low power overtaking
Discussion
I would be interested to hear peoples view when overtaking on a road that can comfortably take 3 abreast.
A potential overtaker may see this as a good reason to overtake despite oncomming traffic and so clear the slower traffic sooner, however if someone in the other lane decides the same then we are in danger of a collsion.
So do you alter your overtaking habits in this situation, or do stick to the same procedure as you would where only two car abreat is possible?
A potential overtaker may see this as a good reason to overtake despite oncomming traffic and so clear the slower traffic sooner, however if someone in the other lane decides the same then we are in danger of a collsion.
So do you alter your overtaking habits in this situation, or do stick to the same procedure as you would where only two car abreat is possible?
jeremyc said:
As well as all of the valid reasons regarding observation and timing of the commitment point made already, there is another benefit in moving to the right before accelerating in terms of vehicle dynamics.
The 'lunge' technique means that you will be accelerating whilst turning, with all of the bad weight transferance this inccurs. If something should go wrong during the manoeuvre your car will not be ideally balanced to be able to take the necessary avoidance action. Worse still, if there is limited grip during your 'lunge' then you are potentially going to have all kinds of unwanted sideways action (from the back, front or both).
Accelerate in a straight line and everything will nbe much better balanced, much safer, and you'll be in a much better position to get out of trouble if you decide to abort the overtake.
How very true
My Saab 9000 2.3t would carry straight on when pressed to pass rapidly on a wet road, terminal torque steer would see to any precision manouvers often becoming a little too close.
My MX5 now with nearly 200bhp at the rear wheels lights them up quite merrily at 40mph in 3rd gear. Any sudden weight shift will have you passing McNumpty mid drift, not a wise idea. I think the same can be said for any high powered RWD car without TC.
The gap technique would cure most of those handling ills
>> Edited by cptsideways on Friday 5th November 20:57
gopher said:
I would be interested to hear peoples view when overtaking on a road that can comfortably take 3 abreast.
A potential overtaker may see this as a good reason to overtake despite oncomming traffic and so clear the slower traffic sooner, however if someone in the other lane decides the same then we are in danger of a collsion.
So do you alter your overtaking habits in this situation, or do stick to the same procedure as you would where only two car abreat is possible?
A303 Ilminster bypas (now modified thank god) The classic suicide road if there ever was one. I have personaly witnessed two mulitiple head ons on that stretch in my regular works treks down there. (I used to overtake on it only on my side of the road btw)
It may well have been clear for one to go & you may have been looking 400 yards+ up the road but if an oncoming driver thought the same, you might not know about it, as it'd be too late
. Pigeon said:
safespeed said:
cptsideways said:
I know what you mean, but the big gap is the key, it gives you time so your not rushed into an instant yes or no decision & you always have somewhere to go should it not pan out. Or your passed so quickly its not a problem.
I find the Elastic band technique (comes from driving underpowered cars) teaches you better decision making especially with the big gap. Using this technique with a small gap & reduced visibility is probably lethal I quite agree.
I still don't see the bit in your post that many here agree is critically important. Exactly where are you when you commit to the overtake?
Answering as one who uses this technique and finds this thread a most helpful source of useful thoughts... There are two "points of commitment" - the physical one, where there is no longer room to brake and remain behind the car instead of overtaking, and the mental one, when you make the decision to go for it or not. In my case the mental point would occur on the right hand side of the road able to see clearly past the car in front, accelerating, and before passing the physical point. (Though of course I may make a negative decision at any earlier point if I see something coming.)
Just to complicate things even further, I often find I do a bizarre inversion of the "elastic band" technique!
The typical case is when you are approach a slow moving vehicle with a fairly large speed differential. If you are to continue at your current speed then the "point of commitment" happens relatively early, ie while you are still a bit too far behind the vehicle to be entirely happy about your observation.
So what I find myself doing in this situation is actually to brake as I am positioning for the overtake, perhaps combining this with a down-change. This means that the point of commitment moves much closer to the car in front, so I can get a later view of the road ahead before I have to make the commitment to the overtake.
To be honest, this is something I've tended to do simply because it "feels right", it's only now I've sat down to analyse this logically that I've realised why this makes sense. At first glance the concept of braking whilst catching a car you intend to overtake on a straight empty road sounds wrong, but once we think about the effect it has on the "point of no return" I think it makes perfect sense.
It's strange that twenty years ago I'd be building the speed up prior to committing to the overtake, yet now I often find I'm doing the opposite!
>> Edited by BlackStuff on Friday 5th November 21:06
BlackStuff said:
So what I find myself doing in this situation is actually to brake as I am positioning for the overtake, perhaps combining this with a down-change. This means that the point of commitment moves much closer to the car in front, so I can get a later view of the road ahead before I have to make the commitment to the overtake.
This is critically important at stages in block overtakes. At one stage yesterday I overtook about ten well spaced vehicles in a block, but I didn't sit on the right with my foot on the floor. Instead I treated them as about 10 individual overtakes, slowing to a decision point and then going again.
If anyone's having problems with the idea or the feel of choosing to overtake after you have pulled out onto the other side of the road, you should try comparing the experience of overtaking the second in line with the first. Chances are you find the second easier, but the first can be as easy as that.
cptsideways said:
The bit I disagree with in roadcraft is the pull out onto the offside after reducing the gap. Without accelerating. Quite often mr Numpty will brake as you go to overtake or "appear to" this will leave you in the lurch 9/10 times & is VERY dangerous.
Blimey. That hasn't happened to me in living memory. What are you doing wrong??? <grin>
cptsideways said:
Also reducing the gap is directly proprtionate to lack of visibilty at a time precisely when you need it (to initiate the pull out to the offside). The IAM method in my book is dangerous practice as a routine. It has its benefits at times but is poor practice unless you have a very fast car that can see round things, eg a Cayenne Turbo!
Ah, now we're into the next layer of complexity - position for vision and planning to overtake. You certainly have to be prepared to move left and right and forwards and backwards to earn your view.
cptsideways said:
One other point I have noticed many drivers will react poorly if they see you are about to pass. Often they look in their mirrors for the first time in miles, wander, accelerate, block you anything but carry on as normal. As a rule by leaving the gap you leave the decision making up to you not to mr Numpty. I will only normally indicate to those behind not to those in front.
Often there's no need to indicate at all. It depends if anyone will benefit from the signal.
safespeed said:
cptsideways said:
The bit I disagree with in roadcraft is the pull out onto the offside after reducing the gap. Without accelerating. Quite often mr Numpty will brake as you go to overtake or "appear to" this will leave you in the lurch 9/10 times & is VERY dangerous.
Blimey. That hasn't happened to me in living memory. What are you doing wrong??? <grin>
Never!!!!????, down are way where we have all the retired people its a good percentage of overtakes result in some sort of adverse reaction. Today I followed at a distance an obviously vision impared driver (easy to spot they drive like its foggy) at 30mph down a road that is taken by most traffic at 50+ mph. Sure enough they braked as I passed. Or is it only me that checks the reaction as I pass?
Where do you live? must be somewhere with proper drivers not everyone doing a blanket 40mph like Surrey, Sussex or South Dorset
I gaurantee I can see it happen at least once a week, even if I'm following someone else who's overtaking.
safespeed said:
cptsideways said:
Also reducing the gap is directly proprtionate to lack of visibilty at a time precisely when you need it (to initiate the pull out to the offside). The IAM method in my book is dangerous practice as a routine. It has its benefits at times but is poor practice unless you have a very fast car that can see round things, eg a Cayenne Turbo!
Ah, now we're into the next layer of complexity - position for vision and planning to overtake. You certainly have to be prepared to move left and right and forwards and backwards to earn your view.
Agreed the whole road is yours if you know how to use it
safespeed said:
cptsideways said:
One other point I have noticed many drivers will react poorly if they see you are about to pass. Often they look in their mirrors for the first time in miles, wander, accelerate, block you anything but carry on as normal. As a rule by leaving the gap you leave the decision making up to you not to mr Numpty. I will only normally indicate to those behind not to those in front.
Often there's no need to indicate at all. It depends if anyone will benefit from the signal.
Agreed
>> Edited by cptsideways on Friday 5th November 22:53
safespeed said:
safespeed said:
leosayer said:
Thanks Paul, I was just going to ask what the correct method was.
Now, what about overtaking method in a high-powered car??
This is my normal technique in a high powered vehicle.
1) Follow at about 0.75 to 1 seconds. Select the best gear.
2) When clear pull out to the right for a good look.
3) If clear, commit to the overtake and accelerate briskly.
4) Continue to accelerate past and move back smoothly.
5) If there's oncoming traffic I count the interval between fully returning to the left and the oncomer passing. This is a judgement calibration check. Anything under 2 seconds is dodgy.
The following distance is more variable in a high powered vehicle. I might move up to 0.5 seconds immediately before I anticipate a good opportunity, but would drop back quite a bit during periods of "no go".
Paul
Why do you need to be closer to the vehicle in front in a high powered vehicle rather than a low powered vehicle?
Just curious....
I think there are three basic reasons, the first is becasue you can - there are more options for moving around behind when you're developing your view and planning your overtake. The second is to give a little more time to build up speed before the point of commitment in the low powered vehicle. The third is to enable snappier overtaking in the high powered vehicle - an impossible option in the low powered vehicle.
I think the bottom line is that the power of the vehicle influences the size of the region within which the closer following position exists. With more power available the region is longer in both directions.
It's very difficult to define the close following position with precision. I've never seen anyone dare to do so in print.
Not realy sure what you mean by point 1.
Point 2 - Where is the vehicle when the speed is being built up? Still behind the target car or on the right?
Point 3 - Snappier overtaking? Surely a high powered vehicle has adequate acceleration available anyway?
When I drive my own (high powered) vehicle or my wife's (low powered) vehicle my overtaking technique is exactly the same.
I do worry about the wisdom in trying to define different types of overtakes for different vehicles. You may have said this yourself, but I do think that the drivers of low powered vehicles may just have to accept the fact that maybe they shouldn't be looking to overtake unless it is obviously 'on'.
ca092003 said:
I do worry about the wisdom in trying to define different types of overtakes for different vehicles. You may have said this yourself, but I do think that the drivers of low powered vehicles may just have to accept the fact that maybe they shouldn't be looking to overtake unless it is obviously 'on'.
I think there is definitely a distinction in technique, and this is why:
One of the objectives in a "good" overtake is to pass the other vehicle with a safe speed differential - say somewhere between 15 and 25 mph faster. With a high performance car this differential can be obtained very quickly, so you can begin the manoeuvre from close behind and still attain the ideal speed differential. This opens up more options because your point of commitment is relatively late - which is good.
With a low performance car you should still be looking for the same sort of speed differential, but you can't accelerate as fast so you have to start accelerating earlier. This means that your point of commitment needs to be earlier, and at a higher speed, hence the need for a longer initial gap.
I only agree when I'm on the bike, 'cos it goes from numpty-speed to warp-9 in not a lot of time.
In the car, almost any car that is, you need sooooo much space compared to the bike. Eg, your fastish 4-wheeler will take over twice as long to get past as a mediochre 600cc bike, and need 4 times the width. And run the risk of spinning wheels.
My panzer needs winding up a bit, and if it means the occasional "mission abort", then so be it. But I'd sooner fly past than crawl past.
In the car, almost any car that is, you need sooooo much space compared to the bike. Eg, your fastish 4-wheeler will take over twice as long to get past as a mediochre 600cc bike, and need 4 times the width. And run the risk of spinning wheels.
My panzer needs winding up a bit, and if it means the occasional "mission abort", then so be it. But I'd sooner fly past than crawl past.
cptsideways said:
The bit I disagree with in roadcraft is the pull out onto the offside after reducing the gap. Without accelerating. Quite often mr Numpty will brake as you go to overtake or "appear to" this will leave you in the lurch 9/10 times & is VERY dangerous.
Blimey. That hasn't happened to me in living memory. What are you doing wrong??? <grin>
Never!!!!????, down are way where we have all the retired people its a good percentage of overtakes result in some sort of adverse reaction. Today I followed at a distance an obviously vision impared driver (easy to spot they drive like its foggy) at 30mph down a road that is taken by most traffic at 50+ mph. Sure enough they braked as I passed. Or is it only me that checks the reaction as I pass?
Where do you live? must be somewhere with proper drivers not everyone doing a blanket 40mph like Surrey, Sussex or South Dorset
North Scotland. There are still opportuinties for proper driving up here.
But I travel around quite a bit these days - I did 400 miles yesterday - and I REALLY don't get that problem. It might have to do with taking an offside position early when overtaking.
safespeed said:
ca092003 said:
safespeed said:
The following distance is more variable in a high powered vehicle. I might move up to 0.5 seconds immediately before I anticipate a good opportunity, but would drop back quite a bit during periods of "no go".
Paul
Why do you need to be closer to the vehicle in front in a high powered vehicle rather than a low powered vehicle?
Just curious....
I think there are three basic reasons, the first is becasue you can - there are more options for moving around behind when you're developing your view and planning your overtake. The second is to give a little more time to build up speed before the point of commitment in the low powered vehicle. The third is to enable snappier overtaking in the high powered vehicle - an impossible option in the low powered vehicle.
I think the bottom line is that the power of the vehicle influences the size of the region within which the closer following position exists. With more power available the region is longer in both directions.
It's very difficult to define the close following position with precision. I've never seen anyone dare to do so in print.
ca092003 said:
Not realy sure what you mean by point 1.
With more power you can move up and drop back more quickly as you're developing your view. You've probably got more engine braking too.
ca092003 said:
Point 2 - Where is the vehicle when the speed is being built up? Still behind the target car or on the right?
The basic method involves building up speed AFTER you have pulled out. One should not be absolutely inflexible, but then again one must always avoid committing from behind. (But you can "cheat" at the end of right hand bends - you get the full offside view while you're still on the left.)
ca092003 said:
Point 3 - Snappier overtaking? Surely a high powered vehicle has adequate acceleration available anyway?
Ah yes, but if you can find a safe way of starting from closer you'll be past sooner. It's about finding the optimal point.
ca092003 said:
When I drive my own (high powered) vehicle or my wife's (low powered) vehicle my overtaking technique is exactly the same.
Then I reckon you must be missing out on getting the most out of the high powered vehicle.
ca092003 said:
I do worry about the wisdom in trying to define different types of overtakes for different vehicles. You may have said this yourself, but I do think that the drivers of low powered vehicles may just have to accept the fact that maybe they shouldn't be looking to overtake unless it is obviously 'on'.
It's about getting the most out of it isn't it? We're looking for the best technique given all the circumstances. The power of your vehicle is one of the circumstances.
Certainly there are times when you can't overtake in a low powered vehicle, where you could if you had more grunt.
>> Edited by safespeed on Saturday 6th November 01:31
safespeed said:
This is critically important at stages in block overtakes. At one stage yesterday I overtook about ten well spaced vehicles in a block, but I didn't sit on the right with my foot on the floor. Instead I treated them as about 10 individual overtakes, slowing to a decision point and then going again.
I did a RideDrive yesterday and did exactly the same. I passed 4-5 well spaced vehicles, not foot to the floor but sort of cruising past, then slowed, while still 'out', before committing to the last. I decided the last overtake was still on so carried on and pulled back with plenty of space left to the oncoming vehicle. Discussing it with the coach afterwards, I felt I had hesitated and perhaps should have pressed on with the last overtake without slowing but he said the same as you - it is perfectly good practice to stay out while making up your mind whether the overtake is 'on' or not.
Interesting to see you say the same thing so soon after I had the actual experience.
tvrslag said:Sorry, small cars are less kind to the environment, they emit less plant food (carbon dioxide) per mile and so fail to boost crop yields and tree growth, so lentil munchers have less to munch and less to hug
...small cars are...kinder to the environment...
tvrslag said:if someone volunteers, please ask for two and give me one, never possible to have too many cars with too much power. Ta muchly
Give me a big car with lots of torque any day.
ca092003 said:
I do worry about the wisdom in trying to define different types of overtakes for different vehicles...
One point to bear in mind is the expectation of other road users. In a powerful car you can very safely overtake a line of tailgaters and pull in well before any oncoming vehicle. BUT the lead car approaching you in the opposite direction may well instinctively assess the situation as though they were in their car in your situation and panic. Panic can cause serious grief. Not frightening numpties is a key issue for overtaking in powerful cars.
>> Edited by turbobloke on Saturday 6th November 13:50
Observer said:
This is critically important at stages in block overtakes. At one stage yesterday I overtook about ten well spaced vehicles in a block, but I didn't sit on the right with my foot on the floor. Instead I treated them as about 10 individual overtakes, slowing to a decision point and then going again.
I did a RideDrive yesterday and did exactly the same. I passed 4-5 well spaced vehicles, not foot to the floor but sort of cruising past, then slowed, while still 'out', before committing to the last. I decided the last overtake was still on so carried on and pulled back with plenty of space left to the oncoming vehicle. Discussing it with the coach afterwards, I felt I had hesitated and perhaps should have pressed on with the last overtake without slowing but he said the same as you - it is perfectly good practice to stay out while making up your mind whether the overtake is 'on' or not.
Interesting to see you say the same thing so soon after I had the actual experience.
Brilliant.
Of course the critical underlying factor is that rushed overtaking decisions are bloody dangerous. Take a little bit longer - be absolutely certain that it's safe - and then GLF. That's the way.
-DeaDLocK- said:
Hmmm...
My technique is a bit different.
When I'm approaching a known zone of opportunity while behind a slow moving vehicle I always hang back at about 5 car lengths and begin to accelerate just before the corner that exposes the overtaking road ends.
So in other words I accelerate before I know whether or not I can make the overtake.
If it's clear, I carry on and by the time I'm on the other side of the road there is a large speed differential and consequently the amount of time I spend on the wrong side of the road is severely reduced.
But I always anticipate moderate braking in the event the road is not clear and I always time the acceleration and judge the initial distance between cars so that in the event the road is not clear, I have ample space to brake.
Is this wrong?
No it certainly is not wrong in my opinion. That is basically the system I have been using for very many years, and if I may say so I think you have explained it very well. Obviously the technique works best on roads you know well, but the principle can be applied elsewhere with suitable care.
Best wishes all,
Dave.
cliffe_mafia said:
In a lot of people's minds Speed Kills = No Speeding = No Overtaking.
This is how the government sees it too - there are plenty of roads where overtaking has been prevented with islands, etc.
Also how many people have been flashed by drivers on the other side of the road after a perfectly safe around the limit overtake?
Occasionally I get flashed by a driver coming the other way as I'm completing an overtake. In some cases it happens when there is a great deal of spare time and space available, but still they do it. I usually wave back to thank them for their greeting.
Best wishes all,
Dave.
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