Cracking Aircraft Windows with Directed Sound Waves
Currently we have talking glass technologies, which vibrate windows and can be used to whisper sounds. These same technologies, which are currently produced with acoustic transducers attached to the windows can also be replicated from a distance with directed sound. Since glass, Plexiglas etc are brittle a certain type of vibration will cause them to crack and thus a breach in the aircraft at altitudes above a certain height become immediate problems for the pilot, taking precedence over mission and going to the heart of a human's need for self preservation.
Recently a Delta Airlines flight had to make an emergency landing after the airplane's windshield cracked. Often flights with breaches in the pressurization system are forced to land or fly below twelve thousand five hundred feet where the oxygen percentages in the air are livable for humans. When even a crack appears pilots must take action as the concerns of loss of cabin pressure take priority.
A weapon of this type, which can crack windshields of aircraft would deter manned aircraft from entering a safety zone containing our military or civilian assets. Such a weapon would be inexpensive to use and save millions of dollars in anti-aircraft missiles, which often fail to hit their mark when the enemy has sufficient counter measures.