Method of regulation condition assessment of turbine jet engine in flight basing on signals recorded during ground tests

During exploitation process operation quality differences may be observed between each particular machine and occurring in exploitation of one machine. These differences result from deviations of realized service process. Turbine jet engine regulation process was realized during ground tests. However, due to varying reactions of engines to external distortions, such as rocket launching, air swirl from another plane etc. as well as lack of possibility of simulation of in-flight conditions on ground (e.g. by partial choking of air intake), a situation may occur in which engine properly regulated on ground may not present sufficient efficiency in flight. Hence, the necessity to assess turbine jet engine regulation condition in flight basing on its ground tests. Research realized on computer models presenting engine operation both in flight and during ground tests indicated that real possibility of engine in flight regulation condition assessment based on its ground tests does exist. As was also noticed, with known input signal “w” and output signal “yW” recorded during engine ground tests as well as input “e” and output “u” signals from regulator during given test spectral powers and cross spectral powers of signals Swyw, Sww, See, Seu may be calculated and thus HW transfer function describing engine operation during ground test and GR transfer function describing regulator operation during given test and hence obtain transfer function HZ describing engine in flight. This grants possibility of regulation condition assessment of turbine jet engine in flight using signals recorded during ground tests.