Aerial Observer- Air Force Reconnaissance.
An Aerial Observer is the functional position of gathering information visually from an airborne platform for use by military or commercial purposes. This history started when the first balloons were flown in Europe. In the early twentieth century it developed with the invention of biplanes and mono-winged aircraft.
During World War I and II there was a tremendous amount of intelligence gathered through these means. These crewmembers would use optical and photographic means to record their observations.
In the Vietnam War, aerial observers also might be Forward Air Controllers (FACs). These O-1 Bird Dog, O-2 Skymaster and OV-10 Bronco pilots would slowly fly over an area and direct bombing by radio to fast moving jet aircraft.
Observer is the Royal Navy's term for its Fleet Air Arm navigator/radar/weapons system operators, both in two seat fixed wing combat aircraft such as the Sea Vixen and F4K Phantom and anti-submarine helicopters such as the Westland Lynx. The US Navy's equivalent is the radar intercept officer (RIO).
Although today sometimes a manned aircraft is still utilized, industry and the military use both satellites and remotely piloted vehicles (RPV) for this function.