sitting at lights with foot on the brakes - why

bigjl

Zero_Gravitas wrote: »

When I did my advanced driving course, the advice was that if there is any chance of being rear-ended whilst stationary, use the handbrake and the brake pedal. The logic was that:

(1) Your brake lights are on so people behind can see that you are slowing or stopped.
(2) The handbrake only works on the back wheels - if you are rear-ended and the rear of the car leaves the ground, you will then be pushed forwards effectively unbraked.
(3) If you are hit from behind with your foot on the brake, it is unlikely to come off the brake pedal, as the forward momentum imparted by the collision will tend to keep your foot in place, and in fact is likely to increase the pressure exerted.

In general, the routine should be:
(1) stop with foot on brake.
(2) apply handbrake
(3) take foot off brake when the person behind you has come to a halt and you're confident you're not likely to be hit.

Best Regards,

ZG.

Agree with lots of that.

Except the bit about forward momentum.

When a car is bit from the rear the driver and therefore his foot will be pushed backwards momentarily at the point of impact. The same mechanism that causes whiplash.

Hence why when you go to a line of cars involved in a chain of rear impacts the one at the front tends to be positioned a little differently to the others, maybe off to one side after it has rolled a bit prior to reapplication of the brakes.

GwylimT

I don't drive very often now, but normally I pedal, sometimes I use the hand brake but then I tend to have my food on the brake pedal as well, then all wheels are 'secured' and my brake lights are on.

Ultrasonic

GwylimT wrote: »

I tend to have my food on the brake pedal as well, then all wheels are 'secured' and my brake lights are on.

Could get messy .

bigjl

Ultrasonic wrote: »

I'll be honest and say that I didn't realise that automatics might do this, and I'm confident I'll be far from alone in my ignorance. Given how comparitively rare automatics are in the UK (something like 15%-20% of cars going by a quick Google) there are many drivers who know pretty much nothing about them.

I think that statistic is slightly misleading, don't know where to have found it, as if you consider a large metropolitan area like London the percentage will be much higher.

Most vehicles used for immediate response work with the London based Emergency Services are auto, standard patrol cars like the Astra and Focus are not considered immediate response vehicles even though they do indeed fulfill that role, either is the Patrol Supervisors Zafira as used by the Met. But the area cars and traffic are all auto as are most if not all DPG vehicle except maybe the vans.

LAS and LFB vehicles are automatic and have been for many years as it is considered safer, as you don't need to consider the correct gear to use and both hands are on the wheel more.

But I digress slightly.

I personally think nearer 40% of vehicles in London would be auto.

But I think if you were to look at the vehicles registered over the last three years or so the number would be much higher.

Even the previous Reasonable Prices Car on TG was available with auto.

dazzercx

Mercs tend to have a "hold" function which keeps the brakes applied when you take your foot off in turn keeping the brake lights on. They are released automatically when driving off.

Mine does this and so does the wife's. Maybe other manufacturers with stop start / hill assist e.t.c do the same? maybe it appears more cars are sat with the driver on the foot brake all the time because of these new features?

Just a thought.

Ultrasonic

bigjl wrote: »

I personally think nearer 40% of vehicles in London would be auto.

Most people don't live in London though . But I take your point.

As I said, I just did a quick Google search, with not one particularly obviously reliable figure or I'd have posted a link.

I'm still willing to bet that most (i.e. >50%) of UK drivers have never driven an automatic. But whatever the figure there are still lots of people with very limited knowledge of them.

It's interesting that you think the number of automatics is increasing though. Particularly given they are pretty universally less fuel efficient than manuals and the obsession of the majority of buyers with fuel economy.

marlot

RichardD1970 wrote: »

Maybe the people who have a problem with the brake lights should consult an optician, some people might have a greater sensitivity to bright light and I'm sure that they could get some anti-glare/polarising (not sure which are suitable for night driving) glasses, even if their eyesight is ok.

Not quite that simple. We become more sensitive to glare because the lenses of our eyes thicken and the pupils become smaller. I understand a 55-year old takes eight times longer to recover from glare than a 17-year old.

Negotiator

First world problems?

Ultrasonic wrote: »

What bugs me at lights is people who keep the car in gear, occasionally edging forward a bit. They are pointlessly wasting fuel and wearing out their clutch as far as I can see.

adouglasmhor

TrickyWicky wrote: »

I wouldn't say automatics are rare but there will undoubtedly be those who don't know quite how the gear shift works especially when it comes to the reverse light coming on.

Personally myself, I would never use P while waiting at the lights. If some moron comes along and smashes into you then the park brake in the autobox may get busted and thats a serious repair job. Far better to leave it in N instead but then you still have to apply the foot brake to move it into D or the car will jolt and probably cause more damage to itself like that.

You don't need to use the foot brake to go from N to D or even from P to D on mine. You can flick between N and D but for anything else you need to push the button on the gear stick. The only automatic I had before was an Audi 200 back in the 80s and the setup was different.

skivenov

TrickyWicky wrote: »

Never really understood how an auto works then eh?

If you leave it in D with the hand brake, it's still trying to pull forwards. If another car hits you from behind the car will start pulling forwards and not want to stop. Plus on a hill facing down most auto handbrakes won't hold in D at all.

Although I learnt to drive in a manual, I was told that if you drive an auto, you only use the handbrake for parking and keep your foot on the footbrake at lights etc. Shifting from N to D requires you to hit the footbrake, move the shift and wait for it to move into gear. That can often take longer than a manual gearbox being put into 1st.

Funnily enough, I could probably have quite a long boring conversation with you on exactly how an auto works.

That aside, when I did my first 3 year renewal on my advanced, I did it in an auto. I was trained to hold it on the handbrake for a short stop, and shift neutral on a longer stop. In most auto's, you don't need the brake pedal down or to press the lock button to knock it in N. Pulling away, brake down, put in in D drop the handbrake and creep away letting the handbrake up isn't any harder than pulling away in a manual, and the flash of your brake lights wakes the people behind you up.

If you're sat in D with your foot on the brakes and someone goes in the back of you, your foot is going to come off and the car will set off.