The brake system performs an important, safety-related function in aircraft operation throughout the world nowadays. However, the requirement of an acceptable performance and satisfactory reliability has become stricter as the aircraft landing weights and speeds increased substantially along the last decades and the regulatory authorities improved their certification basis requirements aiming a safer operation. Therefore, the brake system design, architecture and functionalities have evolved through the years and the development of the antiskid system, part of the brake system of several aircraft since 1940s, comprised an important milestone in aircraft brake system history. Besides the main function of preventing the locking of braked wheels, the antiskid system is normally also responsible for avoiding wheel braking at the instant of the first contact of the tires with ground during landing. The system also provides indication to the crew in case of system failure and helps minimize the inadvertent yaw suffered by the aircraft in case of passage of the tires on surfaces with different friction coefficients. As a result, the appropriateness of the brake system performance, which is mostly supplied by hydraulic power in recent commercial and military aircraft, shall be completely verified in normal and faulty conditions, as well as in all expected operational envelope. For that purpose, model simulations, rig tests and flight test campaigns are usually applied. Therefore, the present work aims to demonstrate the use of a computational model of a hydraulic brake system, parameterized in LMS Amesim® software, to assess the behavior of system relevant variables in normal operational conditions and the potential effects of typical failures in system performance. In addition to help support the verification process of system compliance with performance and safety requirements, such approach could also be applied for early identification of failures and operational problems still during the product development phase, highlighting the gains of applying the aforementioned tool in the context of aeronautical systems engineering.
Keywords: System, Modeling, Amesim, Hydraulic, Failure