The Charles Close Society for the study of Ordnance Survey maps

Digital Images Archive

Quarter-inch (1:253,440) Great Britain Third Edition sheet 1 (Royal Air Force Special Edition)

71. The earliest known Ordnance Survey aviation maps were based on the quarter-inch second editions, without hill shading or graticule, and sectioned usually into twelve-inch square sheets, including marginalia at the top. They were issued in the form of Air Packets by the Admiralty War Staff Intelligence Division for the use of pilots of the Royal Naval Air Service during the first world war. Following a few experimental sheets, a new national map, covering both England and Wales, and Scotland, was published on the new Third Edition map, beginning in 1925. The specification was revised, enhancing features of particular use to aviators. The earliest version, the 'Royal Air Force Special Edition', was for the use of both service and civilian pilots, and had a two-inch alpha-numeric squaring system in black. This was superseded within three years by maps prepared separately for civilians (with a graticule) and the services (with the War Office Cassini Grid). Very few copies of the 1925 map even of England and Wales seem to survive, and rarer still are the sheets covering Scotland.

From a copy in private collection