Sensitivity Analysis and Aerodynamic Modeling of eVTOL Low-speed Predicted Handling Qualities

This study explores aerodynamic modelling and the application of Sensitivity Analysis (SA) to the low-speed predicted Handling Qualities (pHQs) of a small-scale eVTOL, to identify the impact of uncertainty in modeling. The methodology integrates the statistical simulation tool Dakota with a Flight Simulation Model (FSM) to assess the propagation of input parameter uncertainties on pHQs: Attitude Quickness, Dynamic Stability, and Bandwidth. The aerodynamic analysis, conducted using the DUST aerodynamic model, determines the correct approach for computing dynamic stability derivatives. The results highlight the dependency of these derivatives on reduced frequency, emphasizing the need to consider this in FSM development and uncertainty analysis. A hybrid SA framework that combines the Morris One-at-a-Time (MOAT) method for preliminary analysis with Variance-Based Decomposition (VBD) using a Kriging meta-model for efficiency is implemented. Key parameters whose uncertainty affects pHQs, such as mass, system time delay and aerodynamic parameters, are identified using the SA. This work demonstrates how to implement a robust SA process for uncertainty analysis, to support informed decision-making in assessing the credibility of flight simulation models to be used for certification by simulation.