When Chris Tuan was a Department of Defense contractor in the early 1990s, the Air Force asked him to think of something that could de-ice its airfields around the world.
Heavy cargo aircraft were landing on icy runways and skidding off, he says, "so they wanted to find out some innovative way to de-ice the runway."
The challenge? He couldn't use any salt or de-icing chemicals because of the damage they can do to concrete.
