Downwash Investigation of Horizontal Tail Plane Configuration for 19-Passenger Aircraft Based on a Wind Tunnel Test

An investigation has been conducted on wind tunnel test data of 19-passenger aircraft to see the phenomena of the downwash effect.The objective of this investigation is to analyze the downwash effect on the variation of horizontal tailplane configuration that is installed on the vertical tailplane of the aircraft and on the variation of flap configuration.Each flap configuration represents the condition at the flight profile of cruise, takeoff, and landing.The horizontal tailplane configuration is varied by changing the angle of incidence and the vertical position on the vertical tailplane.Analytic calculation was conducted on wind tunnel result data to quantify the downwash effect.A computational fluid dynamic simulation is performed to obtain the visualization of the downwash effect and for wind tunnel data verification.From the investigation, it is found that the lower position of the horizontal tail has a smaller amount of downwash than other positions.The flap configurations have greatly affected the perceived amount of downwash.The greater deflection of the flap generated downwash even more.