Safe Speed Forums

Looking at the OPs question there seem to be two choices being presented

1) Overtake suddenly, risking that the driver doesn't see you and then decides to swerve/turn/overtake and crashing into you

2) Make sure they know that you're there, risking that the driver may take offence and decide to speed up leaving you stranded, or deliberately ram into you or pull out in front of you.


In my experience the situation in #2 happens far more often than the situation in #1 and therefore the lower risk option is to overtake suddenly without them noticing.

Same in my experience, although the "I'm going to accelerate when he pulls out" brigade don't generally have much of a chance - the only time someone's ever caused me a problem was a guy in a V8 Jag doing 40 in an NSL who floored it as I got level with him (dangerous driving anyone?).

I generally try to get past the slowpoke before they notice I'm there and have a chance to do something stupid.

And I still can't understand why people get so offended when you overtake them. It's not like I just slept with your wife... I just overtook you, get over it!

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Magistrates rule #1: "Never let justice get in the way of a conviction."

Hazard = Risk X Probability

You state #2 has a higher probability, however dealing with it successfully, i.e. avoiding a crash, is usually much easier so the risk is lower. Each situation is different so you have to evaluate, even if instinctively[*], the safest or lowest hazard method every time. I would say on balance it is usually safer to deal with another driver being deliberately awkward than acting obliviously, in the former case, unless insane, they will not actually ram you.

[*] It is important of course that you teach your instinct or unconscious to evaluate these situations correctly

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Driving fast is for a particular time and place, I can do it I just only do it occasionally because I am a gentleman.
- James May

IMO the chances of encountering someone insane enough to try and ram you is about equal to someone deciding to pull out or overtake, then there is the additional chance of they trying to block you in.

If someone does try to block you in by accelerating, AND the sheep behind you fills in the gap you just left behind (which happens a lot) then you could end up stuck on the wrong side of the road and facing a head-on collision.

I am well aware of the dangers of the first situation. It happened to someone on SXOC a while back where they were overtaking a slow moving tractor at 60+ MPH on an SC and the tractor turned right into a field without slowing down or signalling and he ended up in the side of the tractor, but this is very much a worst case scenario, if it's another car and you're paying enough attention to not overtake near to a turning then the worst you're going to get is they decide to overtake while you're too near, and then the closing speed is your speed minus theirs, much less severe than a head on collusion.

As you say you have to evaluate each situation for itself but in the majority of them, I believe that my answer is the correct one.

Cannot say I have noticed that behaviour when I have visited South Wales, but then I was only on holiday so not in any hurry. I cannot say I have ever noticed many drivers trying to ram other vehicle deliberately. If I see two or more vehicles in close proximity I would that to be a contra-indicator to attempting a flying pass exactly because the tail vehicle may begin an overtake without looking.



Sorry if I have read this wrong, how would you be doing a flying pass with sheep following you? Do you mean to just use this as an illustration of general driver behaviour to preference to use flying pass rather than slowing, collecting and accelerating into a pass? If so then I understand your position based on your observations. The basis for my calculations is obviously different which brings up an interesting discussion in itself.



I wonder if this is an ex biker thing, I think more in terms of avoiding any impact at all rather than minimising the differential speed at impact. As I alluded to in a previous post I have usually driven vehicles with the acceleration reserves to make a car trying to block me by accelerating a non-event. I know you have quick cars from your previous posts, have you ever been a biker?

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Driving fast is for a particular time and place, I can do it I just only do it occasionally because I am a gentleman.
- James May

It's not particularly a Welsh thing. I drive all over the country and am only a recent immigrant to Wales. I find the likelihood of encountering an insane murderous idiot is inversely proportional to your distance from London.



No, I'm refering to the sheep that don't want to think so they simply follow the vehicle in front at a set distance (usually dangerously close) and match speed, and if that vehicle goes away they just close up the gap between them and the next vehicle and carry on as before.
This type of follower is common and is very dangerous if you are planning an overtake because they will close up the gap you just left, if the car you are overtaking speeds up then they will speed up too and you wont be getting your space back if you need to abort the overtake.



If you want to avoid the risk of any impact at all then you probably shouldn't be overtaking in the first place. When you decide to overtake you accept a certain amount of risk. Earlier you wrote that Hazard = risk x probability. I'd come up with a similar formular, something like Risk = Likelihood of impact x Likely severity of impact.

As a biker the formula for likely severity is probably very different to in a car. I've never been a biker so this is speculation now, but in a car, having someone pull out into the side of you isn't going to hurt very much wheras a head-on collision is going to hurt an awful lot. On a bike the head on collision is probably more easily avoidable if you do end up trapped on the wrong side of the road, but having someone pull into the side of you is going to send you off the bike and hurt rather a lot.

And yes I have a quick car, but I also have an old Volvo 940.

I have never really had the problem of a tailing car closing the gap so I could not abort, if I decide to abort it is usually quite early so they have not had time to close the gap, that type of driver tends not to react to changes very quickly anyway. I do get cars accelerating, but I tend to allow enough room for that and just accelerate harder, if they can accelerate harder than my car then it is unlikely a follower will have closed the gap anyway. The worst one I have had is when I overtook an accelerator and the car next in front apparently brake tested me as I started to pull back onto the left hand side of the road, the guy I had overtaken noticed and braked as well fortunately, it was originally a very big gap, but with one accelerating and one braking is got smaller fast. I know why he braked and I have not put myself in the same situation again, other than that though I cannot remember having any real problem getting back into a gap. I think that similarly to your reason for preferring a flying pass I just try to overtake quickly enough that the driver does not have time to mess it up for me.



Ahh, this might be it. I usually rate the chance of a head on as far lower than the chance that the car I am trying to pass will pull into my path so for me it is about minimising the time over which I could not avoid it. A flying pass with a high speed differential means that you commit to the overtake quite early, I am not talking about 10-20mph more in the 30+ region.

My Hazard = your risk, my risk = your severity - just different words for the same ideas imo. Glad we did not get hung up on semantics



What do you do if passing multiple vehicles, say six or more at one go? This assumes a nice long straight and gaps at least every second vehicle.

Whether you start with a flying pass or not do you sustain the overtake as effectively a flying pass with each vehicle or hop into gaps?

I tend to pass one or two vehicles then slow in the gap between vehicle without pulling back left into the gap, this gives me the option to abort and the time to assess each vehicle as I catch it. If the other vehicles are travelling at 40 - 45mph my speed would vary between 45 - 75 mph, I can see a clear lane in front so am safe to stay out it just lets me allow for one of the sheep suddenly waking up and deciding to overtake. On one occasion using this method let me see the line of vehicle pull out to pass a cyclist, I could easily drop back halfway into the left in a gap to let the car in front pull out to pass the cycle before I continued to pass the next cars.

I hope you do not mind me going on, it is always interesting to get a different pov at this level.

My slowest car is the Smart at about 120bhp/ton, fine for passing 40mphers from a following position, but the acceleration starts to flag at 60mph so I can see how a flying pass could start to come in for cars doing 55 - 60 mph if you have less space to use the rhs.

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Driving fast is for a particular time and place, I can do it I just only do it occasionally because I am a gentleman.
- James May

Multiple vehicles is a special case, with it's own advantages and disadvantages. I usually make a judgement as to how many I know I can safely pass and try to form an opinion as to whether the person leaving a gap is likely to let me have it. Generally if they're leaving a gap big enough to safely fit a car into without compromising anyone's stopping distance then it probably means that they actually know someone may want to overtake, they personally do not wish to do so, but are happy to allow for others to do so. I still think it should be done as quick as possible to minimise the time on the wrong side of the road and the time for them to change their mind and block the gap.

As you perform the overtake, it's also time to assess and reassess if it's safe to continue past your original planned gap (eg if you can see further ahead than you could, or if you can still see a long way ahead and no-one is coming the other way yet) on one road where I was doing this, I was able to get past about 40 cars and the 40mph HGV that was causing the queue, went through 3 speed cameras too and got a nice thumbs up from the HGV driver.

And that is the good thing about multiple vehicle queues, usually the one at the front is something like an HGV or a tractor which you can reasonably assume isn't going to accelerate suddenly, so that makes the whole event a little safer than it otherwise would be.