ABERDEEN PROVING GROUND, Md. -- Armor offers reliable protection against external forces, but what if the enemy is so small that it can take aircraft down from the inside?
Sand and dust can significantly damage helicopter engines, which is why scientists and engineers at the Army Research Laboratory are experimenting with coatings in high-temperature environments with the goal of creating something -- anything -- that will cause sand to slide off the inside of a turbine engine the way an egg slides off a nonstick skillet.
"We are going through a very methodical process to understand the underpinning science and then use the science to predict the materials, what we call the engineered or tailored materials, that will lead to the right solution," explained Dr. Anindya Ghoshal, chief scientist for the laboratory's Vehicle Technology Directorate.
Ghoshal leads the Army's efforts to develop what he calls "sandphobic" coatings. In regions like Southwest Asia, he said, Army forces frequently must contend with brown-out conditions, during which sand particulates and other dust particulates are ingested into the engines.
"Our goal is to have the particles strike the blades or vanes [inside a gas turbine engine] and then flake off," he said. "When we started looking into this problem, we found ... we want to understand the physical, chemical behavior. Once we can do that, then our idea is to take that model and then predict the type of material that would enable us to develop this sandphobic coating."