The Cost of Road Pricing and the Value of Efficiency

There is certainly a need for a fairer system of road user charging over and above that produced by road tax. However, in order to achieve it, the government is unlikely to introduce an expensive network of road tollgates similar to those seen elsewhere in Europe. Current thinking seems to be with technology in the form of static cameras and automatic number plate readers.

While devising a suitable method of charging that will see all road users pay up, including foreign registered vehicles, should be a priority, there is another important issue here. The technology route of monitoring vehicle journeys allows an opportunity to encourage efficiency in road transport operation. Cameras linked to dynamic weighbridges, or maybe on board telematics, used to monitor laden journeys will inevitably increase efficiency when linked to the charging scheme. In direct conflict with the logic of road tax rates, laden journeys encouraged by reduced charges could see important environmental issues addressed.

All this may involve extra cost but the value of utilising camera equipment on a broad base could justify the price.

An Image to Die For

Why is it that whenever I look at a modern sports motorcycle I think it wants to bite me? Maybe it’s the headlamps, like eyes scowling from the front of the fairing; or those indicators and grills, like talons and teeth waiting to grab me. Whatever’s creating it, there’s an impression of attack, of aggression and hostility. But if this truly is the intention, what is it for?

Despite only accounting for one percent of the total number of road users, motorcyclists suffer nearly twenty percent of all road death. It’s not young riders either, most casualties are among higher age groups, those that can afford to buy and run powerful machines. And the accidents are not necessarily at night when visibility is poor or due to the rider losing control.  Many happen during the day, in fact, fatalities involving motorcycles are more likely to happen at road junctions on weekdays, where the machine is in collision with another vehicle. So, is this the reason some motorcycles seem to be on the attack, as a way of dealing with such a hostile environment, one where the odds are stacked so heavily against them?

Certainly when you look at the naming of some bikes, you get the impression that they are set on a path of confrontation rather than appeasement; a show of might that will not only warn of their presence but also challenge any other road user that gets in the way. Triumph, for example, has a motorcycle called the Street Triple - not the Avenue or Road Triple; this bike is on the ‘streets’, the tough and unforgiving world of the imagination, where a man wants ‘respect’. Similarly, Honda has the Fireblade, Suzuki its Bandit and Kawasaki the Ninja, all designed to ‘meet-head-on’ and not wait around long enough to become a victim. Even race track inspired motorcycles have names associated with predator dominance rather than the superb technology of the machines themselves. Suzuki’s Hayabusa is named after the fastest bird of prey in the world, the deadly Peregrine Falcon, and its front fairing and headlamp are shaped to be very hawk like. But, as in all cases, attack is only really sensible when the enemy is weaker, or at best equal in strength.

Stealth is something much sought after in military terms and, because of their size, motorcycles have stealth by the bucket load. The Americans have invested billions of dollars in the development of ‘invisible’ bombers, and the result has been machines that are capable of delivering a decisive victory; of winning – they have an excellent chance of coming off best. Some sports motorcycles have lots in common with the stealth bomber: they are aggressive and moody looking; they have suitably bellicose names; they are operated by people with black helmet visors; and they are very hard to see, especially from other vehicles they are travelling towards. And it is for this reason that the similarity ends because the motorcycle, in contrast to the bomber, is often destroyed in the attack and its pilot sometimes killed. So, with this in mind, there’s probably something wrong in trying to create an image of warlike response to the motorcycle’s plight on the road.

Naming a motorcycle Ninja or Bandit or referring to a machine as a ‘street fighter’ is like calling a ship Titanic – it’s asking for trouble. Ships should be given names like, The Saucy Sue, an almost silly little monocle that accepts vulnerability, one that in reality is saying, Dear Sea, You Are All Powerful, Please Don’t Let Me Sink. Motorcycles should then be called things like the Blythe Spirit 750, or the Lady Jane 400, sending a message to the rider that their machine is a respectfully passive object in a hostile world. Whether the motorcycle’s image creates the rider or the rider is simply getting the motorcycle that reflects their own attitude does not really matter, it’s an obvious mistake to make bikes that seem to be on a war footing. With the right approach, headlamps on and keeping a constant lookout, man and machine should be able to successfully navigate any danger.

The Uncommon Market

Why is the curtains sided trailer the most common trailer in general haulage? Because industry has created a trailer that is the most efficient way to deliver goods. Why can the legislators in Brussels create new regulations that improve road safety? Because industry has developed systems that have such an effect on safety that they become mandatory. So it seems strange, in view of this apparent connection between commerce and law, that Europe is now trying to tell us that we cannot use trailers of more than four metres in height.

Innovation in vehicle design has always been led by the business market, whether through improvements in efficiency or safety. From curtain trailers to electronic stability programs, maximising efficiency has been the goal and by embracing technology the industry has achieved success. Technology in safety systems has prompted legislation that will eventually make whole areas of enforcement redundant. Technology in logistics has created systems that have made some of the more traditional methods of controlling efficiency outmoded.

So, with ABS, EBS, variable cruise control, lane departure and roll stability programs keeping our trucks safe, and GPS, telematics and remote intervention ensuring that our trucks are where we want them to be, why is Brussels still thinking in such basic terms as ‘standardisation’? Standardisation belongs to an analogue age as outdated as the Soviet Union, a relic of the past when manufacturing was limited to generic customer demand and the best way to sell was to offer any colour as long as it was black. Today, diversity is king and current technology must surely lead to individual states being able to implement effective logistical systems that allow them to use the most appropriate vehicles for their particular traffic network. Where operators work across the EU, the market will dictate individual vehicle purchasing decisions and technology will ensure safety while keeping track of logistics. Where maximum height trailers can be used, they should be used. (Where B–Trains or ‘pocket’ road-trains are acceptable, they should be accepted.)

In the interests of the whole community, Brussels should recognize their responsibility and leave efficiency to innovation and the market – not the Common Market, the free market, about which nothing has to be common.

Take a Brake

A long time ago now, I made a terrible mistake. A mistake that has, however, stood the test of time; a mistake you’d think would have been eradicated ages ago judging by the pace technology moves. But no, it’s apparently something that still happens today – you only have to look at some of the literature bunged out by the DSA and VOSA to see that.

I’d passed my test not long after my 21st birthday and was soon driving artics for a haulage company based in south-west London that specialised in machinery transport. The thrill of seeing all that vehicle behind you in the mirrors, and a tightening of the stomach when you arrived at a drop and were shown where you were expected to reverse into, had yet to pass. I could change gear without coming to a halt first, just - although I would still occasionally miss a gear on a steep hill and have to stop, select crawler and start again. I was new, inexperienced, young and keen. I was to mistakes what a match is to a petrol bomb.

I arrived back at our yard one evening after a couple of days ‘up the road’ - a phrase I’d heard the older drivers use and had latched onto with relish, along with other essential terms, such as, ‘trombone trailer’, ‘skelly’, ‘tipped’ and ‘he’ll never make a lorry driver while he’s got a hole in his arse’. Our yard was on an incline, and I reversed the lorry up this slight bank and parked it opposite the fuel bunker, which was encircled by a reinforced concrete wall.

I went to the office and picked up my instructions for the following day. I was tired: it had been a hard day, tipping after a long drive. I could have done with a break, a cup of tea, a proper sit down. But this was exiting. I was to go farther north than I’d been thus far. I was to carry plant. I needed to change trailers, so I dropped the flatbed I’d used that past week and hooked up under a step frame low-loader - a real trailer. I strutted, climbed up onto the load-bed and surveyed the expanse of metal and wood before me, moved chains from the front to the back and then back again, and made the noise of the heavy hauler at work.

I had soon placed my number plate in the holder at the rear of the trailer. Afterwards, I walked forward, wound up the short legs, connected the suzies and got into the cab. I had decided to fill up with fuel for the next day, so I released the park brake and made to pull forward. Nothing; we were riveted to our spot. After a moment’s thought, I realised the problem: the trailer’s mechanical brake was still on.

No trouble. I leapt out of the cab and went to the rear of the trailer. I could see why I had missed it: the lever was tucked right out of the way compared to the ones I was used to. Clunk, the brakes were off. I turned to walk back to the cab but something in the corner of my eye caught my attention. It was the wheel nuts of the trailer, they were moving. It took a fraction of a second for me to realise what had happened: in my haste, I’d not reset the tractor unit’s park brake. With all that weight behind it, and on an incline, the lorry was off on its own. I needed to apply the vehicle’s brakes somehow, and quickly.

The whole combination gathered a momentum that seemed to herald my doom. Every block of tread on those tyres that stamped a new print in the mud of the yard as the wheels turned, would help to stamp ‘sacked’ on my CV. Soon, reinforced concrete and fibreglass would meet in battle. The result: Mike Tyson verses Julian Clary. It would be no good saying, “Oh well, it’s only a Seddon Atkinson”, this was 1978; they were up there with the best of them. I’d be laughed at from the café to the pub. I’d be given a nickname that would remind me and everyone who heard it of that day. I was finished.

I now wished I didn’t have a hole in my arse, and not just because it might mean I would eventually become a real lorry driver. I panicked and started to bolt for the cab. If I could run round to the driver’s door, I reasoned, open it and climb up, I may be able to get the park brake on in time. It was too far, and I was hardly making progress against the speed of the lorry. The catwalk! I’ll climb up and remove the red line. No, too difficult, and what if I fumble with the connection.

The cab seemed miles away. I could see through its rear windows; I could see my furry dice hanging down in the centre of the windscreen; I could see the top of the driver’s seat and its head restraint - oh how I wished I was sitting in that seat. It came to me that there was one opportunity left, and I took it. I turned back towards the trailer brake.

With several tons of heavy trailer pushing down the slope, the vehicle had quickly built up speed. I focussed on the lever below the trailer and lunged at it in a sort of athletic back flip I couldn’t imagine ever doing before or since. With my left hand gripping the side of the load-bed, my body hanging backwards on my left arm and my legs stretched forward, feet digging into the mud, as if I was trying to physically stop the whole shooting match Mr Incredible fashion, I reached out with my right hand and grasped the brake handle.

I wound against the ratchet like a man possessed. I couldn’t see the cable and the slack I needed to take up. In-out, in-out, my frantic action went on for an age. I thought the cable must be broken, maybe it had snapped somehow. I felt the rotating tyre next to me chaffing against my shoulder, as we, the lorry and me continued, onward to our destiny of shattered dreams and broken glass.

I closed my eyes and imagined the first crunch. As the metal bumper and headlights impact the wall, the glass shatters and the bumper and its mountings twist and buckle with a deep cracking sound. The headlamp glass is insignificant compared to the mass of fibreglass and metal of the cab, and the sound of them breaking is lost amongst the splitting and tearing that follows. Just as I think it’s all over, and with the timing of the very best ‘main acts’, the windscreen pops from its mounting in the still twisting shell of the cab and belly flops onto the wall below. It’s all over in a couple of years, or was it just a second or two?

But, as I lay there, flat out on my back in the mud and next to the mercifully still trailer, I saw that my worst nightmare had failed to materialise. We’d stopped short of the wall. I breathed a deep sigh of relief and stood up. I looked about the yard, prepared to be ‘Pratt of the Week’, but not, now, ‘…of the Decade’, or ‘…of the Entire History of British Road Transport’. There was no one. No one had seen me elevated to the heights and then reduced to the lows in my first truck driving job.

Now, when I look at a trailer, an image comes to my mind of that day, all those years ago – the view through the back windows my disappearing cab. And sometimes I ask myself... what did we ever see in furry dice?

The Road is Long ...

The lecture was being held in the usual place: at the rear of a public house just off the Great North Road. The room set aside for such occasions was comfortable enough but often musty with the scent of old wood and dampness; probably due to a lack of use and investment since the motorway was finished a number of years ago. I often try to imagine the place back then - when it was in full swing and before the new road took away most of its custom. A busy passing trade mingling with the locals, thriving on a stream of new faces, revving engines, alcohol and the music of that era, the 1970s. As I drove across town from the road that had put an end to all that, hoping to arrive at the meeting at just the right time – not too early and definitely not late - I could feel the contrast between the modern road, its bright lights and wide tarmac, and the narrow dullness of the old town, where I was now headed.

I parked in the car park and walked the short distance to the entrance, a huge oak door and stone surround; a facade that spoke of grander times. Though now shabby with worn, cracked steps and dulled, peeling varnish, it still retained a certain dignity. It struck me that instead of the name of the pub engraved in the stone above the door, it should have the words ‘The Road is Long’, a testament not just to the great road it once served but to the place itself, for enduring quality, charm and longevity. And for its relevance, even today. When floor-to-ceiling tinted glass and stainless steel framework goes out, then maybe the natural benefits of stone slabs and heavy woods will be back. Whatever the future brings, the place had stood the test of time and still worked – even if it was a bit dated.

The Institute provided speakers on a regular basis - and tonight was to be a feast for those interested in Professional Development, with a talk from one of the world’s leading truck manufactures about modern electronic systems. I went along for interest only - age and professional saturation had made the prospect of any development an irrelevance some time ago. I took my seat close to the back, as normal, and surveyed the rest of the night’s audience. There was the usual bunch – fitters, technicians, managers - most at the start of, or at least at a stage in their individual careers where they felt they could make a difference. The youngest sat at the front, the middle aged, middle managers in the middle, and the rest at the back. The speaker (young, an air of intelligence and seriousness) was introduced by our regional secretary (grey hair, pinstripe suit, retired but hanging on), who was also acting as Chairman for the evening. The lights were dimmed to help out the screen onto which our guest’s presentation was to be projected. We were told to expect information on the very latest in technological advances in vehicle electronics from a man who knew his stuff, an expert in the field. And so the lecture began.

Multiplexing, he told us, not only reduced the amount of wiring needed but more importantly, allowed different components to communicate with each other. Imagine, if you will, he said, the lights knowing that the wipers were on. I tried. Then, imagine that the wipers were on ‘max speed’ – hey presto, the lights come on without the driver touching a button. Why? Well, if the wipers are on full visibility must be bad, hence the need for lights. I was impressed, and so were the others. I could see the young blood moving forward on their seats, as if closer proximity to the speaker would somehow anoint them with his knowledge. Digital wiring, apparently, was in. “If driver don’t know he needs lights on, shouldn’t be drivin’ in first place.” A voice said from somewhere in the audience. I looked around in the direction it had come from and saw its origin a few seats to my right, just across a small isle that ran down the centre of the room. The rest of the group had also turned to look, but they didn’t linger – the real attraction was at the front and heads were soon nodding in agreement once again to ‘the message’. However, I couldn’t help but stare a while longer at the figure sitting there. The voice belonged to a rather small, slightly bent, elderly man who ever-so gently rocked backward and forward on his seat. He struck an odd figure, even in a group so varied in age, and what would once have been referred to as class, as us. His clothes were old but spotlessly clean, his shoes highly polished but badly worn. He wore a tie but with a thick winter shirt, the type not often seen now that we have fleeces that need little underneath. His trousers looked formal but he wore no jacket, just an old anorak and cardigan. He looked out of place amongst the polo shirts and neatly pressed denim that surrounded him.

Eventually, I looked to the front and reconnected with the group. Rollover, we heard next, was of great concern, and very expensive. Murmurs of agreement came from middle managers, both existing and aspiring. Speed and cornering were apparently the danger areas. ABS wheel speed sensors combined with lateral acceleration sensors, linked to processors would monitor stability and ... . He didn’t finish. The Voice, not loud but clear enough, didn’t let him. “Take away power steering, that’ll slow the buggers down on roundabouts”. This time our guest lost a little of his thread and looked a bit taken aback. The Chairman smiled reassuringly at him, raising his eyes to the ceiling momentarily in a gesture of solidarity in the face of such adversity and nodded for him to continue. The speaker rallied, bolstered by the obvious contempt shown by the majority of his audience for this unwarranted interruption.

We soon moved on to electronic pneumatic braking and the advantages such a system brings. Faster application and integrated electronics meant efficient, safe braking. The Voice had his own opinion. “Bring back the blue line”, I heard him say (a reference to the old three-line air brake system fitted to British tractors and trailers). Sharp looks but no words came from the front. The untold benefits of variable cruise control were next on the agenda. We heard how by setting the distance between our truck and the vehicle in front, we could rely on the computer to keep us safe. Even the sudden appearance of another vehicle from a cut-in manoeuvre wouldn’t fox it. Cameras would detect the position of other road users and activate the pre-crash systems if needed, pre-tensioning seat belts and lightly applying brake pads in readiness. “Glass cabs, that’s the best answer. Give ‘em glass cabs. They’d keep a fair distance from other motors then”. The Voice had spoken once again. This time no one turned to look, although there was a lot of sighing, especially from the front - and a few grins from the back.

The lecture finished not long after and the floor was thrown open to questions. They came thick and fast. What diagnostic kit did our expert recommend? How was interference dealt with by the wiring system? What was in the pipeline for the immediate future? And finally, what fitment, in his opinion, would make the greatest contribution to safer driving? I have to admit, I wasn’t at all surprised when The Voice answered for him. “A bloomin’ great spike in middle of steerin’ wheel”, it said. “The point restin’ against ya chest”. A few, including myself, nodded in agreement, and allowed ourselves the luxury of a chuckle.

The evening came to an end and our Chairman thanked the speaker once more. I got up and looked around for The Voice, but of him there was no sign. I left without staying for the social part of these gatherings that usually followed on from the night’s talk. My car soon warmed up as I headed home along the motorway. I set the cruise control and the air conditioning and the radio to how I wanted them, and sat there... and sat there.

Sir Isaac Newton, Furry Dice and Trucks that Roll Over

Imagine that today you are going to do something different to earn money for the taxman. Instead of driving your truck you are going to ride The Wall of Death, a motorcycle stunt once common at fair grounds. Spectators would stand on a platform at the top of a large, upturned cylinder, like an enormous bucket, inside which a motorcycle was ridden round and round, rider and machine horizontal, as if stuck to the wall. It may not be too different from what you are used to: certainly, the person who owns the machine and who sets you off on your journey will be more than happy that they are staying behind. But that’s not the only similarity, the laws of nature that will keep you and the motorcycle from falling to the bottom of the bucket are the same as those that keep your truck on the road.

About 300 years ago, Sir Isaac Newton discovered that when an apple becomes detached from a tree it falls to the ground. Not much of a revelation you might think but Sir Isaac went on to describe three basic laws of motion that are still used today. Briefly, Newton stated that a body in motion would continue in a straight line unless acted on by an external force; that acceleration will be in the same direction as any force applied; and that every action has an equal and opposite reaction. These laws are true for all bodies: planets and people, rockets and trains, trucks and motorcycles.

So, as you ride the motorcycle round The Wall of Death, it is Newton’s Laws of Motion that should provide a description of what’s happening; and by climbing on the motorcycle, you are going to put Newton – and yourself - to the test. You start by riding round the small ramp at the bottom of the bucket until your speed is high enough for you to ride up the wall. As the speed of the motorcycle increases, the affect of the force working to the side gradually catches up that of the force that is trying to pull you down to the ground (your weight). Once the effect of the side force overcomes that of your weight – and, of course, that of the motorcycle – you are stuck to the wall. And you ride round as if suspended in mid air, marvelling at nature and Newton.

You are now travelling at a constant height from the base of the bucket and at a constant speed. To you, riding at 90 degrees to the wall, as if it was a road, is like climbing a hill that never ends. You feel a force acting on you, pressing through the seat of the motorcycle. You remember what Newton said: that you will continue in a straight line unless acted on by an external force, and that any force applied will have acceleration in the direction of that force. The external force provided by the wall is continually changing your direction by pushing you toward the centre of the bucket. It’s like what happens with a hammer thrower at the Olympics. The athlete spins round and round with the hammer on the end of a cord. The hammer is kept in circular motion about the athlete by a force transmitted through the cord, which, like the acceleration, acts in the direction of the athlete. The hammer wants to go off at a tangent but cannot until the athlete let’s go.

Back on the wall, the acceleration and force may be acting towards the centre of the bucket but you also feel a reaction, pushing you into the seat of the motorcycle. This is no surprise; Newton has told you that every action has an equal and opposite reaction. (It’s this reaction that is sometimes called centrifugal force, a pseudo force that in reality doesn’t exist. The real force, as we have seen, acts towards the centre of the circle, and is the centripetal force). One thing that does surprise you, however, is how much the force increases with little increase in speed. It seems to you that with only a small twist of the throttle you are pressed against the wall with such force that the two cannot be directly proportional to one another – and you are right. Speed has a squared relationship with side force: double the speed and the force increases fourfold.

Surviving the wall you’ll be happy to be back in the safety and comfort of your truck. But don’t forget, the laws of motion that applied in the bucket apply everywhere. When attempting to negotiate a bend, Newton tells you that it will take a force to alter the original course, and if you want that direction to continue to change, and you will as long as you are in the bend, the force must remain. Now, instead of the wall creating this change in direction, the truck’s tyres apply the necessary force, accelerating you towards the centre of the circle. If the side force becomes too great, then just like in the bucket, it will overcome the effect of the weight of the vehicle. This time, however, it doesn’t provide stability; it destroys it and the truck rolls over.

In the days when no self-respecting Leyland Marathon or Ford Transcontinental would be seen without a set of furry dice hanging down the inside of the windscreen, the driver had an instant indication of the effects of Newton’s laws. As the tyres forced the truck into a curved path, the dice were the last things to follow on, appearing to swing in the opposite direction to the truck’s turn as they attempted, in reality, to travel straight ahead. The greater the side force, the greater the angle of swing. It’s hard to imagine how you could compare the forces acting on a pair of furry dice with those acting on a truck, until you remember your experiences in the bucket. When you increased speed, the side force increased, but there was no change in mass – you and the bike remained the same; no new material was added to either of you. The increase in force was purely down to an increase in its acceleration and the only things that affect this lateral acceleration are the radius of the curved path and the speed at which you travel round it.

This result is very useful: it means that when considering a vehicle’s stability, we can (in most areas) disregard its mass and just concentrate on accelerations. We know that a side force acts on the vehicle as it travels through a bend, and that there is acceleration in the same direction as the force. We also know that the vehicle’s weight is a force and that force has an acceleration; the acceleration due to gravity. So, as your truck travels through a bend, the lateral acceleration and how it compares with the acceleration due to gravity are all we need concern ourselves with. The dice will have the same accelerations acting on them, as they are attached to the truck, and although the force acting will be vastly different, the lateral acceleration and the acceleration due to gravity will be the same for a 44 tonne truck as they are for the 4 oz dice. All the driver need to do is watch the dice as the truck settles into a bend and see how far they swing to one side. This will give an indication of how much acceleration there is to the side compared with how much there is pointing downward.

It is actually similar in principle to how a tilt-test for vehicle stability is conducted. When a vehicle is placed on the platform, the coordinates of the resultant force are compared as the bed is gradully tilted.  The component of lateral acceleration (a) can then be expressed in terms of the component of the acceleration due to gravity (g). This gives a static stability factor ‘a’ over ‘g’ (a/g). However, this figure will be reduced when the vehicle is on the road for reasons that will be mentioned shortly. In theory, you should be able find the a/g factor that the truck is actually experiencing by measuring the angle the dice make to the vertical as you drive it through the bend, and then find the tangent of that angle. How much could the dice lean before the truck becomes unstable? Unfortunately, it will depend on a number of things.

There’s an added complication with any road vehicle because of the position at which the lateral acceleration (and, therefore, the side force) acts. When you rode the motorcycle around the inside of the bucket, the lateral acceleration created by the wall worked straight through the centre of gravity of both rider and machine, and the point the motorcycle touched the wall. The reaction worked in the opposite direction along the same line. Now, the lateral acceleration created by the truck’s tyres at ground level is being transmitted to the vehicle’s centre of gravity, which will be at some height above, and something similar to a leverage forms. As the vehicle travels round a bend, this leverage is working on a pivot point at the outside tyres. It is being countered by the acceleration due to gravity trying to lever the truck downward, again acting at the centre of gravity and about the same pivot point. So, now it’s not just the size of these accelerations that is important, it’s also the size of their leverages. If the leverage of the lateral acceleration is greater than that of gravity, the vehicle will become unstable. In a car, which will have a wide track width compared to the height of its centre of gravity, the leverage of the lateral acceleration never manages to exceed that created by gravity. Lateral acceleration builds until the tyre friction limit is reached and the car slides sideways. In a truck, the leverage of the lateral acceleration will usually exceed that of gravity before the limit of tyre friction, resulting in rollover.

It’s not only the height of the centre of gravity that can have an affect on rollover. Anything that causes extra body roll will assist the lever trying to pull the vehicle over by reducing the righting affect of the vehicle’s weight. Soft tyres and weak suspension, or a heavy load, are prime candidates, as is an offset or shifting load. And, as with most things, it’s never that simple. Factor in rate of change in lateral acceleration associated with some manoeuvres, the resonance of steering input with suspension frequency during sudden lane changes; and the bucket and motorcycle job doesn’t seem that bad after all. But don’t give up on truck driving too soon; there’s plenty you can do to reduce the chances of rollover.

If the truck’s stability a/g drops during cornering or the a/g it is experiencing climbs, the two factors will converge. If they meet - or worse, the truck’s stability is exceeded – you’ll probably wish you were back in the bucket. So, the lateral acceleration it is experiencing needs to be kept as low as possible and the lateral acceleration it can withstand will need to be kept as high as possible. The former is down to speed and the importance of the squared relationship it has with side force (and, therefore, lateral accelleration). Whatever lateral acceleration your speed creates has to be resisted by the trucks stability and this will decrease for a number of reasons, the most important being the height of the centre of gravity. Ultimately, the probability of rollover will only be avoided completely by careful monitoring of a/g factors, either by you or, if you’re not too good with a protractor under conditions of extreme stress, a stability program. I think I know what the answer is.

ENERGY: Life in the Machine.

There’s a fundamental truth of nature that is not often quoted. Maybe because it’s simply stating the obvious, or because it’s implicit in some of the established laws of physics and we don’t need to hear it put so plainly, I don’t know. But anyway, here it is: Everything that lives, dies and everything that’s put together falls apart. Acceptance is mandatory. We do not question why time moves only forward; why we grow older and not younger; and why a once gleaming new truck needs a bit of renovating after a decade or so. We would not expect a broken cup, its pieces lying on the kitchen floor, to suddenly mend and rise to the table from which it fell. A hot kettle will always cool. That’s the way life is. But what lies behind probably the most important of all universal truths? The answer is energy, the controlling factor that gives irreversible life in this world. To appreciate how, you just need to look a little more closely at what you already know to be true.

If I were to ask you to push a small car the length of a perfectly smooth and level track, you would probably succeed, eventually. If I then starved you for a few days and ask you to try again, you would probably collapse with exhaustion before hardly any work was done. You know the reason why: without food your muscles are not able to do work - your body’s engine needs fuel. This is also true of vehicles, of course, the very reason we sometimes end up pushing them; without fuel they don’t work either. But what is the connection between fuel and work, and why do engines and people get hot when they work? The answer again is to be found with energy, and for a description of its importance we have to look to the laws of physics.

The First Law of Thermodynamics states that energy is always conserved; it cannot be created or destroyed. This is true of all systems, large or small. The universe contains a finite amount of energy, energy that is continually transforming from one form to another. Like all stars, the Sun burns fuel and in doing so converts chemical energy to heat and light; plants convert light back to chemical energy. Plants provide the fuel that starts the food chain, a chain of energy that eventually fuels us. The oil that is the remains of ancient, long dead plants provides the chemical energy that fuels most of our machines. And the energy this fuel puts into our vehicles is converted to heat energy and kinetic energy, the energy of motion. When we brake, kinetic energy is exchanged for heat energy, as the vehicle slows.

Energy is the ability to do work, and work is a product of force and distance. This may sound a little complicated until you remember what you would instinctively do if the fuel gauge on your car went into the red and you still had a little way to travel. If you drive fast you will use more fuel. At higher speeds the rolling resistance of tyres, a force that is trying to slow you down, is greater. As is the friction force in all the moving parts between the engine and the road wheels. And, of course, so is air resistance, which greatly increases with increasing speed. All these forces have to be counteracted by the engine, which provides the force to keep you moving. So, you drive more sedately, keeping the engine revolutions to a minimum. For the amount of energy available in the fuel, reducing the force required from the engine allows you to eke out more distance.
Energy not only fuels us and our machines, it is also responsible for giving those that can use it the power to be quick. Power is the rate at which energy is used, and the faster you can use energy the more powerful you will be. Large sports motorcycles are a classic example of how to use energy quickly. With over-square pistons, these high revving, short stroke gas guzzlers do loads of work. With a great power to weight ratio they explode with acceleration and overcome retarding forces to give extremely high speeds. Trucks also use power, but to provide the level of work needed to deal with the high retarding forces caused by their weight. Through higher torque and longer stroke engines, they attempt to limit engine revolutions while maintaining speed. High powered trucks climb hills well.

Because energy gives life, it can also save it. In a collision cars are designed so that energy is converted from that of motion, which is ultimately the killer, to a less harmful form. By collapsing in a controlled way, car structures do work, dispersing kinetic energy. Work is done over a specific distance to reduce the force for a given amount of energy. The reduction in force that results gives life.

When work is done heat is produced, the result of another fundamental law of physics. The Second Law of Thermodynamics says that in any system the energy available to do work is always diminishing. Our bodies and our vehicles only convert a certain amount of the chemical energy in fuel to kinetic energy; the rest goes to heat energy. When we work, we get hot. The Second Law works against us in the efficiency of engines, which will never be allowed to reach 100%. Tyres generate heat that will eventually destroy them; bearings and pistons wear out. It is always the same. If you drop a rubber ball from a certain height it will never bounce back to your hand, not unless you lower the hand to meet it. Internal friction in the ball as it bounces creates heat, so the potential energy given to the ball by the height it was dropped from is never fully regained. A cyclist that free-wheels down a hill will not have sufficient useable energy to climb back up a hill of the same height. They would eventually have to put more energy into the system by pedalling.

And as useable energy diminishes, like a kettle that cools until it is the same temperature as the air that surrounds it, in time everything assumes a position of energy equilibrium, a condition where it is most stable but least able to do work. Materials manufactured from elements in their natural state eventually return to that state. Metals corrode, plastics degrade. Ashes to ashes, dust to dust. Everything dies; it has to, the rules say so.

So, next time you drive your car, think of all the energy changing from one form to another as you travel along. Chemical energy to kinetic energy to heat energy. And think of yourself, how your breakfast is turning the steering wheel and pushing the clutch. All the while both you and the machine are heading in the same direction in space and time, your mechanisms wearing down. When you get home, be sure to plug in the kettle and rest while you can, because summer’s coming and the outside of the house will probably need painting – again.