This paper deals with 5-axis milling of hydraulic blades. The issue developed is essentially linked to problems due to the transition from 3 to 5 axes. A specific attention is done to the Inverse Kinematics Transformation (IKT) which can be source of incoherent behavior during machining due to possible multiplicity of solutions. Such behaviors may lead to slowdowns during machining which affect productivity. Moreover, geometrical surface finish may be altered. To study this phenomenon, we propose to machine a test part with the objective to reach the required quality while preserving productivity. After the analysis of the problems linked to the IKT through specific trajectories we propose solution to solve such problems, based on the local modification of the trajectory. The context of the work is a collaboration between the LMH and the LURPA.