Oct

Crash analysis – stripping down chaos

2014-10-31 15:26
Fearless in seeking the truth through hard facts, Craig Proctor, CEO of Accident Specialist, leads the way in tackling the chaos that flows from complex accident scenes.

“Take charge of crash information to prevent serious fall-out losses.” That’s the clear message that Dave Scott, FleetWatch technical correspondent, brings to transporters after attending an annual two-day intervention for law-makers, local authorities, law enforcement and companies interested in fleet crash control.  The event is run by Craig Proctor-Parker, CEO of Accident Specialist – his Durban-based company that conducts specialised crash investigations. The first day was used for looking at the latest trends in technology and crash investigation. The second day was a real, shattering, on-site crash experience where actual crashes are created and analysed. It was all an eye-opener. Read on…

Terminology has changed. An accident is something that cannot be reasonably foreseen or predicted and cannot be avoided. It just happens. “A crash, on the other hand,” says Brandon Hughes, Traffic Safety Resource Prosecutor in Alabama USA, “is the result of choices made and risks disregarded. Crash is a word that evokes a violent image and shouts blame. After all, crashes don’t just happen, do they? Somebody is always at fault in a crash. But what about accidents? Nobody’s fault? Just an unfortunate event? Simply in the wrong place at the wrong time? Does it really matter?”

Whatever way one views a ‘crash’ – the new term for ‘accident’ – it’s a chaotic event that very few ever prepare for. And where do where truck drivers get procedure training to limit the fall-out following crash chaos?

Lack of accurate stats – a rotten drag on SA road safety

Speaking at the event, Luchas Steenkamp, training manager at TüV Rheinland, made the point that South African road safety is in dire straits. “South Africa is collecting crash data at such a low level that it cannot be used for effective countermeasures,” he said.

If you try to miss the pole, you will roll. A glancing low speed (50km/h) crash with a pole rolled this car.

If you try to miss the pole, you will roll. A glancing low speed (50km/h) crash with a pole rolled this car.

This is in spite of the fact that, as Steenkamp says: “Crash investigation has undergone dramatic change from a camera and tape measure to science engineering. Crashes no longer initiate a criminal hunt but involve civil, insurance and environmental actions as well.”

According to Steenkamp, South Africa desperately needs validated crash research information to focus on priorities. “There are limited resources so let’s not waste effort and budget. Crash information will allow for selective law enforcement – a focus on high-risk drivers in high-risk areas.”

Steenkamp outlines five levels of crash investigation:

  1. Reporting – the low-level Accident Report (AR) in use with SA Police – is not even accurately filled in.
  2. ‘At crash scene’ investigation.
  3. Technical investigation – this involves delayed data collection.
  4. Crash reconstruction.
  5. Cause analysis.
The explosive effect of a major crash scatters debris – some big pieces, such as this complete dual wheel set still mounted on the axle stub. Other road users beware!

The explosive effect of a major crash scatters debris – some big pieces, such as this complete dual wheel set still mounted on the axle stub. Other road users beware!

KwaZulu Natal’s eThekwini Municipality has alarming 2013 figures to offer. An average of 174 crashes resulting in 1,35 fatalities, 6,2 serious injuries and 9,1 slight injuries occur every day. Included in the average are peak crash periods following bad weather that can top 350 crashes in a single, hectically rainy day! Multiply these figures across the face of South African urban centres and you will get a frightening, cumulative daily result.

To pin a Rand value on these stats, eThekwini Municipality uses the original CSIR costs, inflated by 10% each year. They are R1 467 721 for a fatal crash (in 2014), R385 244 for a serious crash, R109 684 for a slight injury crash and R70 497 for a damage-only crash.

It  is figures such as these that prompt Steenkamp to say: “We must urgently move towards an effective road safety system that does not just rely on inaccurate and simple AR reports. We need the information behind crashes – not accidents – and get into understanding (not only reporting) as well as research (not just policing).”

In-vehicle digital video recording – DVR – much more than pictures

A DVR only needs three satellites to locate its position to within 3m – four satellites will track for height as well. And there are up to 32 satellites triangulating DVR positions at any one stage where GPS is not weather or day/night dependent.

Despite an under-run bumper on the trailer, the impact still smashed off the dual wheel and axle at 100km/h.

Despite an under-run bumper on the trailer, the impact still smashed off the dual wheel and axle at 100km/h.

DVR looks at the road ahead outside the cab only from a 140-degree driver viewpoint. It can also registers both inside the cab at a 130 degree angle while simultaneously recording outside the cab. A 16-Gigabyte SD card will provide up to four hours of infinite/continuous recording.

Modern DVR units include an accelerometer – the technology behind this is Micro-Electro-Mechanical-Systems (MEMS) – measuring all sudden movements shaking the camera on the Y, X and Z axis, up and down, forward and reverse, plus side to side. Accelerometer G-force sensitivity can be set and data gets stored on an Event Data Recorder (EDR) that is both date and time imprinted for retrieval.

And pictures explain a thousand words. Weather conditions relative to speed, traffic and road conditions as well as driver and crew behavior, are all recorded against events on the EDR. In one example shown, one could clearly see the driver was smoking a ‘zol’ – a large, hand-rolled dagga joint – which continued for hours prior to crashing by which time the driver had reached a stage of ‘two eyes peering out of one socket’! In the same crash, driver and crew were clearly not wearing seatbelts.

The 140 degree forward view can also be used for calculating the speed of oncoming vehicles. The distance between physical reference points can be measured and with the DVR time lapse occurring between the visually-recorded reference points, actual speed can be determined.

It’s fractions of a second

In calculating the speed of an oncoming vehicle from a DVR recording, CEO of Forensic Road Crash Investigation Services, Wilna Badenhorst, demonstrated that it only took 0,25 seconds for a vehicle to cross over the double white line in the centre of the road prior to collision. Badenhorst uses a standard benchmark driver reaction time of 1,6 seconds to perform the following:

  • Hazard perception
  • Identify the hazard
  • Decision making
  • Execution

To the 1,6 seconds can be added any number of seconds (dagga maybe?) that will drag on these processes to lengthen reaction time. Where a driver has to turn his eyes towards a hazardous situation, eye movement alone costs 0,4 seconds. And if the vehicle reacts slowly to executing the decision, many more lost seconds can be added.

Real-life remote-control crash tests – explosive!

The trailer under-run guard gets imbedded into the car. without the under-run guard, this trailer would take off the car’s roof and the heads of all the car’s occupants.

The trailer under-run guard gets imbedded into the car. without the under-run guard, this trailer would take off the car’s roof and the heads of all the car’s occupants.

Proctor-Parker and the team from Accident Specialist must be congratulated. It is no mean feat to organise the crashing of three cars – at speed and two by remote control – in real time and all safely in front of a horrified audience.

The first crash was a Ford Falcon car at 98km/h which smashed into the right-side rear end of a stationary, double-axle flat-deck trailer. The impact was explosive! It’s a sobering and shattering experience. The stub axle holding one duel-set of trailer tyres was snapped off and thrown into the opposite lane to demonstrate that such crashes can have serious knock-on consequences for other traffic.

The second crash involved a Mercedes-Benz 230 sedan travelling at 55 km/h which had a glancing head-on with a Tata Indica.

The final test was a Nissan Sentra which was crashed into a stationary wooden pole at 50km/h. Even at this low speed, the pole snapped and the car rolled.

Trace the chaos

Crashes were conducted in ideal conditions on a straight hard surface. Poor weather and road conditions can change the whole crash outcome and complicate the investigation.

Crashes were conducted in ideal conditions on a straight hard surface. Poor weather and road conditions can change the whole crash outcome and complicate the investigation.

Crash chaos means that the observable final position of damaged vehicles needs to be traced back to where the crash actually occurred. Establishing the truth has to be drawn from multiple sources – tracking systems, in-cab DVR, engine ECM, crash debris positions, weather and light conditions impacting visibility, road surface and curves, road marking, vehicle instrument clusters, vehicle fluid dispersal and live witness accounts, to name but a few inputs.

Any crash involves big money – a fatality results in an average cost of R1,4 million. The result is that people become mean and untruthful. And that’s why specialists like Craig Proctor-Parker and Wilna Badenhorst will always be busy establishing the truth.

There are also other serious impacts. We are too busy counting body-bags and overlook the serious damage that every crash makes on our environment – the spill – as well as on the energy consumed in repairs, hospital beds occupied and injured people whose lives will never be the same.

Drivers must be trained in procedure that follows any crash. For example, how many are aware that the warning triangle, indicating hazard and problem, must be placed a minimum of 45m ahead of the obstruction (Regulation 214)? And even if drivers know this, what is 45m?

Finally, the crash tests also demonstrated why rear-seated passengers must wear seat-belts. A car stopping at 100kmh will see the rear passengers continuing at that speed and wiping out the driver and themselves. Everyone must buckle up!

References

http://www.alabamaduiprosecution.com/resources/The-Crash-Course/Word_Choice_Matters.pdf

SAE – Bosch Automotive Handbook 7th Edition – page 438

Crash statistical data provided by the eThekwini Transport Authority


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