It’s a contentious issue and one that changes a simple conversation into full blown arguments: speed and speed cameras, safety device or revenue raiser? First up, what EXACTLY is speed? According to Wikipedia: In kinematics, the speed of an object is the magnitude of its velocity (the rate of change of its position); it is thus a scalar quantity. The average speed of an object in an interval of time is the distance travelled by the object divided by the duration of the interval; the instantaneous speed is the limit of the average speed as the duration of the time interval approaches zero. Like velocity, speed has the dimensions of a length divided by a time; the SI unit of speed is the metre per second, but the most usual unit of speed in everyday usage is the kilometre per hour or, in the USA and the UK, miles per hour. For air and marine travel the knot is commonly used.
Or more simply, A cyclist who covers 30 metres in a time of 2 seconds, for example, has a speed of 15 metres per second. Basically velocity over distance in a time frame. In Australia, we measure our speed as kilometres per hour, so fifty kilometres per hour is fifty thousand metres of distance travelled every 3600 seconds. This equates to be 13.888 metres every second. 80 k’s per hour is 22.222 metres per second and 11o is 30.555 metres per second. Ok, we’re clear on that?
There are those that say that if you don’t speed then you won’t receive an infringement. True, undeniably true but it sidesteps what the argument is all about. There’s also the ubiquitous and well worn “speed kills”. Let’s put this into one context: if a driver travels at 60kilometres per hour in a rated zone of fifty kilometres per hour, that driver is, technically, speeding. If the driver is doing the same speed, sixty kmh in an 80 kmh zone, the same speed remember, they’re not speeding. So, according to convention, the media, the police etc, the first is dangerous yet, somehow, that same velocity over distance per time isn’t….back to “speed kills”….which speed, exactly?
Our residential roads are zoned at 50 kmh. Our highways are zoned at either 100 kmh or 110 kmh. Travel at 80 kmh in a 60 kmh and you’re speeding BUT in order to achieve a speed of 100/110 kmh you not only have to reach 80 kmh but EXCEED that speed. So what is dangerous, 80 in a 60 or passing that formerly dangerous speed to one that is deemed safe????
Ok, we’re told that speed kills. It’s a blanket statement, exactly like “the customer is always right”. The problem is the caveat part of those statements is missing. Speed doesn’t kill, it’s the sudden stop. This is where physics comes into play, with an object in motion possessing kinetic energy. That kinetic energy has to be dispersed when that object stops; also, a little more physics. You may have heard of “G force”; from Wikipedia: G-force (with g from gravitational) is a measurement of acceleration felt as weight. It is not a force, but a force per unit mass and can be measured with an accelerometer. Since such a force is perceived as a weight, any g-force can be described as a “weight per unit mass” (see the synonym specific weight). The g-force acceleration acts as a multiplier of weight-like forces for every unit of an object’s mass, and (save for certain electromagnetic force influences) is the cause of an object’s acceleration in relation to free-fall.
Under normal and everyday circumstances, a human is experiencing a G force load of 1G. Deceleration also involves G force and the higher the deceleration the higher the G force. To be slightly technical: The expression “1 g = 9.80665 m/s2“ means that for every second that elapses, velocity changes 9.80665 meters per second (≡35.30394 km/h). This rate of change in velocity can also be denoted as 9.80665 (meter per second) per second, or 9.80665 m/s2. For example: An acceleration of 1 g equates to a rate of change in velocity of approximately 35 kilometres per hour (22 mph) for each second that elapses. Therefore, if an automobile is capable of braking at 1 g and is traveling at 35 kilometres per hour (22 mph) it can brake to a standstill in one second and the driver will experience a deceleration of 1 g. The automobile traveling at three times this speed, 105 km/h (65 mph), can brake to a standstill in three seconds. For humans, death or serious injury occurs with a G force rating of >25G. So, clearly, it’s neither speed (to keep it simple, let’s presume a constant velocity therefore a G force of 1G) nor acceleration (as even the space shuttle was kept to an acceleration G force of less than 3G), that kills people, it IS the sudden stop. To use a somewhat graphic yet famous example, the crash that took the lives of Princess Diana and Dodi Fayed was estimated to have a G force factor of 70G to 100G….
The Bathurst 1000 event over the weekend of 11-13 October 2013 saw a number of crashes, including young drivers Tim Slade and Chaz Mostert. It was estimated that the G force shunts for both was around 30G. Now, here’s the rub; the vehicles they are driving are built and engineered with what is considered high speed in mind. Also, the safety mechanisms we take for granted, primarily airbags, are removed BUT they have super strength seatbelts in a configuration known as a four point harness. Relative movement or slackness of these belts is hugely minimal compared to the seatbelts in cars (http://hyperphysics.phy-astr.gsu.edu/hbase/seatb.html) therefore their bodily movement will be severely reduced. As a result, a combination of that primary safety factor and car construction aided in reducing serious injury, to the point both drivers reported bruising and some aches, but nothing worse.
So speed kills? No, it doesn’t. Clearly, obviously, provably. Therefore the argument for restricting speed limits and using speed cameras has serious opposition. Therefore the argument for speed cameras to stop speeding is invalid. An example: a driver is travelling a road zoned at 110 kilometres per hour in dry conditions and 100 percent visibility (the caveat). It’s raining, it’s foggy and it’s dusk. Visibility, even with headlights on (a safety factor badly overlooked) is 10 metres. Remember that 110kmh is 30 metres PER SECOND. Is it safe to travel at 110 even though that’s what the signs say that driver can do? But if that driver DOES travel at 110 they aren’t breaking the law and therefore not subject to receiving an infringement. But is it SAFE? By no sensible reasoning should this be seen as safe. Road limits are set for the presumption of 100% visibility for the direction of road travel and road design and the surrounding area and in many areas they are too low.
So: speed cameras are used to restrict excessive speed, with posted limits set under what is presumably the best conditions, with one unassailable fact, the biggest chance factor of all: how good is the driver? Anyone that races at Bathurst is there because, not only can they race, they can handle speeds that the authorities would have us believe is dangerous. Remember, the majority of the year sees the track a residential road, with a posted limit of just 60 kmh. If speed kills, then why are all the drivers that raced this year still alive? No, it’s not a petty and frivolous question, as we are told, repeatedly, speed is dangerous…..but to who? Certainly not Mark Winterbottom, certainly not Warren Luff, certainly not Andy Priaulx. Speed cameras are used to control speed, they don’t control bad drivers. Well trained and educated and AWARE drivers are so much more safer to deal with and they can deal with speeds others can’t. There is no justification for speed cameras in many locations but yes, in some places they should be mandatory.
According to the Bureau of Statistics, in 2010, a staggering 44.2% of fatal crashes were a single vehicle crash, whilst 42% were multiple vehicle. The inescapable fact is these crashes have one common cause or factor and it’s not speed. It’s a bad driver. In the same year, at speeds of up to just 60kmh, the equation was 28.3% of fatalities occurred in that grouping, whilst in the sixty five to ninety zone it was 22.4%. What’s more frightening is the change of numbers in the Northern Territory; in 2009 it was 13 people per 100000 that were in a fatal crash. In 2010, it jumped to 21. Those numbers increased almost year by year after the unlimited roads were changed to a maximum of 130 kmh. Time of the crashes is also an important factor: in 2012 there were more fatalities in NSW between 12 and 1 pm (30) than at any other time of the day, with Victoria not far behind at 18 between 1 and 2pm. Neither could hardly to be said it’s peak hour traffic yet Allianz Insurance says the most common form of crash is the nose to tail. Guess when these are likely to happen? That’s right, peak hour.
Speed doesn’t kill. Speed cameras do nothing to reduce the reason people die in a crash: the sudden stop. The Victorian police say they’re going to hide their cameras so the operators don’t get hurt by the occasional twit that’s just been nabbed speeding, presumably because 1) they’re a twit for not slowing when the sign says there’s a camera or 2) didn’t slow because they were too busy looking at their speedometer. It’s commendable but I’m sure you can understand the cynical laughs from those that can do what the law, ostensibly, wants everyone to do. Drive, rather than steer, a vehicle.