In an airplane, the human proprioceptive system gets easily confused. A 1-g turn could set the plane perpendicular to the ground but still feel like straight and level flight. On a clear day, visual cues let the pilot's brain correct for errors. But in the dark, a pilot who misreads the plane's instruments can end up in a death spiral. Between 1990 and 2004, 11 percent of US Air Force crashes — and almost a quarter of crashes at night — resulted from spatial disorientation.
TSAS technology might fix that problem. At the University of Iowa's Operator Performance Laboratory, actually a hangar at a little airfield in Iowa City, director Tom Schnell showed me the next-generation garment, the Spatial Orientation Enhancement System.
First we set a baseline. Schnell sat me down in front of OPL's elaborate flight simulator and had me fly a m4a4 skins couple of missions over some virtual mountains, trying to follow a "path" in the sky. I was awful — I kept oversteering. Eventually, I hit a mountain.
Then he brought out his SOES, a mesh of hard-shell plastic, elastic, and Velcro that fit over my arms and torso, strung with vibrating elements called tactile stimulators, or tactors. "The legs aren't working," Schnell said, "but they never helped much anyway."
Flight became intuitive. When the plane tilted to the right, my right wrist started to vibrate — then the elbow, and then the shoulder as the bank sharpened. It was like my arm was getting deeper and deeper into something. To level off, I just moved the joystick until the buzzing stopped. I closed my eyes so I could ignore the screen.
