ACAS(机载防撞系统)作为一种不依赖于地面空中交通管制系统的机载设备,对于减少和防止航空器相撞、保证飞行安全具有重要作用。简单地说,ACAS其实就是一个小型的机载SSR(二次监视雷达)。它在航空器飞行过程中能够接收到与自己距离较近并安装了SSR应答机的航空器的基本信息,包括航空器的位置、高度、运动方向和速度等信息。ACAS通过对这些基本信息进行处理,能够对两机(或多机)之间的安全性进行分析和评估,然后针对得出的安全性结论做出相应的反应经(包括TA(Traffic Alerl)——交通警戒信息和RA(Resolution Advisory)-决策信息),提醒航空器驾驶员采取相应 ACAS (Airborne Collision Avoidance System), an airborne equipment that does not depend on ground-based air traffic control systems, plays an important role in reducing and preventing aircraft collisions and ensuring flight safety. In short, ACAS is actually a small airborne SSR (Secondary Surveillance Radar). It is capable of receiving basic information about an aircraft that is close to itself and equipped with an SSR transponder during the flight of the aircraft, including information such as the aircraft’s position, altitude, direction of movement and speed. ACAS processes these basic information to analyze and evaluate the safety of the two machines (or multiple machines), and then make corresponding response to the conclusion of safety (including TA (Traffic Alerl) - - traffic alert information and RA (Resolution Advisory - decision information) to alert aircraft pilots to take corresponding