Method for carrier aircraft task flow safety analysis based on TPN

With tight timing, sequencing and compact, the time error of any task flow activities of carrier aircrafts may result flow fracturing, leading to unsafe task. Currently, the research in the carrier aircraft safety is mainly focused on the quality of its flight dynamics modeling and simulation, while for carrier aircraft task flow analysis, its improvement, and safety induced by the time factor, there are few researchers involved in these areas. This paper introduces analysis methods of carrier aircraft task flow safety, which is based on TPN (Time Petri Net). The method could compute the task risk and the risk probability by means of simulations, and proposed the advice to reduce the risk. This paper mainly discusses the carrier aircraft task flow safety problems induced by time factors, based on TPN method. This method included four steps as follows. Fist, the definition of TPN and its mathematical transformation rules are introduced. Second, the task flow safety bound is fixed on with the character of the task flow. Third, the task flow safety is analyzed from the time constraint in the TPN model. Four, the risk probability of the task system is computed by the TPN simulation rules. Five, the key events most affecting the carrier aircraft task is located, and the measures and advice are proposed to improve the task flow to enhance the task safety. Finally, this method is applied in the carrier aircraft task flow safety analysis by an example. Foundation on the characteristics of carrier aircraft task flow, carrier aircraft task system safety analysis method is introduced. The method can compute the task system risk probability, which is induced by the time factor, and can located the key events impacting the task safety, and proposed the measures and advice to improve the task system safety. This paper shows the task safety analysis approach by a USA navy carrier aircraft takeoff task flow example based on TPN methods. The result shows that the method is feasible and efficient.