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A multirotor trim module is developed for the HPCMP CREATETM-AV Helios rotorcraft simulation code. Trimmed free-flight simulation results are presented for two multirotor configurations, using rotor frequencies and aircraft attitudes as the control variables. The loose-coupling procedure is used to achieve trim, where aerodynamic loading on the rotor blades and fuselage are computed using a simplified aerodynamic model, and modified at each coupling iteration using the airloads computed by the higher fidelity CFD based aerodynamics. Two different optimization methods are tested: a least-square regression algorithm, with the norm of the loads at the center of gravity as the objective function, and a nonlinear constrained optimization code, with the total power as the objective function, and with constraints applied to satisfy trim. First, a commercial small-scale UAV is simulated in forward flight. A reference model for midscale UAM applications is then trimmed in hover to demonstrate the module’s ability to model and trim a complex configuration.