Airborne Platform for Ice-Accretion and Coatings Tests with Ultrasonic Readings (PICTUR) 2023-01-1431

Hazardous atmospheric icing conditions occur at sub-zero temperatures when droplets come into contact with aircraft and freeze, degrading aircraft performance and handling, introducing bias into some of the vital measurements needed for aircraft operation (e.g., air speed). Nonetheless, government regulations allow certified aircraft to fly in limited icing environments. The capability of aircraft sensors to identify all hazardous icing environments is limited. To address the current challenges in aircraft icing detection and protection, we present herein a platform designed for in-flight testing of ice protection solutions and icing detection technologies. The recently developed Platform for Ice-accretion and Coatings Tests with Ultrasonic Readings (PICTUR) was evaluated using CFD simulations and installed on the National Research Council Canada (NRC) Convair-580 aircraft that has flown in icing conditions over North East USA, during February 2022. This aircraft is a flying laboratory, equipped with more than 40 sensors providing a comprehensive characterization of the flight environment including measurements of temperature, pressure, wind speed and direction, water droplet size and number distribution, and hydrometeor habits imagery. The flight tests of the platform included assessment of passive icephobic coatings as well as heat-assisted tests. Monitoring tools included visual high resolution, real-time inspection of the surface as well as detection of surface ice using NRC’s Ultrasonic Ice Accretion Sensors (UIAS). In this paper, we present the new platform and show some preliminary commissioning results of PICTUR, collected inflight under, predominantly, supercooled small droplets and supercooled large drops (SLD) icing conditions. The combination of the platform and the complementary sensors on the aircraft demonstrated an effective and unique technique for icing studies in a natural environment.