Emergency Stop

[IVORTHE DRIVER]

Hi guys,

Seeing as how the aim of the emergency stop is to avoid hitting something what idiot is teaching someone not to hit the pedal too hard!!

ABS can help the vehicle stop quicker by preventing skidding and that is a fact regardless of road conditions.

I also feel that pupils should be actively encouraged to experience the sensation of ABS assisted braking so that they realise what the brake pedal feels like, I have demonstrated this to my wife just in case but sadly I have not yet managed to convince her to try it for herself!

Ivor

[TripleS]

Hi guys,

Seeing as how the aim of the emergency stop is to avoid hitting something what idiot is teaching someone not to hit the pedal too hard!!

ABS can help the vehicle stop quicker by preventing skidding and that is a fact regardless of road conditions.

I also feel that pupils should be actively encouraged to experience the sensation of ABS assisted braking so that they realise what the brake pedal feels like, I have demonstrated this to my wife just in case but sadly I have not yet managed to convince her to try it for herself!
Ivor

I don't know how feasible this is, but I would like future developments in ABS to get rid of the pulsing/vibration that is felt at the pedal when ABS activates. This would be a better subject for attention than some of the other crap that the designers are putting into cars.

It might be that some drivers - especially those of a more sensitive disposition - take the vibrating pedal to be a sign that something is wrong with the braking system, and they may react by reducing the pedal pressure, which then renders the ABS useless.

Best wishes all,
Dave.

[morsing]

ABS can help the vehicle stop quicker by preventing skidding and that is a fact regardless of road conditions.

Yes and no. ABS stops the car quicker than if you just skid, it does not stop the car quicker than applying the perfect brake pressure by foot, ABS will in fact take longer to stop the car than the perfect pressure will.

To stop the car quickest, you need to apply the amount pressure to the point just before ABS kicks in, as ABS actually works by semi-skidding and if ABS activates it is because you're skidding (slightly) and it will fluctuate between slight skidding and too little braking to get the wheels up to speed again.

ABS was never introduced to reduce braking distances, it was introduced to allow simultaneous braking and steering.

[jont]

I don't know how feasible this is, but I would like future developments in ABS to get rid of the pulsing/vibration that is felt at the pedal when ABS activates. This would be a better subject for attention than some of the other crap that the designers are putting into cars.

It might be that some drivers - especially those of a more sensitive disposition - take the vibrating pedal to be a sign that something is wrong with the braking system, and they may react by reducing the pedal pressure, which then renders the ABS useless.

Hence one of the latest technologies which is emergency brake assist. I think it detects you suddenly applying lots of brake, and then if you suddenly back off (possibly because the ABS has activated), it keeps brake pressure applied. I don't know the details as I've never come across the system in anger so to speak.

[TripleS]

I don't know how feasible this is, but I would like future developments in ABS to get rid of the pulsing/vibration that is felt at the pedal when ABS activates. This would be a better subject for attention than some of the other crap that the designers are putting into cars.

It might be that some drivers - especially those of a more sensitive disposition - take the vibrating pedal to be a sign that something is wrong with the braking system, and they may react by reducing the pedal pressure, which then renders the ABS useless.

Hence one of the latest technologies which is emergency brake assist. I think it detects you suddenly applying lots of brake, and then if you suddenly back off (possibly because the ABS has activated), it keeps brake pressure applied. I don't know the details as I've never come across the system in anger so to speak.

OK, but is that the reason for introducing EBA? I thought I had heard of cases where cars have been rear ended due to a following driver being caught out by the unexpected hard braking. I can see that EBA might be of help in some situations, but if it causes other problems elsewhere, the overall benefit could be questionable. It might be quite difficult to get an EBA system nicely tuned so that it provides useful help, without creating problems due to emergency stops that weren't needed in the first place.

Cue some interesting new forms of insurance wrangle?

Best wishes all,
Dave.

[fungus]

My Fiesta has EBA. My previous experience of it was a few years ago when I test drove a Renault Clio. My recollection was that it felt as if the brake pedal was being taken from me. Although I encourage learners to brake firmly enough to activate the ABS during emergency stop exercises, I have never had any comment other than about the vibration of the brake pedal, of which they are warned.

[drivingschoolnewbury]

"Brake then clutch".

If you try and do both at the same time then there is a danger that you do "clutch then brake" as some of my pupils do. As soon as they do that I can feel the coasting effect and the car takes longer to stop.

I have to agree with some other drivers in that I too am not convinced abouth the engine braking and it may indeed try to keep the car moving at the natural speed for whatever gear you're in and so take longer to stop.

Anyone know the correct proceedure after you stop?

When I took my part 3 to become an ADI I had to teach the emergency stop. Securing the car was "handbrake and then neutral". Even though I passed the examiner said it should have been handbrake and gear 1. The reason he gave was that if there is a big lorry behind who can't stop in time you have the option of pulling forward, if you have the space of course.

However one of my pupils was told by a senior examiner it should be "handbrake and neutral"

What does everyone else think?

[IVORTHE DRIVER]

Hi,

I think in a real emergency stop situation you would be very hard pressed to hit both pedals at the same time because your clutch foot has further to travel (from the floor and up instead of just to one side) so in reality unless you are pre-planning your emergency stop as in a test situation it will always be brake then clutch, but as someone has already said "in the heat of the moment".

Ivor

[ROG]

When I took my part 3 to become an ADI I had to teach the emergency stop. Securing the car was "handbrake and then neutral". Even though I passed the examiner said it should have been handbrake and gear 1. The reason he gave was that if there is a big lorry behind who can't stop in time you have the option of pulling forward, if you have the space of course.

However one of my pupils was told by a senior examiner it should be "handbrake and neutral"

What does everyone else think?

You would need a lot of forward space to reduce any impact.

There is also the argument that being in neutral and just releasing the handbrake would allow much of the impact force to be absorbed by the truck freely pushing it forwards ....... but i'll let the techno folks on here go more into that ......

[crr003]

Anyone know the correct proceedure after you stop?

When I took my part 3 to become an ADI I had to teach the emergency stop. Securing the car was "handbrake and then neutral". Even though I passed the examiner said it should have been handbrake and gear 1. The reason he gave was that if there is a big lorry behind who can't stop in time you have the option of pulling forward, if you have the space of course.

However one of my pupils was told by a senior examiner it should be "handbrake and neutral"

What does everyone else think?

Driving the essential skills says "Unless you're moving off again straight away, put the parking brake on and the gear lever into neutral." implying no need even for the handbrake?!

One driving school I have read says handbrake-neutral and a full blindspot check before moving off.

[Gareth]

Driving the essential skills says "Unless you're moving off again straight away, put the parking brake on and the gear lever into neutral." implying no need even for the handbrake?!

I'd be (mildly/vaguely) interested in your interpretation of the difference between parking brake and handbrake.

[crr003]

Driving the essential skills says "Unless you're moving off again straight away, put the parking brake on and the gear lever into neutral." implying no need even for the handbrake?!

I'd be (mildly/vaguely) interested in your interpretation of the difference between parking brake and handbrake.

Synonymous. Some "parking brakes" are activated by foot, so I suppose D-tes, is covering all eventualities.

Although with a foot activated brake I'd be even less inclined to be doing the hand/footbrake/neutral/both blind spot check before moving off again. Depends on the road and how much is going on I suppose.

[drivingschoolnewbury]

You would need a lot of forward space to reduce any impact.

There is also the argument that being in neutral and just releasing the handbrake would allow much of the impact force to be absorbed by the truck freely pushing it forwards ....... but i'll let the techno folks on here go more into that ......

If you didn't have the space to pull forward to reduce the impact then surely being in neutral with the handbrake off would cause you to be propelled into whatever is in front of you. Maybe a cyclist lying on the road or a jackknifed lorry that you have just emergency stopped for. Not convinced that handbrake off would reduce the forces of the impact. My instinct would be to keep my foot hard on the footbrake (much stronger than the handbrake) and my head pressed hard against the head restaint to reduce whiplash. There would still be a massive impact from behind and your car would still be propelled forward, but at least your car would add some resistance so hopefully won't be hurtled too far forward into other dangers as well.

[Marriott]

Break first clutch after, if you apply the clutch at the same time you have less control of the car.
With the clutch up the gears are still engaged and will help with slowing down the car.
ABS enables you to steer while breaking as your wheels don't lock up, so if you have to break hard then you can still try and steer away from an accident but ABS slightly increases your stopping distance.

[turnerburner666]

Break first clutch after, if you apply the clutch at the same time you have less control of the car.
With the clutch up the gears are still engaged and will help with slowing down the car.
ABS enables you to steer while breaking as your wheels don't lock up, so if you have to break hard then you can still try and steer away from an accident but ABS slightly increases your stopping distance.

I disagree with the above comment. The engine has momentum at whatever revs it is turning. Under breaking the discs will have to work harder to stop the momentum of the car AND the engine if the clutch is left depressed until the last minute...and has been stated earlier, if you get the timing wrong you could face the engine management system raising the revs to prevent a stall, or a stall of the engine...either way, this gives you less control as they are opposing forces.

Break efficiency in most cars these days is such that both pedals can be pressed together.

This is obviously just my opinion and if anyone has any scientific objection on something i have maybe overlooked then i am all ears!