20 mph many of the above have much less effect on your vehicle when you come to brake. It is still worth reading though.
Higher speeds can affect the stability of your vehicle if used in the wrong place. If for an example you have undulations as apposed to hills, you will find that as you go over the rises in the road your suspension becomes light and to touch your brakes harshly at this moment could cause a momentary lock up.
You have to wait until the vehicle is over the rise and settled back on its haunches / suspension, then your tires will be in good contact with the road, with much better grip, so you can get a much better braking effect. You will be able to steer as well.
Your initial touching of the brake pedal will need some thought, not hard onto the brake pedal, that alone could induce a skid for a moment.
As you come over the rise in the road, sorry, preferably prior to negotiating the rise, you must think about the distance to the main hazard you are dealing with.
If the above undulations are on the approach to a major hazard, try to look well forward and get as much speed off before having to deal with those undulations in the manner above.
Braking can be done over a long distance, depending on your speed. Over that distance the surface can change several times, especially just after a fall of heavy rain. In other words, if the surface varies then your braking and touch of the brake pedal must vary to accommodate the prevailing conditions.
An example of going over different road conditions and dealing with them after being progressive. Brake firmly in a straight line, come off the brake pressure as you go over a slight rise in the road, letting the vehicle settle on its suspension on the other side, now back to firmer braking.
Next going through a puddle, come off everything and hold the steering wheel, very firmly. When out of the water on a damp but good surface feel the pressure but not really firm until you have got a lot more speed off, or when coming onto the Non-slip surface, usually light tan in colour, which you will see on the approach of many major junctions, brake firmly on this tan surface even in the wet, to be safer before the forthcoming hazard.
Do not leave all your braking until you are actually on that non-slip surface, you may not have enough time on your side.
Late braking for Traffic Lights:-
Getting caught out by those lights that change against you when you were just saying to yourself, “ I am going.” “ Oh no.”
A green light is the most difficult to approach, when you first see it green take a flexible gear, that is one that will help you use the engine to go, or slow when the
engine compression will be helping your brakes to restrain the vehicle.
If they should change against you, come onto the brake firmly, realising that as your nose dives, the back end of your vehicle lifts up, as well as you, your passengers, and every item in your vehicle.
Just before, and I mean just before, you come to a stop, take off some pressure on that brake, NO, I did not say come off the brake, then immediately back hard on the brake. You will then come to a controlled stop.
It will help a great deal to practice, just give yourself a spot to brake to, some where quiet even off road, maybe an empty car park. Always use your mirrors before and while doing this manouver even off road. To begin with, try braking firmly to a stop, no particular spot needs to be used on this occasion, do this without locking up the road wheels, it will take time.
What has happened, while you were first braking, with everything being lifted and thrown forward, by coming off the pressure on the brake for just a moment immediately prior to you coming to a stop, things have settled down somewhat. So that your last piece of firm braking has not such a dramatic affect.
Believe me it works, it always make me think of a Tom and Gerry cartoon moment, they are always over exaggerated. It needs safe practice. This will give you more confidence in braking generally.
While the above is going on do not depress the clutch, it's very tempting to do so. If you press the clutch you loose the help you get from the engine compression, as long as the engine is connected to the road wheels you have that help. Press the clutch and you loose it.
Depress the clutch at the last second of the first piece of braking for the late changing traffic light as above. Here is an extreme example of what depressing the clutch at the wrong time would cause, going down a steep hill in a low enough gear restraining the vehicle, should you press the clutch at this time the vehicle would run away gaining speed rapidly.
A.B.S and Cadence Braking:-
While on the subject of braking I must include something about A.B.S. Which is an electronic / mechanical action on your brakes. It comes in when you have left it too late, and are pressing the brake pedal for all it's worth. Saying to yourself, “Please stop!'
A.B.S. Took the place of ' Cadence Braking ' Cadence is done purely by the trained driver with there foot going hard on, hard off, on, off, on, off, on, off, and so on. This is much slower than A.B.S. but serves the same purpose for split seconds.
While on the brake you may be sliding or possibly loosing a little speed if at all. When off the brake you could have a rolling action with the road wheels
and while this is happening you can get some steering! Not much, but hopefully at least some.
Do not rely on ABS, the adverts in the past when ABS first appeared were too misleading, making you think you could drive fast in the wet and tired, when surprised by a truck pulling out, you could steer round it and drive on, so cool, not in the real world though. Even in an recent brochure advert for a well known car this again is suggested.
Please get that out of your mind. In reality, the only thing that it might do, is allow you to steer just enough so that instead of hitting a pedestrian, you may just clip them, hopefully with no injury or death. Yes only that amount of steering at the most.
Cadence braking used in the real world:-
I had an experience outside Buckingham Palace right by the Victoria Monument, known in London as the ' Wedding Cake ' just because it looks like one.
I was on an emergency call and it was raining, I was going across the front of the Palace Gates with the Wedding Cake to my right, with the intention of going up Constitution Hill towards Hyde Park Corner, to that emergency call.
It was dusk, so I had my Blue Lights going and the Horns going, which was all there was in those days. As I came towards the Wedding Cake a tourist driving from my right, failing to treat the Wedding Cake as the center of a roundabout, drifted pointing at the palace, right across my path, towards the Palace gates.
Being truly honest this was the only time I attempt Cadence Braking, A.B.S. had not been developed enough at this time, during training at Hendon on my Advance Driving Course I was taught it and practiced. To my surprise it clicked in on, off, on, off and so on, as above.
It gave me just enough time to go round the back of the oblivious motorist, to this day I am sure he never new a thing about the Police Car even being there. We steadied up and were away up Constitution Hill. Phew!Let's hope you never have to use Cadence or A.B.S.
TAKE GOOD CARE OUT THERE, NO ONE CAN DO IT FOR YOU.
DAN MOONIE
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