For large-scale gathering or activities in cities, one main security mission is to prevent destruction from terrorists or hostiles using small aircrafts with low altitude and low velocity (such as, model aircrafts, balloons). In order to intercept a small target with low altitude and low velocity, a conventional destructive weapon (such as, an antiaircraft weapon, a firearm) is not recommended to use because of particularities of a city environment and the large-scale activity, and thus a nondestructive intercepting mode is introduced instead.
Currently domestically and abroad, a type of nondestructive weapon is a net catching system, which is directed against ground target. A “net gun,” which makes use of high pressure gas or blank as power to throw out and unfold a catching net in order to capture a criminal, is primarily used domestically to intercept the target. A “KOA” system (Ukraine), which may launch the catching net from a relatively distant location to capture the ground target, is primarily used abroad to intercept the target. Both methods mentioned above, which are nondestructive net intercepting mode, are used for catching the ground target but are incapable for an aerial target.