In this paper, the mechanisms of propagation of the damage in aluminum panels repaired with bonded composite patches of different mechanical characteristics is analyzed. The aim of this study is to analyze analytically, experimentally and numerically the advantage of the use of bonded composite patches to increase the fatigue life and to reduce the state of tension at the crack tips. The experimental results show that both static strength and fatigue life of the repaired aluminum panel has significantly increased due to the bonded composite patches. The different patches and adhesive, used for cracked panels, have provided about a 100-110% improvement in the fatigue life and a 30-35% decrease in the stress intensity factor. A comparison between finite elements calculations and experimental data has been carried out. The good agreement between the experimental data and the numerical ones has demonstrated the possibility to obtain an optimized design of bonded patches with the numerical tools.