Nigel Latta crash test
Crashing cars is one of our specialties.
Nigel Latta Blows Stuff Up is a TV show answering tricky, real world, science questions.
The question: Which is safer for you and your family in a head-on collision – an old, heavy station wagon or a modern, lightweight hatchback with a 5-star safety rating?
The only way to find out for real was to create a head-on collision and measure the results. Knowing of our reputation as “experts in full-scale dynamic impact testing” Nigel and the team came to us for help.
As one of the few ISO approved roadside hardware test facilities in the world, we love doing controlled impact tests on cars and trucks. We believe in scientific endeavour and answering unanswered questions, so we jumped at the chance.
We are big believers in prototyping, so we did pilot testing in our laboratory using supermarket shopping trolleys, egg cartons and jelly. The supermarket trolleys simulated the cars, egg cartons were effective crumple zones and jelly moulds represented a passenger’s brain. To account for the difference in mass, weights were added to the ‘station wagon’ trolley, while the egg carton crumple zone was attached to the lighter trolley. The results were stark. Even with the most rudimentary of crumple zones the benefits of energy absorption were clearly evident. Nevertheless, the increased mass of the station-wagon-trolley meant that the lighter trolley still took a significant impact. The concept had been proven – but what would happen on crash day?
We did the full-scale dynamic impact test at our ISO accredited roadside hardware test facility; as one of only six in the world, it was perfect for crashing a 1500kg station wagon into a 1000kg hatchback in a safe, controlled environment. We used a bespoke tow cable configuration to accelerate the cars at the same rate, then release at the right moment to allow the cars to be rolling under their own momentum at the point of collision. To reach the target ANCAP test speed of 65 km/hr, a 4-tonne concrete block was dropped from a height of 24m to accelerate the cars. To record the crash we used 14 cameras at various angles at frame rates up to 5000 frames per second.
The results were spectacular!
The system worked perfectly and the cars impacted head-on. Everyone there agreed they would rather not be in either car. However, on review of the data, high-speed video and inspection of the passenger compartments, we had a clear winner.
The answer: The 5-star safety rated hatchback was clearly the safer place for you and your family.
The benefits of modern safety features such as crumple zones and airbags meant that the accelerations on the occupants were much less severe. Furthermore, unlike the hatchback, the engine of the station wagon intruded on the occupant compartment such that the front seat passengers would have sustained significant leg injuries.
A victory for the pursuit of science, modern cars and clever engineering.
For the full episode and others from the Nigel Latta Blows Stuff Up series, go to //www.tvnz.co.nz/ondemand/nigel-latta-blows-stuff-up.