Wind Tunnel Testing with a Vertical Stabilizer Common Research Model in Ground Icing Conditions

As part of a larger research program on behalf of Transport Canada and the Federal Aviation Administration, APS Aviation Inc. conducted a series of representative scaled tests in the National Research Council Canada 3 m × 6 m Icing Wind Tunnel evaluating contaminated fluid flow-off from a common research model vertical stabilizer. The goal of this work is to help understand the impact of de/anti-icing fluids with and without precipitation on the performance of vertical surfaces, using existing allowance times that were developed for horizontal surfaces to guide the test exposure times. The data include a qualitative analysis of the appearance of the surfaces and a quantitative evaluation using aerodynamic data from an external balance and manual measurements of the fluid thicknesses on the model surface. The model was evaluated in a clean and dry configuration to establish the baseline aerodynamic performance, with sandpaper roughness testing used to as a substitute for fluids in order to investigate model performance in a static manner. Tests with de/anti- fluids and precipitation, including snow, ice pellets, and freezing rain, were conducted in both static and dynamic takeoff simulations to determine the impact of the fluids and precipitation on the model performance. In general, fluid, fluid and contamination, and roughness testing all had comparable side force losses; however, the worst-case conditions may not have been explored yet as testing was generally limited to warmer temperatures above −10°C. As a proof-of-concept, laser scanning of the model with ice contamination was successfully completed for both pre- and post-simulated takeoff conditions.