ADUK Archive

I thought the requirement was not to commit to the overtake prior to being sure the road in front of the car you're ovetaking is clear and reasonably sure will remain clear, for a safe overtake. As an offside view is usually necessary for that analysis this limits the use of momentum for an overtake.

MGF wrote:I thought the requirement was not to commit to the overtake prior to being sure the road in front of the car you're ovetaking is clear and reasonably sure will remain clear, for a safe overtake. As an offside view is usually necessary for that analysis this limits the use of momentum for an overtake.

Maybe so, I'm not disagreeing with you at all; but I think the situation generally envisaged prior to an overtake is that you will have been following another vehicle for a period before an overtaking opportunity arises, and therefore you will inevitably have settled into a 'matched speed' scenario.

In my experience quite a few overtakes can be assessed as you're catching up with another vehicle, and going partially or fully offside as you're closing on them. In that case there is no way I'm going to slow down and match speed with them while I have a final look before committing and going through with it. In such cases the speed differential needs to be restrained so that you can, if necessary, abort the overtake and tuck in behind your target vehicle.

In the event that your hoped-for overtake remains open for the taking, I'd say it makes sense to retain your speed and momentum advantage, and let it help you through to a safe and swift completion of the overtake; and, for those who may be interested in such factors, better MPG figures than would otherwise be the case.

Best wishes all,
Dave.

TripleS wrote:In my experience quite a few overtakes can be assessed as you're catching up with another vehicle, and going partially or fully offside as you're closing on them. In that case there is no way I'm going to slow down and match speed with them while I have a final look before committing and going through with it. In such cases the speed differential needs to be restrained so that you can, if necessary, abort the overtake and tuck in behind your target vehicle.

I agree there Dave. When you have a reasonably powerful car, ie. 0 to 60 sub 8 seconds, overtaking as per Roadcraft is relatively easy compared to slower cars, especially if they take about 14 seconds 0 to 60. This is why the increasing momentum overtake as you describe it, is usually easier. The problem is that most of the driving public are driving too close to the vehicle in front and have no view of the road ahead, (the two second rule actually doesn't allow enough gap to see sufficiently far ahead IMHO), I personally find that a gap of about three seconds allows sufficient view.

What you describe Dave for an overtaking system is the ideal for a mid straight overtake where no view of the road ahead and what is in front of the vehicle to be overtaken can be obtained in any other way.

Where possible I try to overtake at the start of the straight ie. on the bend exit. This maximises the distance available for an overtake and the necessary views as mentioned are obtained because of the curvature of the bend. If you see what I mean.

jcochrane wrote:What you describe Dave for an overtaking system is the ideal for a mid straight overtake where no view of the road ahead and what is in front of the vehicle to be overtaken can be obtained in any other way.

Where possible I try to overtake at the start of the straight ie. on the bend exit. This maximises the distance available for an overtake and the necessary views as mentioned are obtained because of the curvature of the bend. If you see what I mean.

Yes, I understand and accept what you say, John.

In my case, being confined to a low powered car, I very seldom do an overtake that involves matching the speed of the overtakee from the contact/offside position, and making no use of a speed differential.

Where possible I try to weigh up the situation as I catch another vehicle, so that I can retain a speed advantage to help me get past more quickly, without the need for much acceleration. This is the momentum overtake, as Von has previously described it, and to me it is a legitimate and useful technique, though I acknowledge the concerns, previously expressed by 7db, about the possibility of a late abort and then finding we have too much speed differential.

Best wishes all,
Dave.

I can relate to the situation that the OP has with regards to overtaking with a lack of power. I drive vehicles that can be limited in their speed and acceleration due to the weight or speed limiting devices, depending on the type of road and what needs to be passed.

In order to do it safely and easily what you first need to know is how much road you will need to get up to the speed you need to complete the overtake safely. Once you have that worked out then set yourself back from the target vehicle that distance. Coincidentally that position will afford you a good level of observation.
Once you have a sniff of an overtake, accelerate. While accelerating move towards the centre line and keep assessing. If it's still on position 1/4 of the car over. This is your commitment spot. If its still on then keep the toe in and get full offside and go, by the time you are level with the rear of the target vehicle you should be at your desired speed differential. If the overtake is not on at any stage then off the gas and drop back.

Hope that helps. It's not exactly Roadcraft but sometimes needs must.

Tosh wrote:Once you have a sniff of an overtake, accelerate. While accelerating move towards the centre line and keep assessing. If it's still on position 1/4 of the car over. This is your commitment spot. If its still on then keep the toe in and get full offside and go

I agree that when you don't have gallons of power on tap for a triumphant point and squirt, a bit of speed differential prior to committing can help (cue 7db to remind us all that you are committed as soon as you could no longer stop behind them if they braked hard), but why not go fully offside before deciding? It's almost certainly going to give you an even better view. What's the benefit of restricting yourself to the view from only 1/4 offside for the go/no go decision?

If you're offside when the other driver brakes you wont need to stop behind them?

Do you think most drivers could avoid a collision if the vehicle ahead brake hard with a 1 second gap?

GJD wrote:

Tosh wrote:Once you have a sniff of an overtake, accelerate. While accelerating move towards the centre line and keep assessing. If it's still on position 1/4 of the car over. This is your commitment spot. If its still on then keep the toe in and get full offside and go

I agree that when you don't have gallons of power on tap for a triumphant point and squirt, a bit of speed differential prior to committing can help (cue 7db to remind us all that you are committed as soon as you could no longer stop behind them if they braked hard), but why not go fully offside before deciding? It's almost certainly going to give you an even better view. What's the benefit of restricting yourself to the view from only 1/4 offside for the go/no go decision?

I'm only in the 1/4 offside position until I have roughly half the speed I require for the overtake. Then if its still on then it's full offside for a good look and continue to build the full speed differential required for the overtake. To try and build up all your speed on the offside would mean a very long time spent on the wrong side of the carriageway!

Tosh wrote:

GJD wrote:

Tosh wrote:Once you have a sniff of an overtake, accelerate. While accelerating move towards the centre line and keep assessing. If it's still on position 1/4 of the car over. This is your commitment spot. If its still on then keep the toe in and get full offside and go

What's the benefit of restricting yourself to the view from only 1/4 offside for the go/no go decision?

I'm only in the 1/4 offside position until I have roughly half the speed I require for the overtake. Then if its still on then it's full offside for a good look and continue to build the full speed differential required for the overtake.

The question is where in that sequence do you make the decision whether to pass or not? That decision doesn't have to happen before, or at the same time as the decision to go fully offside. Often better if it doesn't happen until afterwards.

Tosh wrote:To try and build up all your speed on the offside would mean a very long time spent on the wrong side of the carriageway!

So?

I guess that you could adjust the sequence and the decision making point to anywhere you feel comfortable within the process. Thats what I do. I just take each one as it presents itself and decide on the best plan of attack.

GJD wrote:

Tosh wrote:Once you have a sniff of an overtake, accelerate. While accelerating move towards the centre line and keep assessing. If it's still on position 1/4 of the car over. This is your commitment spot. If its still on then keep the toe in and get full offside and go

I agree that when you don't have gallons of power on tap for a triumphant point and squirt, a bit of speed differential prior to committing can help (cue 7db to remind us all that you are committed as soon as you could no longer stop behind them if they braked hard), but why not go fully offside before deciding? It's almost certainly going to give you an even better view. What's the benefit of restricting yourself to the view from only 1/4 offside for the go/no go decision?

I find in some situations I can only go partially offside initially, in order to verify that it is safe to go fully offside to get the complete picture. On the other hand I might be using a faulty technique; but no, I'm sure it can't really be that.

TripleS wrote:I find in some situations I can only go partially offside initially, in order to verify that it is safe to go fully offside to get the complete picture.

Of course. I bet in those situations, you don't decide "I'm definitely going to pass this fella" while you're still thinking "I'm not sure whether it's safe to go fully offside here".