Undertaking scenarios on motorway

Undertaking scenarios on motorway

Author
Discussion

Chris1255

203 posts

112 months

Thursday 3rd December 2015
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rs1952 said:
Chris1255 said:
Personally think we should just admit defeat and allow passing in any lane, seems to work in the US.
We already do, its just that a) we don't encourage it and b) the Highway Code tells you not to.

But there is no "offence of undertaking," and it amuses me that this comes up so often on a motoring forum where, presumably at least, there are more people who understand the rules of the road and motoring law than in the general public.

Can we have another couple of threads now about how having no "road tax" invalidates your insurance, and that it is illegal to tow on a motorway?

smile
Point is that it's not custom and practice regardless of the exact legal position so in reality you get the 'chicane' situation described by someone above. In the US all the lanes seem to keep moving at their own speed and it's all more relaxed. I imagine if you were undertaking and were swiped by a car moving left insurance companies might take a dim view as well.

ging84

8,920 posts

147 months

Thursday 3rd December 2015
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Jarcy said:
Chris1255 said:
ging84 said:
Jarcy said:
In example 1, I would approach the maneuver in two stages.
a) Pull up parallel with old chap, in lane 1 and match his speed (for a short duration).
b) Then increase speed and carry on your way.
This two stage approach demonstrates due care and attention, and I would not see this as an "undertake".
Why do people like this answer?
how does slowing down in the middle of an under take demonstrate due car and attention ? seems like the exact opposite to me.
Agreed, the biggest risk of an undertake would be the vehicle on the right deciding to move to the correct lane and not expecting anyone to be there or not looking in their blind spot. By slowing down you're staying in that danger zone for longer.

Personally think we should just admit defeat and allow passing in any lane, seems to work in the US.
By slowing down to his speed as you arrive at the "undertake", you have time to react if he starts pulling over. A short press of your brake and you'll safely be behind him if he cuts across. If your closing speed differential is (say) 30mph {to get the job done quickly} then what happens when he (inevitably) picks that exact moment to move across? No chance at all to react, safely or otherwise.
I still don't understand
I don't understand why you would ever want to spend any extra time parallel with a car you are undertaking
You make it sound like there are only 2 possibilities, blast past as 90 without ever slowing down, or slow down while you are along side him

Why wouldn't anyone with an ounce of common sense slow down, before they are next to him, then if the other driver does decide to take that moment to do a 2 lane cut, you don't need a short press of the brake pedal to be safely behind him, you are already safely behind him, and can simply pull out and over take normally

Pete317

1,430 posts

223 months

Thursday 3rd December 2015
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ging84 said:
I don't understand why you would ever want to spend any extra time parallel with a car you are undertaking
I don't understand this myself.
Yet people do that all the time when they're overtaking on the motorway - they complain about lorries passing one another at a glacial pace, yet they do it themselves.

ORD

18,120 posts

128 months

Thursday 3rd December 2015
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I think obeying a simple rule of 'Don't hang out in anyone's blind spot' would halve the number of accidents on the motorway. I am amazed how many people just pootle alongside each other (on either side).

I also have a strong suspicion that MLMs are responsible for a lot of accidents.

I have had to use my brakes hard on the motorway on 4 or 5 occasions in recent years. 1 of those occasions was someone moving from L2 to L3 with no indication and no other warning. The rest were all people joining at junctions and moving immediately to L2 at 50mph without checking their mirrors.

For some motorway slip roads (where drivers seem particularly incompetent), I now move to L3 just before the merge point. 2 lanes is the minimum that I want between me and anyone so stupid that they can't bear to be in L1.

The same goes for 'undertaking'. I am astonished that anyone thinks you cannot just continue in L1 if there is some tit hanging out in L3 (or L4 at times) on an empty motorway. The alternative is to turn that 1 car into an effective 3 or 4 lane rolling road block.

Jarcy

1,559 posts

276 months

Thursday 3rd December 2015
quotequote all
ging84 said:
Jarcy said:
Chris1255 said:
ging84 said:
Jarcy said:
In example 1, I would approach the maneuver in two stages.
a) Pull up parallel with old chap, in lane 1 and match his speed (for a short duration).
b) Then increase speed and carry on your way.
This two stage approach demonstrates due care and attention, and I would not see this as an "undertake".
Why do people like this answer?
how does slowing down in the middle of an under take demonstrate due car and attention ? seems like the exact opposite to me.
Agreed, the biggest risk of an undertake would be the vehicle on the right deciding to move to the correct lane and not expecting anyone to be there or not looking in their blind spot. By slowing down you're staying in that danger zone for longer.

Personally think we should just admit defeat and allow passing in any lane, seems to work in the US.
By slowing down to his speed as you arrive at the "undertake", you have time to react if he starts pulling over. A short press of your brake and you'll safely be behind him if he cuts across. If your closing speed differential is (say) 30mph {to get the job done quickly} then what happens when he (inevitably) picks that exact moment to move across? No chance at all to react, safely or otherwise.
I still don't understand
I don't understand why you would ever want to spend any extra time parallel with a car you are undertaking
You make it sound like there are only 2 possibilities, blast past as 90 without ever slowing down, or slow down while you are along side him

Why wouldn't anyone with an ounce of common sense slow down, before they are next to him, then if the other driver does decide to take that moment to do a 2 lane cut, you don't need a short press of the brake pedal to be safely behind him, you are already safely behind him, and can simply pull out and over take normally
We're agreed that you should slow down to perform this "undertake", rather than blast past.
My initial post was a suggestion as to how to get past within the rules of the road, as neither of the two separate maneuvers a) and b) are in themselves an undertake. It's only combining them into one maneuver that an undertake occurs. Separated by time, we then have two maneuvers. That 'short duration' of time is spent whilst parallel so not in the other guy's blind spot, although one must still take due care in case he does something silly.
But yes, in practice I ensure that this short duration of time approaches zero. i.e. just match the other guy's speed as I pass.
(Or perhaps I'd just sit behind him with full beam on, and lean on my horn until he moved over wink )

ORD

18,120 posts

128 months

Thursday 3rd December 2015
quotequote all
What are you on about? What's this speed matching thing got to do with anything? It's just a dangerous and pointless thing to do.

BertBert

19,072 posts

212 months

Thursday 3rd December 2015
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Of more import is ensuring you have your escape route available ie the hardshoulder to your left.
Bert

Pete317

1,430 posts

223 months

Friday 4th December 2015
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BertBert said:
Of more import is ensuring you have your escape route available ie the hardshoulder to your left.
Bert
At least you have an escape route. Something you generally don't have when you're overtaking in L3, which makes it even more important that you don't dawdle alongside the vehicle which you're passing.

ukaskew

10,642 posts

222 months

Friday 4th December 2015
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Something that often happens on a few dual carriageways locally is that people who know the roads will get in the right hand lane immediately at the start of the (NSL) DC, because the right hand lane is for traffic turning right at the roundabout junction (half a mile or more down the road).

Happens pretty much every day, whether the DC is busy or not (it's free flowing 95% of the time), I'm always a little bit unsure as to what exactly I should do, particularly as they are often pootling along at 50-60mph tops.

LoonR1

26,988 posts

178 months

Friday 4th December 2015
quotequote all
ukaskew said:
Something that often happens on a few dual carriageways locally is that people who know the roads will get in the right hand lane immediately at the start of the (NSL) DC, because the right hand lane is for traffic turning right at the roundabout junction (half a mile or more down the road).

Happens pretty much every day, whether the DC is busy or not (it's free flowing 95% of the time), I'm always a little bit unsure as to what exactly I should do, particularly as they are often pootling along at 50-60mph tops.
What you should do is make a decision. I don't care what that decision is, just make one.