The commercial aviation in the last twenty years has doubled the Revenue Passenger Kilometers (RPKs), and forecast estimates the global fleet will be almost the double over the next 20 years. In this competitive market, Maintenance, Repair and Overhaul (MRO) industry will demand innovative solutions, a key role to sustain such increase will be the digitalization and automation of the maintenance procedure, such as: integration of collaborative robot, collecting data, connected tools and machine learning. Those innovating tools, are applied in order to create an advanced diagnostic for primary flight control, where the Electro-Hydraulic Servo-Actuator (EHSA) is the most spread technology that is used.