The Boeing V/STOL test facility has been in continuous use since April 1968 and has logged over 80,000 hrs of testing. The tunnel has a large (20 foot x 20 foot), versatile test section useful for testing fixed and rotary wing aircraft models, half models, powered models, non-aeronautical vehicles and structures, and some full-scale vehicles. The fan is 39 feet in diameter and has 9 fixed-pitched wooden blades.