The main function of the brake system is to decelerate the aircraft on the ground, a function that is directly linked to the safety of the aircraft's operation. Furthermore, brake performance has a direct impact on the weight that can be carried and therefore on an airline's operating cost. Therefore, it is very important to develop an optimized brake system to maximize braking performance in various runway conditions. Modeling and simulation are one of the ways to optimize this dimensioning in addition to reducing development costs. The objective of this paper is to present a modeling and simulation methodology in order to predict the behavior of the aircraft integrated with the brake system in the different scenarios of use of the brakes. This methodology allows evaluating the performance of the integrated system, as well as mitigating possible problems during system development. Due to its complexity, a model to assess the performance of the brake system is composed of several integrated models. These models are developed by different areas of the company and even by component suppliers. In addition, they also evolve in complexity throughout aircraft development. These models include pilot model, brake control model, brake valve model, brake assembly model, engine model, aerodynamic model, aircraft model, landing gear model, and wheels/tires model. All these models are integrated into a single model and simulated in a set of predetermined scenarios. These scenarios consider the different friction conditions of the runway, aircraft weight and center of gravity, asymmetric braking and failure cases. This methodology has been used with great success throughout some programs, allowing to increase the quality and maturity of the company's brake systems.