From the August 2018 issue
You’ve probably heard of the infamous Swedish “moose test,” an evasive maneuver that can produce disastrous, YouTube-worthy results in certain high-riding vehicles. But there’s another moose test, one conducted by Volvo to improve the real-world safety of those vehicles whose drivers aren’t lucky enough to avoid an ungulate impact. This one uses a 790-pound moose surrogate made from a stack of 114 rubber discs, which mimic the density of a moose and are strung together with steel parts and wire. When struck by a Volvo traveling between 43 and 56 mph, this pseudo-moose will hit the windshield first, then roll up and over the roof in a fraction of a second, annihilating everything it touches along the way. This moose test is destructive by design, explains Lotta Jakobsson, senior technical leader at Volvo’s Safety Center in Gothenburg, Sweden, who might just be the world’s foremost expert on what happens in the milliseconds after a car hits a moose. She’s one of few such large-animal-strike experts in the world, helping Volvo perform its dedicated animal-strike tests; it’s quite possibly the only car company to do so. No surprise then that moose dummies are rarer than Volvos in Beirut.
Jakobsson says that, to her knowledge, there are only two such dummies in the world. The other is also in Sweden, at VTI, an independent testing firm. According to a 2015 paper she co-authored, no standardized test method exists to drive the development of occupant protection in crashes with large animals. Yet according to the same paper, the population of large wild animals in Sweden is so high that when traveling at highway speed, drivers pass within about 1000 feet of one every 23 seconds. So there’s good reason to want to know what happens in the unfortunate instance that your vehicle has a territorial dispute with Bullwinkle.
Volvo began moose-strike testing in the 1980s by running one of its cars into a woolly cadaver, a no doubt messy endeavor that led to the development of the surrogates used today. The first-generation dummy comprised bundles of wire and the second contained hoses filled with water, which eventually led to the modern rubber-disc dummy in 2001.
Large animals such as moose represent a special-and potentially deadly-challenge because of their height and high centers of mass. When a passenger car collides with one, it takes out the animal’s legs and introduces its body and/or antlers to the car’s greenhouse; the car’s glass, A-pillars, and windshield header absorb the brunt of the force. Volvo designs those pieces as a system that protects occupants, according to Jakobsson. Most serious injuries in moose-car collisions are due to the collapsing roof and A-pillars or contact with the body of the animal itself, a problem that exists almost exclusively in this type of accident. Also, because deceleration in these events is relatively mild, a car’s airbags usually do not deploy.
Moose-impact testing between successive generations of Volvos (1999–2006 S80s versus 2007–2015 V70s) showed a 36 percent reduction in deformation of the windshield header at the vehicle centerline, which is a big improvement when it comes to protecting front-seat occupants.