On Sept. 13, 1944, researchers subjected a Bell P-39L Airacobra to frigid temperatures and a freezing water spray in the National Advisory Committee for Aeronautics (NACA)’s new Icing Research Tunnel (IRT) to study inflight ice buildup. Since that first run at the Aircraft Engine Research Laboratory (now NASA’s Glenn Research Center) in Cleveland, the facility has operated on a regular basis for 80 years and remains the oldest and one of the largest icing tunnels in the world.