An ex 60 Sqn Andover C1, XS596, became the UK 'Open Skies' aircraft in the late '80s/early '90s, based at Boscombe Down. It had been highly modified for 60 Sqn to carry vertical cameras and, from memory, an infrared line scan and I was told that it used to fly the Berlin corridors. The modifications made it ideal for installing the equipment required for 'Open Skies' tasks.