In the manufacturing process, the test phase is considered the most important challenge for designers of safety-critical avionic systems found in modern helicopters. Indeed, these systems often operate in uncertain conditions and they must provide safety, fault tolerance, and deterministic timing guarantees. For large range of helicopters, the functioning of the different system units is checked using several software and hardware environments. Unfortunately, this test methodology increases the time-to-market and the cost of the final product. Focusing this issue, we propose a generic test environment that can adapt easily to the helicopter range and the Unit-Under-Test (UUT).Within this environment, we conceived a hybrid CPU/FPGA architecture in order to design innovative avionic test systems that meet performance and flexibility goals. Furthermore, we defined an efficient test methodology that favors the reuse of hardware and software models, the adaptability of the system according to the scenario, and the interoperability of heterogeneous units. The presented case study shows the strong impact of our environment to reduce the complexity of the test phase. The Eurocopter corporation intends to adopt this environment as a part of the next generation test benches.