Plane’s astrodome made navigating by stars possible

Like the 16th century sailing ships of Britain’s Royal Navy, the crew of the FHC’s Avro Lancaster found their way at night by using the stars. To properly operate a sextant, a navigator requires a 360-degree view of the sky. In a streamlined airplane, this vantage point was gained with the help of a bulging Perspex bubble, called an astrodome. In the days before GPS, both altitude and longitude could be determined, to an amazingly accurate degree, with the help of celestial navigation.