De-icing fluid flow-off from a flat plate subjected to an accelerating airflow was studied both experimentally and using computational fluid dynamics (CFD) simulations. The experimental tests were carried out in Aalto University’s 2 m×2 m Low Speed Wind Tunnel using two different flat plate models, with chords of 0.6 and 1.8 m. The OpenFOAM software library was used in the CFD simulation for the 0.6 m flat plate model. Both measurements and CFD simulations supported the assumption that the solitary waves dominating the flow-off process were kinematic, mass transporting, in nature. For the first 50% of the fluid thickness decrease, the wave speeds and the mean fluid flow speed are almost linearly dependent on the wind tunnel speed on both flat plate models. The fluid thickness at the end of simulation predicted well the measured value.