The paper presents features and implementation of a shared redundant approach to increase the reliability of networked control systems. Common approaches based on redundant components in control system use passive or active redundancy. We deal with quasi-redundant subsystems (shared redundancy) whereas basic features are introduced in the paper. This type of redundancy offers several important advantages such as minimizing the number of components as well as increasing the reliability. The example of a four-rotor mini-helicopter is presented in order to show reliability improving without using any additional redundant components. The main aim of this paper is to show the influence of the load increasing following different scenarios. The results could help to determine the applications where quasi-redundant subsystems are a good solution to remain in a significant reliability level even if critical failure appears.