Built-in Test Design for Fault Detection and Isolation in an Aircraft Environmental Control System*

A novel built-in test (BIT) design method for fault detection and isolation (FDI) is presented, in which the test information extracted is maximized using parametric sensitivities derived by a system model. Two case studies are presented to demonstrate this approach. The first test focuses on fouling identification in an aircraft heat exchanger, in the presence of uncertain system inputs. The second example expands this method to a subsystem of an aircraft environmental control system (ECS) to calculate optimal conditions for component FDI.