Car crash investigation

30th Oct 2014 11:07 am

Nikhil Bhatia joins the team at JP Research to understand how they investigate accidents and how their findings can make our roads safer.

Here’s a chilling statistic. On an average, 15 people lose their lives on Indian roads every hour. India, if you didn’t already know, has the worst road safety record in the world. The unfortunate thing is that this loss of life, and accidents in general, are largely, if not entirely, preventable. But to know how to prevent accidents, we need a better understanding of why accidents happen in the first place. And that’s where JP Research comes in. To give you a brief, JP Research is an independent crash investigation organisation involved in first-hand data collection and scientific analysis of accidents. It’s been operating in India since 2006 with an aim to understand the human, vehicle and infrastructure causes of accidents, and the injuries arising thereof. To date, the firm has investigated over 3,000 cases out of its centres at Coimbatore, Pune and Ahmedabad. Studying the mangled metal, the shattered glass and the broken barriers at accident sights is where each case begins. And it’s no easy job.

On-site

We’ve just reached the site of a horrific crash that occurred a few hours ago on the Mumbai-Pune Expressway. All I can see is a heap of twisted metal that’s lying beside a flyover support pillar. The car is so badly deformed, it’s unidentifiable as a Maruti Wagon R. It’s a disturbing sight made worse when I learn the accident claimed all five of the car’s occupants. While I gather my thoughts, the JP Research team is busy unloading their investigation paraphernalia from the back of the support Innova. I’m told, it’s critical to make preliminary observations and make note of volatile evidence such as skid marks, at the earliest. What makes this particular case harder still is that there are no eyewitnesses whose accounts could have served as a starting block. However, police notes help establish the car’s final position of rest before it was moved by the crew of the emergency services in their attempt to rescue the passengers. For the record, JP Research’s team only takes access once the emergency services have left the scene. 

A walk around the car gives the team its first clues as to what could have happened. The way the roof and right-side A, B, C and D-pillars have folded inwards above the belt line suggest the car was tilted on two wheels at the time of impact with the support pillar. This means, it’s possible the driver had lost control of the car. A thorough analysis of the scene substantiates this possibility. Tyre marks help detail the car’s path from the main expressway, onto the shoulder, then the grass-covered run-off area and finally, to the point at which it halted. 

The team reckons that a patch of water just before the point at which the car seemingly lost control could be the culprit here. At the moment, aquaplaning seems to be the most probable cause of the accident. I use the term ‘most probable’ here because the team does not want to decisively conclude that it was the cause. Only a full-scale investigation can reveal that. Which is why the team is taking all sorts of photographs and measurements at the scene. The distance from the supposed point of aquaplaning to that of impact is of particular interest. The damaged car’s wheelbase, front track, rear track, length of overhangs, tyre pressures and tread depth are other details that make it to the researcher’s initial deformation sketch. They also measure the intrusion into the passenger cell, and make a note of how the occupants could have moved about in the car to ascertain causes of injury. Meticulousness is a key requirement for the job of data collection. Every little bit of evidence is a crucial piece necessary to solve the larger jigsaw puzzle.

Research and analysis wing

Once an accident scene has been studied, measurements taken and interviews recorded, the next step of the investigation begins, where the researchers validate the evidence gathered. Data from the accident site forms the primary basis of the investigation whereas eyewitness and involved parties’ accounts are treated as supplementary. That’s because the fear of being held responsible for an accident may typically lead guilty drivers to provide distorted views of events. With the basic outline established, the team prepares a graphical reconstruction of each case. This is an essential step as it helps simulate what could have happened, understand evasive manoeuvres taken and calculate important numbers. The numbers being travel speed, impact speed, change in velocity, and equivalent energy speed (the speed needed to generate energy of equivalent impact with a rigid barrier). In a nutshell, the greater these values, the higher the severity of accident and injury. 

Once the reconstruction is ready, the next major step for the researchers is to study the injury reports of those involved in the crash. The reports help correlate specific injuries sustained by the occupants to the damage seen within the car. You’d be shocked to know how many injuries and deaths can be prevented by simply buckling up. 

How is the data used? 

With all aspects of a case understood, the team feeds all the variables (over 450 in all) into a database called RASSI, short for Road Accident Sampling System – India. The purpose of the database is to work out statistical trends of the causes of accidents, on the basis of which JP Research, in its annual report, suggests corrective and actionable measures that could help mitigate accidents. Suggestions to concerned authorities range from providing impact absorbing guard rails to something as simple as better road markings. The report also serves to inform manufacturers of India-specific features that can make a big difference in enhancing safety. There are plenty of learnings in the reports (available in the public domain) for individuals too. 

So, wear those seatbelts and helmets, drive in the correct lane and follow all traffic rules. As the statistics support, that’s the safest way to be. 

Here are some of JP Research’s findings on safety on the Mumbai-Pune expressway. (http://www.autocarindia.com/auto-news/mumbai-pune-expressway-study-reveals-startling-safety-statistics-383967.aspx)

 

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