Research On Carrier-based Aircraft Landing Condition And Wave-off Decision Technology

The landing condition of carrier-based aircraft is very tough. To ensure safety and accuratylanding, and to let pilots make right wave-off decision immediately and take some actions whencarrier-based aircraft deviates from ideal glide path in case of several disturbances during landingprocess are two key points of carrier-based aircraft auto landing. This paper studies the two keytechniques bases on the analysis of influence factors to carrier-based aircraft landing condition, andthe wave-off decision technology of carrier-based aircraft, respectively.For analyzing the influence factors to carrier-based aircraft landing condition, at first, the airwake model has been built by establishing the connection between deck wind and every componentsof air wake. The effects that caused by sea state, vehicle speed, vehicle shape and several factors toevery components of air wake are studied. The simulation results are presented in this paper and theeffect of different influence factors on air wake can be obtained from the results. Secondly, one kindof intelligent flight control technology based on model reference fuzzy adapting method is proposed.The air wake is restrained by the method of model reference adapting system and fuzzy automaticself-adjusting. The simulation results of air wake in the cases of3-6sea states are presented in thispaper. The results indicate that the intelligent system can increase the accuracy of landing forcarrier-based aircraft, and this control system has strong parameter adjusting capability. Finally, thedisturbance ahead of the bow has been built for the first time, and the effects of its each componentare analyzed. By establishing the connection between deck wind and every components of disturbanceahead of the bow, the effects caused by sea state, vehicle speed, vehicle shape, and vehicle weight, tothe components of air wake are studied.For the research on wave-off safe decision of carrier-based aircraft, at first, the wave-off lowerboundary criterion is improved, and the upper boundary criterion is defined and proved according tosafety requirements. Secondly, a comprehensive wave-off decision system based on improvedwave-off boundary criteria is designed. This system combines the wave-off decision system based onsmall perturbation equations with the wave-off decision system based on terminal predictionequations together, and considers the factors of air wake, deck movement interference factors, whichcan ensure the perfection and feasibility of this wave-off boundary. The wave-off zone and wave-offboundary are provided, which is very useful for real applications. Finally, the simulation results of thissystem for different landing status are presented, which indicate that this new system can judgewhether aircraft is in the wave-off zone and whether it is safe, so it can increase the efficiency andsafety for carrier-based aircraft landing.