This paper deals with an automated on-line condition monitoring and control system for gas turbine helicopter engines. This system is installed at a production test cell for gas turbine helicopter engines. The system controls the execution of various test cycles as required by the FAA Part 33 aircraft engine regulations and simultaneously acquires both performance and vibration spectral data leading to on-line performance calculations as well as diagnostics of turbine problems.The test cycles are fully automatic, the control system controls the turbine speed and the dynamometer. This is done when the test cycle being executed demands a given torque to be applied and changed or maintained throughout the cycle.The turbine performance is monitored at all times and is compared to the engine acceptance curves. The system continuously validates the performance and vibration spectral data against the limits to ensure that the turbine is operating within the manufacturer's specification. The system will diagnose problems if the points are outside the manufacturer's specification and will take the proper action to ensure the safe shutdown of the engine if the test is impossible to continue due to the severity of the problem.