A drone for spraying liquid over field crop includes: a frame with a slender rigid beam in the middle and two base structures at the two ends, a rigid tube with an array of nozzles on elongated stems and the rigid tube is suspended below the beam structure with retractable wires, at least three propellers on motors with arms that are rotatably mounted to each of the two base structures of the frame, a power source, at least one distance detector for measuring height, an antenna for communication, an electronic control system to operate motors and sensors, a container for a liquid material and electronic valve to allow liquid in the container to be transferred and sprayed from the nozzles, and a remote controller. The drone is intended to spray liquid over a wide strip of the field with high efficiency, precision, and safety and reduced drift of sprays.
