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This is a page where you can get away from my personal opinions and read what experts have to say. The copyright of these pieces remains with the authors.

Do we need progress? David Wornham

Smoother gear changes John Gruffydd

Re-running the System Alan Russell

 

Do we need progress?

Observers occasionally, but regularly, receive queries from Associates on the real need for "progress" when we encourage them to drive up to the speed limit whenever it is safe and appropriate to do so. It is said that we should be encouraging more economical methods of driving and I agree that, not only we should, but indeed do so. This is best done by gentle acceleration, earlier easing off the accelerator pedal before gentle braking, using flexible gears by not changing up too soon to avoid labouring the engine (which is less apparent in modern cars), anticipating hills and bends and by not using lower gears as a means of slowing the vehicle.

It is worth reminding all that we aim for a standard to pass the Advanced Driving Test and, to become Advanced Drivers, we must prove our competence at higher speeds within the Law and safety. However, we must also remember that true advanced drivers are able to adjust their driving not only to the road, weather and traffic conditions but to suit the needs of loads and passengers. We may choose, quite properly, to drive gently when chauffeuring, sight-seeing, with senior citizens, car-sick-prone children or fragile goods  and when we realise, with increasing age, that our observation, anticipation and reactions are becoming slower. We must not forget, however, to watch for tails of traffic and use of lay-bys or junctions to let them pass. So why the need to prove the ability to "progress" to pass the advanced driving test?

Let's put it this way. We, as human beings, are "designed" to travel no faster than running speed which I guess will vary around 10 mph. However, when driving, we are throwing ourselves along the road in a tin box at speeds of up to 70 mph so we have to learn to adapt our thinking and reactions to cope. Do you remember how it felt to drive following the last time you had a two week holiday without driving? A little quick, I expect, as you became re-accustomed to the faster speed. If your driving is always a sedate 45 mph and you are called upon to take a sick relative urgently to hospital you will naturally wish to drive at a faster speed. If you have no recent experience of driving at 60 to 70 mph it may well be that you become a far greater hazard and your potential life saving journey becomes a life threatening one!

Another point in favour of developing brisk progress is that the skills of reading and driving smoothly through corners need to be enhanced at higher speeds and the results of bad planning are more readily felt at higher speeds so enhancing the learning process but, hopefully, only by discomfort rather than leaving the road!

A few words of warning on over-use of progress. Having successfully completed the advanced driving course we have proved our capability of using progress safely, comfortably and legally. Let us all be aware of the danger of over confidence. Reading the limit point of bends well, driving around them under perfect control and vehicle balance is fine, but if we forget the golden rule of always driving at a speed to be able to stop easily on the correct side of the road in the distance we can see to be clear (or, in the case of single track roads, at half that speed) can lead to a crash and the title of "Former Advanced Driver"! My favourite words to remind me of this is "tree trunks" meaning that, around every bend or brow of a hill there may be a fallen tree blocking the road. The question "can I stop?" often leads to a little less pressure of the "gas" pedal!

Don't forget: Keep it on the black stuff, preferably wheels downwards.

David Wornham
Worcestershire Group of Advanced Motorists

    (Do visit our guest contributor's Group website)

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Smoother gear changes

What we're trying to avoid, at all times, is jerk. How can we define jerk mathematically? Just like speed (OK, velocity if you want to be pedantic :-) is rate of change of position and acceleration is rate of change of speed, so jerk can be defined as rate of change of acceleration ("s triple dot" for the mathematicians). So what we're trying to avoid is a sudden change of acceleration. If acceleration (i.e. depressed accelerator) is maintained right up to the point at which the clutch is disengaged to change gear, the acceleration is suddenly removed, we sense a forward jerk (the 'nod' that others have referred to). Even worse, if we mistime things a bit so that if the person's body and neck are just moving forward and accelerator is re-applied, the poor passenger sinks back rapidly. It really is uncomfortable. (It's worse for a passenger because he/she is not aware of when these things are going to happen). So it's not the actual acceleration that's the problem, it's rate of change of acceleration.

The same applies to braking: if you maintain the pedal force right up to the momemt of stopping, the deceleration suddenly stops and the car and its passengers jerk back at the moment of stopping. That's why we feather off the brake just as we come to a stop. Let's look at a smooth upward gear change (say 3rd to 4th) in "slow motion". Just before the gearchange, smoothly back off the accelerator so that the car is not being driven by, nor driving, the engine. At this point the clutch is depressed and, if things are right, the engine speed will not change. As the lever is being moved from 3rd to 4th, relax the accelerator a little more so that the engine speed has now dropped to that which will be needed when the clutch is released again, at which point the engine speed still should not change. Only then should the accelerator be depressed progressively to accelerate again. This is perfection, and nobody will perfect it every time!

I find the main fault during gearchanging is that the driver releases the accelerator far too much (right off even) when the clutch is depressed, so that when the clutch is released again the car has to drag the engine back up to speed. If this fault can be cracked, we're well on the way to a smooth drive.

John Gruffydd
Membership Secretary and Chief Observer
Chester and East Clwyd IAM Group

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Re-running the System

There is one sentence in Roadcraft that every observer, and every associate who has read it, must have briefly pondered. Yet surprisingly few seem to have given it significant attention in places where IAM members foregather. It appears on page 23, at the end of the two excellent paragraphs which introduce the System of Car Control. Here it is. "If new hazards arise, you adapt by reassessing the situation and reapplying the System at an appropriate phase."

Two questions arise from this.
 (1) For any driver (or biker): How do I tackle this, both in general terms as something I can prepare myself for, and for any observer: How on earth do I put this across to my associates?

I hope the following thoughts will make sense to both groups of road user. First I shall take the Roadcraft statement at its face value. With the exception maybe of professional instructors (e.g. at police driving schools), few if any are likely to carry out practical instruction on this point on an organised basis. Situations in driving where the traffic circumstances change, and where a re-run of System is needed, will take place too fast for all but the most highly skilled instructor to handle effectively. (Permanent situations, e.g. arising solely from road layout, are another matter. There may well be some observers who build these into their box of tricks, and take associates through them in order to show something of how to handle a System re-run.) Therefore, the best that observers out on the road will generally be able to do when the need for a System re-run unexpectedly arises is to advise the associate to come to a halt, and then carry out a post-mortem. Even this will demand high levels of alertness and intelligence!

In fact there is another approach to the whole thing. To think about the System in this context, and about how we repeatedly use it as we drive or ride along, it helps if we do not view it as a checklist to consciously run through over and over again. Yes, that is what is printed in Roadcraft, and that is what each one of us once used, carefully and deliberately, as the basis for our current package of road skills. But what did that printed checklist provide for each of us, when we worked to incorporate it into our driving and riding? It enabled us to adapt the package that we already used, ending up with what we will all agree to be a superior one: a complicated, closely-knit and highly refined package of conditioned reflexes. As we drive today, having mastered the System and become fully competent in its use, this is the package that we use. Now, in every new road situation that we meet, we call upon it to enable us to negotiate the hazards safely and efficiently. This is how we use the System - by calling on the relevant conditioned reflexes, not by repeatedly thinking about Phase 1, Phase 2...

The rationale which underlies the System is based upon certain hard facts - Newton's laws; the basic design and operation of motor vehicles; the nature of the hazards that drivers and bikers are liable to meet; the value of habit; and so on. Each one of us, as we have continued to build up our unique personal package of reflexes for our driving and riding, has added our own take on these things, and this will affect the precise ways in which at each hazard we put the System into practice. And our personal use of the System will also be an expression of our personal values with regard to a sense of responsiblity - other road users - the law - and so on. It will involve our appreciation of our own skills and capabilities, both in general and on the day in question. I could go on.

So when each one of us uses the System, we are using our own private interpretation of it, and any subtle ways in which we may have developed it, consciously and unconsciously, for better or for worse, up to the present moment. Now, in my opinion, if we follow through all these things carefully and consistently when we are at the wheel, the end result is going to be indistinguishable from a 'systematic' drive. But words such as 'System' or 'Phase 1' may never enter our head for days or weeks on end. What I think I am doing in just about all of my driving is not going consciously through the checklist of the System, but simply doing what makes best sense to me at each moment. We use the System to teach doing what makes best sense to our associates. True, there are times when I think carefully about the checklist of the System as I drive - but I do this, I believe, in order to maintain my standards and not become sloppy, rather than in order to tackle certain specific hazards that I am faced with.

Let us now come back to the question of the System re-run. I think there is a danger that observers who are not pretty sure of what they are doing may get tied up in a confusing discussion of Phase 3, Phase 4 or whatever, and end up suffering the fate of the mythical Oozlum bird. Not the best way to encourage our associates. On the other hand, if we can sell to associates the idea of doing what makes best sense at each moment - including when the circumstances change - then I think the whole issue takes care of itself. And maybe this is why, as far as I am aware, observers generally have not found it necessary to get to grips with it on a formal basis.

(Note on punctuation. Roadcraft uses lower case throughout for 'the system of car control'. Roadcraft is wrong.)

Alan Russell
Past Training Officer with Manchester and Salford Group of Advanced Motorists and with Salford Advanced Motorists

 

 

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