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A Contentious Cultural Change – Speed Limiters

Apr 26, 2018 Trucks, Trucking, Dave Scott, fleet, commercial vehicles, speed limiters, driving,



Dave Scott

Under Regulation 215, speed limiting devices were mandated for fitment on trucks, mini-buses, midi-buses and buses from 1 Dec 2016. Regulation 293 deals with actual vehicle classes and speed limits.


The speed limit for trucks over 9,000kg gross vehicle mass (GVM) and gross combination mass (GCM) has always been 80kph but this has never been physically governed by a speed limiting device. Adhering to 80kph has been in the hands of a driver who can temporarily overspeed to deal with a situation that demands more acceleration, or where extra speed at the foot of an incline allows the vehicle to ascend the gradient in a higher gear.


Now enter speed limiters that remove a driver’s decision for top vehicle speed and it becomes a contentious issue


Perception rules the day

Attitude to speed in trucking circles has developed over many years where perception and habit play a major-role in driver attitudes. Trucking is all about payload, speed, distance and time where time plays a leading role perception. Most drivers think ‘the faster you go the shorter the trip’. The minibus taxi industry is a prime example of driving on road-shoulders or jack-rabbiting between traffic lights with reduced passenger safety and minimal impact on trip-times.

Here is a projection for extra trip time over similar distances for a top speed of 100kph vs 80kph.


The above chart shows a saving of only 15 minutes over 100km using a top speed of 100kph vs 80kph. How is the 15 minutes gained to be used productively when considering the impact of increased fuel consumption and vehicle wear?


The practical problems around speed limiters

Speed limiters remove a driver’s discretionary ability to increase speed over the limit – for a truck over 9t GVM 80kph is the maximum, never mind how the vehicle is geared. This presents variety of situations on the road:

  • Driver frustration – things are not what they were and perceived to be very restrictive
  • Dangerous calls of judgement – a driver may decide to overtake but cannot accelerate in the middle of overtaking if needed. There is no window of opportunity.
  • Driver-hours on the road are a national problem – fatigue and boredom are serious challenges behind the wheel and speed limiters will now stretch drivers to the limit. Operators are not going to employ more drivers just because of speed limiter installations.
  • Drivers now prefer the older trucks – where there’s a choice, drivers are already expressing the desire to drive the older trucks in a fleet that are not equipped with the new limiting devices.
  • The lack of law enforcement at night allows many transport operators, especially courier companies, to travel beyond legal speed limits because of promises to deliver within a set time envelope.

The new speed limiters now introduce an element of endemic corruption – some are prepared to reset the engine software and bridge the gap so that the limiters no longer function. This all compounds a lack of enforcement. The difference between an ‘older’ truck and a newer model lies inside an engine ECU. While there is technology to distinguish between new and old truck models on the road, will traffic officers be trained to use this and enforce the law?


Medium Trucks down to 100kph

Medium trucks – 3,5t to 9t GVM – are now limited in top speed to 100kph. All trucks under 9t GVM previously were allowed a top speed of 120kph. The reduced speed has a significant effect on fuel consumption. Here’s a fuel consumption projection for a 6t GVM medium truck over 1140km on an N3 return trip – a saving of 100 litres fuel for an increased trip time of 4 hours between 120kph and 80kph:


Top Speed

Distance

Time

Fuel used

120kph

1140km

12h10

263,5 ℓ

100kph

1140km

13h39

207,7 ℓ

80kph

1140km

16h12

163,6 ℓ


It is apparent that average speed really counts in this new era of speed limiters. A top speed of 100kph can translate into an average speed of anywhere between 65kph to 80kph depending on the terrain and traffic conditions. Some routes are entrenched in a speed culture – the long haul from Cape Town has been known among truckers as a 90kph route because if you did not want to get ‘queued’ then 90kph was (and still is) the outer parameter to drive to.


Against a background of inadequate and validated road traffic crash statistics, the intention of the speed limiter Regulation is to improve road safety. But we are seeking a cultural change including a change in attitude to speed and time. On top of this the Department of Transport is attempting to use unresearched and un-validated technology to control speed on the road. Will this reduce the more than 830,000 road traffic crashes involving 1,7 million South Africans every year that annually cost the economy R142.95 billion and 3,4% of GDP? (CSIR report)


The attitude towards speed limiter regulation is already a negative one when driver training appears to be the only way out. The annual statistics and individual forensic crash analysis will tell in time.


In the meantime, the truck manufacturers have no option but to comply with regulation 215 (1A).

Reference: Costs of Crashes in South Africa – Research & Development Report August 2016 – Prepared by the CSIR for the Road Traffic Management Corporation


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