This aircraft is used, amongst other purposes. for aerial surveying for the Ordnance Survey (hence, I suppose,-OSGB). Flight Images, through the wholly owned subsidiary company Aerial Support Services, supply the aircraft and the pilots to Getmapping.com, who in turn carry out the aerial surveys for various clients. Look closely and you will see some fluffy dice hanging in the aircraft. Behind this is a large grey box, part of the Vexcel Ultracam-D large format digital aerial survey camera.
This photo was added on 28 February 2018, and has since been viewed 51 times.