Flight Dynamics of a Flying Wing Aircraft Featuring the Bell Spanload

Results of a previous aerodynamics study conducted over a wing that exhibits the Prandtl Bell Spanload were implemented into a simulation environment with the intent of studying unique flight characteristics that are theorized to be presented by this spanload. However, early simulations over the dynamics show that the yawing moment due to roll rate is of higher effect than the yaw moment due to aileron deflection angle. This over-prediction of the roll-yaw coupling term has been called into question. A new method is to be tested, which implements a compact vortex-lattice (CVLM) formulation, to show the difference between the flight dynamics predicted by this new method and the stability derivative method currently in use. The analysis utilizes two initial conditions to test the differences as the dynamics propagate through time. The first, a large initial bank angle, leads to the stabiltiy derivative method diverging while the CVLM results show this to not be the case. The second condition, a wind-field representative of a stable nocturnal boundary layer over the ground, leads to much more agreement between methods before divergence occurs due to a velocity higher than that of the stability derivative linearization point. It is then agreed that, since CVLM cannot predict stall effects and other nonlinear flight regions, a hybrid approach is proposed that takes advantage of the roll-yaw coupling prediction of the CVLM and the range of condition available to the stability derivative method.