The aircraft system laboratory is equipped with a virtual Iron Bird allowing “man-in-theloop/ hardware-in-the-loop real-time” simulations of the dynamic behaviour of an aircraft with Fly-by-Wire Flight Control Systems (FBW/FCS). The Iron Bird integrates an Engineering Test System (ETS) with hardware components such as a human pilot interface, Flight Control Computers (FCC) and an hydraulic rig for testing flight control actuators. The ETS is based on a network of PCs connected by optic fibres for high speed communications. Each PC runs a portion of the whole model (e.g. flight simulator, hydraulic actuators, control laws etc.). Thanks to parallel computing, very complex models of subsystems can run real-time simulations with steps of 10-4 sec.

The hydraulic test rig includes one of the hydraulic actuators of primary flight control surfaces and an hydraulic jack simulating aerodynamic and inertial loads. The primary actuators can be tested one by one. The actuator under test is mounted on the rig while the others are simulated by the ETS.

An hydraulic power unit supplies both the hydraulic jack and the primary actuator under test. The pressure can be modified by the ETS in order to simulate the effect of the engine rpm, according to the model of the hydraulic plant. Hydraulic as well as electrical failures can be simulated in order to verify the failure management logics and to measure failure transients.