Avalanches for dummies
by Andrea Clark Mason
Extreme-sports guinea pig
A man leans on a bamboo pole high above the slopes at Bridger Bowl near Bozeman, Mont. From a distance, he appears remarkably calm, even as ski patrollers throw explosives onto the snow-loaded slope directly above him. There's a loud blast and a fracture forms in the snowpack, releasing an avalanche that engulfs him in a wall of powder. When his turbulent 50-meter ride down the mountain ends, all that's visible is his turquoise sleeve, poking up from the snow. Everyone knows that avalanches can be deadly. This guy is different from most other victims, though: He always survives.
His name is Homer, and he's a certified crash-test dummy purchased in 2006 by Montana State University's mechanical engineering department. During the past two winters, professor Robb Larson and his mostly undergraduate engineering students have periodically hauled their 5-foot-10-inch, 190-pound plastic colleague into danger in hopes of learning what exactly happens to a human body inside an avalanche.
Homer is dressed for the occasion in an old North Face jacket and hand-me-down black pants. Before the slide, the researchers set up a video camera at a safe distance and use a remote control to activate sensors on the dummy's head, femur, knee and ankle. When the slide hits him, the sensors measure its pressure and note how it rotates and bends his body. The data is transmitted to a thumb drive in Homer's backpack. When it's over, Larson's rescue team zeros in on signals from Homer's avalanche transceiver to locate and dig out the powder-covered victim. Then everyone returns to the lab to find out how Homer is doing.
Larson is still interpreting the data, and he says a lot more testing needs to be done. So far, however, Homer has reported enough bending and twisting to cause sprains and possible broken bones or dislocated joints.
Larson plans to eventually compare his findings to medical databases from automotive crash tests and cadavers to see what the sensors' data might translate to in a living person. A concussion? A torn ACL? "What really matters to most people," Larson says, "is 'Will it kill me?' "
Larson hopes his work will be useful in developing better recovery methods and safety equipment -- more effective helmets, for example. And Homer himself could be used to test helmet skirts or neck collars. (Many avalanche victims die from trauma to the neck or head.) Some companies have also expressed interest in using Homer to test avalanche airbags, which inflate to keep a victim near the surface of a slide. Could riding the top of an avalanche actually expose a victim to more injuries than being buried in the deeper, slower moving part, if the slide passes through obstacles like cliffs and trees? In order to find out, Larson says, Homer would have to be fitted with additional sensors on his neck, torso and arms. But funding for the project is scarce, and Homer himself wasn't cheap; he cost $60,000.
When he's not on the slopes with Homer, Larson serves as director of the Montana Wind Applications Center and assists snow scientist Ed Adams in his new cold lab, studying how snow changes under various conditions.
Although there are plenty of avalanches in the mountains around Bozeman, it's not possible to safely haul Homer directly into the path of one of them. So Homer and his entourage are loyal to the slides at Bridger Bowl. Homer has ridden the chairlift up and been towed on a sled behind a snowmobile. Three downhill skiers once hauled him up the mountain on a sled with the help of a pulley. One particularly strong guy even carried Homer over his shoulder, like a sack of potatoes.
"No wonder nobody's done this before," Larson says. "It's a total pain in the butt."© High Country News