When I come up to people with the subject of emergency braking, they bring up all sorts of wierd things: "Pump", "Squeeze", "Brake and release", "be carefull when braking and perfer steering", "stamp on the brakes", etc...
The thing that surprises me most, as a trainer, is not how confident they are of the solution they suggested, but rather how confident they are in their ability to perform it.
The scene: Me and a trainee, in a car, on a big empty piece of tarmac, with several cones. We drive up to a specific, and not too high a speed, and than I order him to "Brake"! and he goes for it. "How do you think you did?" I ask. "Fine. Went hard for the brakes like you said".
The problem with this trainee, is that he set out to do one thing, and sincerely believes he did it, but actually performed something completly different. It is a sad fact of the life on the road, that people do not brake nearly as hard not as fast as they should.
The direct reason is the uncomfortable load transfer to the front of the car, which occurance people tend to fear when at speed. They believe that, because they travel faster, their braking needs to be more gentle. And, in general, our normal braking skills involve a very gentle application of the pedal.
In a crash-site, you will normally notice evidance of hard braking only a few metres before the crash. This means that the driver tried to get away without nailing the pedal and when he saw it's no good, he started to increase the pressure, not reaching effective deceleration early enough.
When an emergency is concerned, this line of thought is misleading -- when the car is traveling at a high speed, a greater pressure over the brake pedal is required to slow it down effectively, not less pressure! Therefore, good hard braking starts hard and eases up if nessecary afterwards, rather being progressively increased.
What about the danger of skidding, you might ask? Well, most modern cars have good ABS systems, which eliminates this problem. But even without ABS, a car skidding, with all four wheels locked, will stop damn fast. In fact, on good tarmac, many ABS systems (usually of models made before 2004) would stop slightly further away than four locked tires.
Additionally, the fear of "lost of control" during such a skid is completly redundant. Skidding under braking will always occur in a straight line and the car will remain pitched forward. If your tire maintainence is bad, or if the grip of the surface is slightly split (different layers of water on either side of the car or two wheels that dropped over to the gravel or grassy shoulder of the road), the car might "rotate" slightly around it's own axle by a few degrees, but the direction of travel is kept. Even if the car was to spin completly (which it will not) it would keep on going straight while spinning.
http://www.youtube.com/watch?v=SbE01I0CioU
Avoidance braking
I have also heard the claim that steering is prefered over braking. To clear that point up, let me share a small story with you:
Our story begins in a car driven on the highway by a she-driver at a very reasonable speed of 60mph, when suddenly, the driver noticed a box dropped on the road in front, a truck parked on the shoulder of the road and the truck driver going to pick up the fallen merchendise.
Our hero started debating with herself: What to do? Steering to the right would bring her towards the truck and the driver, while steering to the left brings her awfully close to the divider fence. As she lingered in arguments with herself, her car was still rolling ahead towards the obstacle at a high speed. Eventually, she paniced, steered sharply to the left with partial braking, and due to the speed involved, spun twice while hitting the guardrail a few times, thankfully not being seriously hurt.
This story, like many alike, teaches us some important lessons: First, brake (hard) first, and than decide what to do. This slows matters down, so you actually earn more time to respond and you also give time to the obstacle (if it's a pedestrian, animal or upcoming car) to respond. Additionally, you wipe off speed to enable the evasive manouver to be pulled-off effectively, and also in any case, should you hit something.
Second, we learn that steering and than introducing the braking effort, greatly effects car stability, and that it is better to brake and than steer. If you do not have ABS, lift off of the brake when you want to steer. If you shake your head and force yourself you look away and than focus on a visual target in the correct direction, you will manage to escape that way.
Third, we learn that anything short of full-force braking, is not going to yield good results. This is also more logical in traffic: You would prefer being hit from behind when braking hard, over being hit in front by braking to little or from the side by trying to steer out of it. Even if it seems we won't stop in time, we start by braking. A sudden lane-change will only be considered if there really is no room.
Skidding and braking
People are also so well aware of the "fact" that one should not brake when he finds himself skidding. When people tell me that, I immediatly argue back: "What skid"?
There are two types of skids: Understeer and oversteer. During understeer, the wheel feels light and the car seems to turn wider than we expected. In this case, lifting-off of the gas (if pressed) and gently brake a little bit slows down the car and transfers the weight over the front tires, giving them more grip and terminating the slide. So, here braking is effective.
The other type of skid oversteer, is when the back of the car is sliding, resulting in the front turning in "too much". In this case, braking would transfer more weight to the front and will only make the rear grip even less. What should we do than? "Steer into the skid" people shout at me. Right? Wrong!
A good correction of oversteer depends on many factors, and often does not involve countersteering or steering into the skid. Furthermore, such a correction carries a great risk of creating a slide the other way. This slide will always be more powerfull, harder to correct and have a far greater risk of being in an accident.
My point is that correcting sudden oversteer is really hard and requires a lot of training. For the majority of road drivers, the best solution is to brake really hard (as opposite to the partial application of the brakes when most people brake). This will slow down the vehicle significantly, and can either straighten the car back up or stop it while it's still in the direction of intended travel.[/b]
Identify what type of emergency brake your car uses. Handbrakes are found between the passenger and driver seats. Footbrake pedals are found by the driver's feet at the far left of the driver's seat. Pull brake handles are found between the steering wheel and stereo.
2.
Step 2
Practice making an emergency stop. Find a secluded road or parking lot where you won't encounter much traffic. Do not go faster than 20 MPH. For a handbrake, push in the top button and pull up slowly. For footbrakes, you need to pull a release brake and then press on the pedal. For a pull brake, grab the handle, twist it to the left and pull. Apply the emergency brake gently for the first few times, then full force to experience full driving conditions.
3.
Step 3
Identify if the driving situation you're in is an emergency. An emergency exists if your automobile is in motion without a working brake system, or if your normal brakes can't stop your automobile in time before impact with an object.
4.
Step 4
Drive away from traffic. If you can divert your car away from the source of danger even a small amount, you stand a greater chance of avoiding collision or minimizing damage.
5.
Step 5
Activate your car's emergency brake. Stopping the car too quickly may increase the risk of injury, but being too gentle increases your risk of collision.
6.
Step 6
Use emergency signals if an accident happens, or if the original mechanic problem was not fixed. The car's emergency blinkers can be found above or around the steering wheel. Lifting the hood is another signal that a driver needs help.
Wrong, applying your Emergency brake in a situation requiring an emergency stop is wrong: First, it's a weak brake and operates only on the rear wheels. Second, due to that very fact, it can unsettle the balance of the car. Third, it will take your hand off of the wheel.
Second, car brakes rarely fail completly. There is almost always pressure to slow down the car in a sufficient rate.
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