From the editors of the sense and avoid special issue

Unmanned Aircraft Systems (UAS) have been a growing topic in the engineering community and the news, worldwide, over the past 10 years. UAS are big business-there has existed a military and defense need for UAS, large and small, and there is a rapidly growing market for the commercial use of UAS. In parallel with the growth in interest, the remarkable growth in the wide array of enabling technology such as motors, control and stabilization systems, communications capabilities, and sensors have greatly enhanced the capabilities that can be packed into even the smallest unmanned vehicle.