- Fluid-structure interaction problems prove difficult due to the coupling between fluid and solid behavior. Typically, different theoretical formulations and numerical methods are used to solve fluid and structural problems separately. The least-squares finite element method is capable of accurately solving both fluid and structural problems. This capability allows for a simultaneously coupled fluid structure interaction formulation using a single variational approach to solve complex and nonlinear aeroelasticity problems. The simultaneous solution method was applied to aeroelasticity problems with a known analytic solution. Acheiving these exact results required unique iterative methods to balance each field's weighting factor within the simultaneous solution scheme.