An unsteady, compressible, two dimensional Navier-Stokes solver has been developed for the Connection Machine (CM-2 and CM-5). The solver has been applied to the computations of subsonic viscous flow past a pitching airfoil at Rec = 1044, (based on airfoil chord length) M∞ = 0.2, non-dimensional pitching rate Ωυ+ = 0.2 and 0.4. The algorithm for solving the Navier-Stokes equations is based on an unstructured grid of triangles. Roe's flux difference split method is employed for the inviseid fluxes. A discrete representation of Gauss' theorem is used for the viscous fluxes and heat transfer. A four stage modified Runge-Kutta algorithm is employed for the temporal integration. The algorithm is second order accurate in space and time. The implementation of the algorilhm on the Connection Machine and the investigation of the incipient boundary layer separation for a pitching airfoil are presented. The investigation of the effect of pitching rate on incipient boundary layer separation for a pitching airfoil shows that increasingly Ωυ+delays the formation of the three recirculating regions near the leading edge and results in higher values of the lift and drag coefficients.