EARLY INSTRUMENT FLYING — DOOLITTLE 353 



In 1953, a FIDO installation was made at the Los Angeles Inter- 

 national Airport at a cost of $1,325,000 for installation, modification, 

 and test. While the installation appeared to handle moderate fogs 

 fairly well, it did not satisfactorily disperse dense fogs where the 

 visibility was one-eighth mile or less. The dispersal difficulties 

 seemed to arise from the great amount of heat required, the airport 

 configuration, and the movement and intrusion of the fog. Further 

 operational problems resulted from infrequent use of equipment and 

 the high cost of installation, maintenance, and operation. It was 

 also anticipated that there would be difficulty experienced in moving 

 passengers to and from the airport and in moving aircraft to and 

 from the cleared runway when the fog was really dense. The follow- 

 ing year the FIDO program was abandoned at Los Angeles. 



It appears that FIDO is a successful way of coping with intense 

 fog only when the air is comparatively still. When there is any con- 

 siderable movement of the air and fog — particularly if the movement 

 has a component across the runway — the cleared airmass moves on 

 and new fog comes in faster than it can be dispersed. Difficulties 

 have also been experienced in an absolutely dead calm owing to 

 conduction, particularly at runway intersections and elsewhere where 

 there were no burners. 



The Full Flight Laboratory's first experience with FIDO occurred 

 in 1929. Mr. Reader, of Cleveland, operated a gravel pit and utilized 

 a large blowtorch type of heater to dry the gravel and sand. He 

 observed that if there was an intense fog when he turned the heater 

 on, the fog in the immediate area dispersed. Learning of the Gug- 

 genheim fog-flying experiments, he wrote giving information of his 

 experience and advising that he was interested in helping to solve 

 the fog problem. He was invited to bring one of his heaters to 

 Mitchel Field, where it was installed just east of the last hangar. 



For several months thereafter we waited in vain for a dense fog. 

 Finally, on September 24, 1929, it came. Someone, I think it was 

 Jack Dalton, awakened just before daylight and noted that there was 

 a zero-zero fog covering the area. Our gang was quickly called to- 

 gether. We immediately notified Mr. Reader, who arrived shortly 

 thereafter. Mr. Guggenheim was also notified, but he had to come 

 from Port Washington and didn't arrive until later. The equipment 

 was fired up, but the fog did not disperse except in the immediate 

 vicinity of the blowtorch. The experiment was a disappointing 

 failure. At the time we considered the concept impractical, and the 

 equipment was removed. 



In retrospect, it appears that the trouble was probably fog move- 

 ment or possibly the absence of a mineral mass to store and reflect 

 the heat. Also, for satisfactory fog dispersal over a considerable area, 



