"Transonic wind tunnels." . . "Sulfur hexafluoride." . . "Automatic control." . . "Wind tunnel tests." . . . . . . . . . . . "Performance of the 0.3-meter transonic cryogenic tunnel with air, nitrogen, and sulfer hexafluoride media under closed loop automatic control"@en . . . . . . . . . . . . . . . . . "Performance tests." . . "Feedback control." . . "Liquid nitrogen." . . "Mach number." . .