Fixed-wing unmanned aerial vehicles (UAVs), sometimes referred to as UAS/RPAS/drones, are aircraft that operate without a human pilot onboard. They are controlled either remotely by a human operator or autonomously via onboard computers.
Fixed-wing UAVs fly by utilising the lift generated by the aircraft’s forward motion and the shape of its wings. Fixed-wing UAVs can be self-propelled, pure gliders (vehicles whose free flight does not rely on a method of propulsion) or a mixture of the two.
Self-propelled fixed-wing UAVs typically rely on forward thrust generated by a propeller turned by an internal combustion engine or electric motor, and gliders are launched either by a winch launcher or by being towed by another aircraft. In both cases, the ailerons, elevator and rudder control the roll, pitch and yaw of the drone.
In addition to batteries and conventional petrol or diesel engines, powered fixed-wing UAVs can operate on other energy sources such as solar power and wireless power delivery using lasers.
Smaller fixed-wing UAVs (sUAS) can be hand-launched by the operator simply throwing them into the air. Larger and heavier drones require a more complex method of getting airborne, such as a catapult or a runway, or being launched from a larger aircraft.
Manned aircraft are often subject to greater minimum height restrictions than unmanned aircraft. This means that UAVs can often fly under cloud level and are less affected by problems caused by strong winds and lack of visibility. UAVs are also able to enter dangerous or difficult-to-reach environments without placing a human pilot at risk.
Compared to rotary aircraft of a similar size, fixed-wing UAVs can usually carry heavier payloads for longer distances and flight times while using less power. This makes them well-suited to covering extended distances for missions such as mapping, surveillance and defense where endurance can be an important factor. They may also be better equipped to survive technical failure in the air, as many designs incorporate natural gliding capabilities in the event of loss of propulsion.
Fixed-wing UAVs may not be suitable for fixed inspection applications where an aircraft may be required to hold a very precise position in order to capture still images such as the serial number of a pylon or minute damage to structures.