Aircraft piston engine load distribution in steady state operating conditions

The article presents the results of statistical analysis of aircraft piston engine operational parameters during normal operating conditions. Test was carried out on ultralight gyroplane Tercel produced by Aviation Artur Trendak equipped with CA 912 ULT piston engine. Research was conducted under normal operating conditions of the autogyro and data was collected from 15 independent tests including a total of 14 flight hours conducted during training flights. Engine and flight parameters were recorded at 9 Hz during each flight using on-board Flight Data Recorded system. The data collected was subjected to statistical analysis to determine the statistical distribution of parameters defining the engine's operating condition. The analysis covered engine speed, intake manifold pressure, oil temperature, head temperature and exhaust gas temperature. The results were presented in the form of histograms showing the characteristic ranges of the parameters in aviation engine operation. An analysis of the rate of change of the analysed parameters was then carried out. This was the basis for defining the engine's steady state. The results showed that the steady state of the engine under these operating conditions accounted for more than 78% of the total engine operating time. A Power Consumption Ratio indicating the load range of the engine was determined for steady states. It was shown that most of the time the motor operates at an average load of between 50% and 80% of the nominal value.