FIDO, or Fog Intensive Dispersal Of, was a system used at 15 airfields spread throughout England during World War Two. It was created and used to disperse fog from the airfield so that the returning bombers and other aircraft could land safely.

The system consisted of two pipes running the length of the runway that fed fuel from the airfields own supply down the length of the runway. The fuel was then lit creating huge torches of flame and heat that wold almost immediately dissipate the fog up to about eighty to one hundred feet or so depending on the severity of the fog. It was reported that the system was very loud and could be seen for almost sixty miles. It was also described as creating a scene not unlike Dante’s Inferno. The system was very expensive to use, burning almost 125,000 gallons of fuel per hour, but in terms of lives saved it was well worth the cost. Prior to this system being installed, crews would simply point their bomber out over the English Channel and bail out with of course complete loss of the aircraft.

Not all airfields had the system installed so it wasn’t uncommon for aircraft to be diverted to these fields if there primary landing area was unusable due to the low ceilings. This system is credited for saving hundreds if not thousands of lives of the crewmen who would have been otherwise unable to safely return home after a mission.