Fog Investigation and Dispersal Operation Fog Investigation and Dispersal Operation ( FIDO ) ( which was sometimes referred to as " Fog Intense Dispersal Operation " or " Fog Intense Dispersal Of " ) was a system used for dispersing fog from an airfield so that aircraft could land safely . The device was developed by Arthur Hartley for British RAF bomber stations , allowing the landing of aircraft returning from raids over Germany in poor visibility by burning fuel in rows on either side of the runway . The FIDO system was developed at the department of chemical engineering of the University of Birmingham , United Kingdom , during the Second World War . The invention of FIDO is formally attributed to Dr John David Main - Smith , an ex - Birmingham resident & Principal Scientific Officer of the Chemistry Dept of the Royal Aircraft Establishment at Farnborough , Hants , and as a courtesy the joint - patent ( 595 , 907 ) held by the Ministry of Supply was shared by the department head Dr Ramsbottom as was normal practice at that date . This formal government recognition is enshrined in an Air Ministry postwar letter to the late inventor ' s late widow and held by the son Bruce Main - Smith ( February 2008 ) . It also deals with the lesser role of those developing support equipment , notably the FIDO burner . " It is my memory " , writes B Main - Smith , " that much of the airfield installation was pioneered at Hartford Bridge Flats airfield ( aka Blackbushe near Yateley , Surrey ) a convenient few miles from the RAE ' s Farnborough aerodrome . " Though JD Main - Smith co - owned the FIDO patent , no royalties accrued from any UK civilian usage after World War II as there was none , it being too petrol - hungry . At an attempt to quantify the saving of aircrew life , B Main - Smith suggests possibly 11 , 000 airmen but not all would be fit to fly again . . . " It is difficult for the modern ( 2008 ) UK resident to comprehend what World War II fogs were like . It was not uncommon for a person to be unable to see the hand at the end of an outstretched arm . The post - war Clean Air Act hugely ameliorated UK fogs " , comments B Main - Smith . The system . The device consisted of two pipelines situated along both sides of the runway and through which a fuel ( usually the petrol from the airfield ' s own fuel dump ) was pumped along and then out through burner jets positioned at intervals along the pipelines . The vapours were lit from a series of burners , producing walls of flame . The FIDO installation usually stored its fuel in four circular upright tanks built at the edge of the airfield with a low brick bund wall in case of leakage . The tanks were usually encased in ordinary brickwork as protection from bomb splinters or cannon fire . When fog prevented returning Allied aircraft from locating and seeing their runways to land , they would be diverted to FIDO equipped aerodromes . RAF night bombers which were damaged on their missions were also diverted to FIDO airfields due to the need to make certain they could land when they arrived . When FIDO was needed , the fuel pumps were started to pour flammable liquid into the pipe system and a jeep with a flaming brand lashed to its rear drove fast down both sides of the runway to ignite the fuel at the outlets in the pipes . The burners were sometimes ignited by men on bicycles or by runners on foot . The result was a row of flame along the side of the runway that could be seen for a great distance from the air . The heat from the flames evaporated suspended fog droplets so that the Allied aircraft could have suitable visibility to find the airfield and land . Once landed , the crews would find shelter where they could , and their planes would be refuelled and , if needed , repaired before flying back to their normal bases the next day . The procedure for aircrew before the introduction of FIDO . Before the introduction of " FIDO " , fog had been responsible for losses of a number of aircraft returning from operations . Often large areas of the UK would be simultaneously fog - bound and it was recommended procedure in these situations for the pilot to point the aircraft towards the sea and then , while still over land , for the crew to bail - out by parachute , leaving the aircraft to subsequently crash in the sea . With raids often consisting of several hundred aircraft , this could amount to a large loss of bombers . The use of FIDO . " FIDO " used huge quantities of fuel , as much as 100 , 000 gallons [ 125 , 000 US gallons , 450 , 000 litres ] per hour . Over twice this amount was used by airfields with longer runways such as RAF Carnaby . Large fuel storage tanks filled with low - grade petrol and possibly kerosene and other fuel were connected by pumps to provide this fuel to the runway pipes . Although extravagant in the use of fuel consumed , the device more than made up for the costs involved in the reduction in aircraft losses . " FIDO " systems were used at many RAF Station s in England during World War II . The last " FIDO " - equipped airfield at which a system was maintained was RAF Manston , the system being available for emergency use as late as 1952 . Due to the high costs involved use had to be reported to the Air Minister . Initial installation of " FIDO " was designed and constructed along Runway 1 at London Heathrow Airport but the pipes and other fittings were never installed . FIDO was also installed at North American airfields including Arcata , California , Naval Air Station Whidbey Island , and Amchitka and has been used to bring commercial planes into fog - covered airports in the United States .