The name “radio compass” can be a bit confusing as it doesn’t use the Earth’s magnetic field (north magnetic pole) for navigation. Strategically placed radio stations drive this compass, and it was first tested in 1920 – US Navy pilots used the technology to guide a seaplane to a target ship 100 miles offshore. It was the dawn of radio navigation, although the concept was first proven at the turn of the last century. Early pilots used landmarks and even roads to navigate, but navy pilots were limited to buoys (if there were any), possible landmarks, memory and intuition. During this first test, the USS Ohio was within a 100-mile radius of Norfolk, Virginia, on America’s east coast. A radio station on the ship allowed the “blind” twin-engine aircraft to find it with a simple receiver and pointer, and the plane flew back to Norfolk via a land-based radio station. Today, it seems a bit archaic with advanced radar and global positioning systems, but this revolutionised civilian and military aviation a century ago. There are planes flying today that still use this simple and reliable navigation method.