 Although the results gained by the CAM ships and their Hurricanes were not great in enemy aircraft shot down, the aircraft shot down were mostly Fw 200 Condors that would often shadow the convoy out of range of the convoy's guns, reporting back the convoy's course and position so that U-boats could then be directed on to the convoy.The CAM ships and their Hurricanes thus justified the cost in fewer ship losses overall.One of the more important developments was ship-borne direction-finding radio equipment, known as HF/DF (high-frequency direction-finding, or Huff-Duff), which started to be fitted to escorts from February 1942.