First time for me to see and photograph an autogiro. Autogiros have rotors instead of wings but unlike helicopters they are not powered so unable to hover. The rotor spins around as the autogiro is driven forward by the propeller and generates lift. Autogiros were used by the RAF to check and/or calibrate radar stations as they were able to fly in very tight circles. Indeed at one point the RAF's Radar Calibration Unit was based at Duxford for some time during WWII. Previously G-ACUU