The DREAm-TILT project was focused on the assessment of drag reduction achieved through the aerodynamic optimisation of some critical components of the ERICA tiltrotor fuselage. This was accomplished both from an experimental and a numerical point of view.

A CFD-based optimisation activity had been carried out in GRC2, and proper shapes of some fuselage components (i.e. wing/fuselage junction, wing/nacelle junction, nose, landing gear sponson and empennage) had been identified, that contribute to reduce aircraft drag and enhance aerodynamic efficiency.

In DREAm-TILT, the benefits obtained from the aerodynamic optimisation in terms of drag reduction were thoroughly assessed through a dedicated wind tunnel campaign: specifically, the final optimised fuselage were tested and the drag reduction with respect to the original configuration was determined. All the optimised components were tested sequentially with the aim of getting an accurate drag breakdown and identifying the contribution of each component to the overall aerodynamic performance of the fuselage. Additional classical flow visualisation was ran and infrared thermography carried out to enhance knowledge on the transition and separation regions for the different drag reduction configurations.

Moreover, a CFD activity was carried out on both the model scaled and the full-scale aircraft in order to evaluate rotor effects and the full scale (Mach dependent) characteristics. In a first phase, a series of blind test simulations at wind tunnel conditions were performed for both basic and optimised configurations. In a second stage, the numerical results on both the baseline and optimised ERICA geometries were compared with the acquired wind tunnel data. Finally, the numerical models already tested and validated were used for the assessment of the aerodynamic performance of the optimised ERICA fuselage at full scale conditions (Mach = 0.58), including the rotor effects.