Avalanche Crash Testing's Fall Guy

Homer, the dummy, has been taking one on the chin—and everywhere else—for you.

Dec 3, 2009
Outside Magazine
Avalanche crash-test dummy

   Photo: Courtesy of age fotostock/iStockphoto

Tell most people you survived an avalanche and they'll at least buy you a beer. Not Robb Larson. "I hear lots of war stories," says Larson, a professor of mechanical engineering at Montana State University, in Bozeman. "But they don't have much useful data. I'm more curious about what exactly happens to a human body in an avalanche. Is it like being hit by a Mack truck or a speeding moped?"

For Larson, these aren't just idle questions; they're hypotheses. To test them, he bought a 200-pound crash-test dummy, named him Homer, and outfitted him with load- and force-measurement devices. When a big storm hits Bozeman, Larson places Homer in a slide path at Bridger Bowl Ski Area just before patrollers trigger an avalanche. Homer gets swept away, and Larson fishes him out and returns to the lab to diagnose his digital aches and pains.

Larson is still analyzing two winters' worth of results and hopes his findings will lead to the development of safety equipment, such as helmet skirts and neck collars to help prevent spinal injuries. For his part, Homer is a cooperative test subject. "He doesn't complain much," says Larsen.

1. THE MIKE-TYSONATER: Two accelerometers register directional forces on the brain. Blunt-force trauma to the head occurs in 20 to 30 percent of avalanche fatalities.

2. WHIPLASH-O-METER: A load cell measures twisting, bending, and compressive/tensile force. Although trauma to the head and neck may not actually cause death, it can slow victims down and prevent those partially buried from self-rescuing.

3. THE BIG SQUEEZE: Asphyxiation is the main cause of death in the overwhelming majority of avalanche accidents. Sensors in the chest will estimate the constriction of airflow.

4. THE LEG BREAKER: Load cells in four areas of the knee and ankle measure twisting and bending along the bone axis and rotation around three axes. Long bone fractures are common among avalanche victims.