Lessons from a
BURN-OUT

That there was trouble ahead was obvious. A dark spiral of black smoke was rising from the direction of the N3 just short of the Hidcote off-ramp on the Johannesburg side of Mooi River. On arrival at the scene, FleetWatch editor Patrick O'Leary was greeted by a sight that was both awesome - and tragic. In this article, FleetWatch attempts to establish the cause of the fire and to impart some lessons that may prevent similar incidents.

From racing drivers to the man-in-the-street, everyone dreads being trapped in a vehicle fire. While Hollywood continues to thrill audiences with dramatic scenes of fiery vehicles blowing up, the tragic reality of the horror that can result is better depicted off the big screen by people like former Formula 1 racing driver, Niki Lauder, who bear the marks of being trapped in a burning car.

It is this combination of Hollywood flair and real life drama that injects an electric atmosphere into any scene involving a vehicle fire. It is intense. It is awesome and it was such an atmosphere that I came across while travelling back with my family over the Easter weekend from the south coast of KwaZulu Natal. We had diverted off the N3 into Mooi River for my wife to buy some linen and continued along the R103 to the Hidcote offramp. It was while driving off the R103 towards the N3 that we saw the smoke.

Pulling into the emergency lane of the north bound N3, I rushed across with my camera, bashed through the middle bushes and got there in time to see flames bellowing from the rear trailer tyres of an Earlybird Farm semi-trailer. It was seconds before the fire brigade doused the flames leaving the reefer enveloped in a cloud of white smoke.

From a photo-journalism point of view, it was jackpot. From a truck lovers point of view, it was awful. Such a beautiful rig does not deserve such a tragic death. Thankfully the driver was safe having handled the situation most admirably (see sidebar story).

How did it happen?
The accompanying photographs tell the story at the scene but what we're interested in is, what happened and how can such an incident be avoided in the future?

Firstly, it is important to note that the Earlybird Farm fleet is reputed to be well maintained and professionally run. In addition, company drivers are well trained and responsible. Based on this, it would seem the fire was not caused by neglect of maintenance procedures or driver fault. So what was it then.

Let's hear from the driver who I spoke to at the scene. His name is William Machaka, a middle aged man who has been driving for the company since 1996 and who, according to Arnold Prinsloo, human resource and logistics manager of Earlybird Farm, has attended regular training courses including special courses on tyre care and maintenance. His story is a bit vague in terms of detail but it gives some idea of the happenings.

"I felt the truck tractor wasn't pulling nicely so I stopped to check what was wrong. I checked the tyres on the tractor and they were fine but when I got to the trailer tyres, I saw they were very hot and I saw a red glow (Ed's note: not sure what was 'red'). I then immediately phoned the emergency number 10111 and asked for a fire engine to be sent as I knew there was the danger of a fire starting. I then went to the front and unhooked the tractor to drive it forward so that it would be safe."

Sometime between noticing the 'red glow' and driving the tractor forward, the tyres caught alight. It wasn't long after, however, that the fire brigade was on the scene. The pity was that the first tender to arrive didn't work. A second arrived soon after and that's the one in the photographs seen dousing the fire.

According to Prinsloo, to whom FleetWatch spoke the next day, the C-Track fleet management report on the vehicle's movements showed that over the former three days and up to the incident, there had been no harsh braking nor excessive speed. The average speed was around the 80kph mark for the three days driving.

Based on all this, it would seem that all normal procedures of maintenance and correct driving were adhered to. So what was the cause?

FleetWatch spoke to two people for their opinions. The first was Jack Webster and the second, Patrick Swan, an accident reconstruction expert. It must be pointed out that Jack Webster's analysis is based on what he was told whereas Swan's was based on actual examination of the rig and components. Both are pertinent as lessons to be learnt and therefore both are given here. Firstly, let's hear Webster's theory

First opinion
"Based on the information given by the driver that while travelling along the N3 freeway at a speed of around 75 km/h, he felt what he thought to be a loss of power of the truck-tractor the following assumption can be made with a high degree of probability.

"The standard braking system of heavy vehicles in South Africa (and adopted internationally) is the twin-line air system in which:

• Two air lines connect the drawing vehicle air system to the air system of the trailer.

• The line (usually coded red) carries a continuous supply of air at full pressure from the drawing vehicle to the air reservoir via a relay valve on the trailer. This line is referred to as the emergency line.

• The second line (usually coded yellow) connects the brake foot pedal valve on the drawing vehicle to the relay valve on the trailer. Under normal operating there is no air in this line which is called the service line.

"The function of the system is as follows:

• When the driver applies the foot brake pedal, air pressure is released into the service line and the relay valve causes the air in the air reservoir to be released to the brake chambers (diaphragms) on the axles - and the brakes are applied.

• The air pressure in the emergency line keeps the air in the trailer reservoir up to pressure and also keeps the brakes in the "off" position.

• Should there be a drop in pressure in the emergency line, the emergency function of the system comes into play and the trailer brakes will be applied.

"It is reasonable to assume that this could well have been the cause of the incident here. If the semi-trailer brakes came on as a result of an air leak in the emergency line, the brakes would bind and heat would be generated, which would be transferred to the wheel rims and then to the tyres.

"It is for this reason that thought is given to considering a drop in pressure in the emergency line between the truck-tractor and the semi-trailer.

"Also, during discussions at the IRTE Technical Committee on the subject of air brake couplings, it was agreed that although these couplings are covered by SABS Specification SABS 1477 which is unfortunately a voluntary specification, it is being recommended that this specification be made a compulsory motor vehicle specification. This would ensure compliance, not only on new but also on vehicles in service by inclusion in SABS 047, the Code of Practice for the testing of motor vehicles for roadworthiness.

It is of interest to note that during the IRTE discussions about brake line couplings, it was reported that there have been a number of cases of semi-trailer tyres being set on fire by the heat from the brakes binding as a result of leaks in the emergency air brake line due to faulty couplings."

Second Opinion
FleetWatch then spoke to Patrick Swan after he had examined the rig. His conclusion was that one of the trailer tyres either ran flat via a fast puncture or had a blow-out.

"If brake binding had occurred, the brake linings would have been glazed or shown some signs of abnormal wear but this was not the case. They were fine. Another possible cause of such an incident is wheel bearing failure but in this case, I ruled that out as the bearings were also fine.

"Also, if brake binding had occurred, passing motorists would have noticed smoke rising from the wheels and alerted the driver. However, according to the driver, no-one alerted him to any potential problem. He merely felt the truck tractor lacking pulling power.

"Taking all this into account, I put the probable cause down to a fast puncture or a blow out. The ignition temperature of a tyre is 200 0C and given the tremendous rolling resistance of a punctured tyre, this temperature can be quickly reached resulting in a fire."

So what can be learnt from all this and let me quickly reassure Earlybird Farm that in pointing out these lessons, we are not implying that the company does not carry out such practices. We're merely using this incident to spur a few thoughts around preventing similar incidents occurring.

No substitute for maintenance
Firstly, there is no substitute for correctly maintaining your rigs. When it comes to an insurance claim on an incident such as this, there is not an insurance company or broker around who would be able to reject the claim based on maintenance neglect. And that is reassuring for Prinsloo who is facing a hefty bill.

"We were lucky in that the fridge unit was undamaged so that saves us a lot. However, the inside was badly damaged and the main beam of the chassis was bent from the heat. The load was also totally lost so the initial estimate of loss is around R400 000. We are also self insured to the point where we have to pay the first R250 000 of any claim so it's a costly incident for us."

And herein lies another lesson. As is well known, most operators have opted for either partial or total self insurance so let this incident also act as the spur for you to revisit those policies and check they are suitable to your operations. You can stick to best practice in terms of maintenance, driver training and other operational issues but as this incident proves, accidents can still happen due to the nature of the game. Check that your insurance cover is correct for your circumstances.

And for goodness sake, if you do go the self insurance route, don't be tempted to rifle that till. You could just be caught very short when you need those funds and you've used them elsewhere. Get a reputable broker to advise you when going this route. It's not as simple as it's often made out to be.

Establish policy procedures
Jack Webster's hypothesis on air leaks is a real one and the lesson here is to regularly check the braking system for leaks. This is a safety critical item and should be given the strongest attention. FleetWatch technical correspondent Dave Scott constantly advocates for the setting up of policy procedures. Ensure you have such a policy in place for brake checks.

The third lesson here is to have a tyre check policy in place - both within the depot before a rig pulls out and on the road. And let's face it, even with such a policy in place, misfortune can still strike - as this incident proves.

A fast puncture picked up on the road - as per Swan's conclusion on this incident - is not the operator's fault. Many readers will recall the interview carried in the September 2000 issue of FleetWatch where IDC's Peter Burkhalter pointed out that his rigs had picked up 869 punctures in the first seven months of the year from nuts, bolts, nails and other items strewn on the roads. His conclusion was that a lack of maintenance was causing rigs to fall apart and the good guys were collecting the 'fall-out' in their tyres.

Given this, it would seem to me that a good investment would be some form of monitor in the cab which alerts a driver to the fact that he has a puncture - slow or fast. If Swan's conclusion is correct, the driver would immediately have been alerted by such a monitor rather than by noticing a fall off in the pulling performance of the tractor. This may have caused him to stop before that critical 200 0C tyre ignition point was reached. It's just a thought and a relevant one given the fact that many drivers may not be as alert as this driver was to the handling and performance of his rig.

Train and keep training
A final lesson is that, just as there can be no substitute for professional maintenance, so too can there be no substitute for professional driver training. Earlybird Farm uses the services of Masterdrive for regular and on-going driver training. This company is headed by Dave Johnston, a man who has been involved in driver training all his life and has a true passion for training. He is also a man who gets extremely angry at what he sees at misdirected efforts and funds by the government and other parties in trying to reduce South Africa's road carnage.

To Earlybird Farms and particularly to Arnold Prinsloo we say: Sorry about your loss. It always pains us when we see a rig in an accident or incident. But congrats on the approach you take to your fleet and particularly your driver training.

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