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The Sundance Fire in northern Idaho 

 stands as a giant among several big fires in the 

 Northwest during the summer of 1967. The 

 magnitude of this fire resulted from a combi- 

 nation of conditions seldom occurring simul- 

 taneously — a prolonged dry period, persist- 

 ent high temperatures, sustained winds during 

 the fire run, and an uncontrolled 4-mile fire 

 front. These conditions produced a rapidly 

 moving fire that burned over a large area and 

 released an awesome quantity of energy. In a 

 period of only 9 hours this fire traveled 16 

 miles, engulfed more than 50,000 acres, re- 

 leased millions of heat units, snapped and top- 

 pled hundreds of trees, and destroyed much of 

 the storage capacity of the watersheds. 



The Sundance Fire started its major run on 

 September 1, 1967, at approximately 2:00 

 p.m. (1400 P.d.t.) and by 11:00 p.m. (2300 

 P.d.t.) it had completed the run. Shortly 

 after the major run, personnel from the 

 Northern Forest Fire Laboratory were as- 

 signed to the fire staff as fire behavior offi- 

 cers, to predict fire behavior and advise the 

 control teams. At the same time, other NFFL 

 personnel were assigned to a research team 

 responsible for investigating the physical phe- 

 nomena of this fire and for documenting its 

 historical development. Their investigation 

 was actually a detective job, since only evi- 

 dence remaining on and near the burned area, 

 eyewitness accounts, and records kept by the 

 various agencies were available for interpret- 

 ing the events. This paper presents the best 

 estimates of fire phenomena that could be 

 made by the research team, using the available 

 information. The progress of the fire, its in- 

 tensity, the fuel being consumed, the attend- 

 ant weather events, and other special condi- 

 tions were analyzed from a multitude of sepa- 



rate observations gathered from both official 

 sources and individuals. 



When a forest fire "blows up," the people 

 directly involved are busy moving equipment, 

 materials, and firefighters to new locations, or 

 planning new attack procedures, and their im- 

 pressions are often confined to a single area or 

 phase of the fire's activity. In reconstructing 

 the fire's movements, any one person's 

 account would have been of limited value. 

 The magnitude of this fire was such that 

 many different people observed it at many 

 different locations. One of the earliest jobs 

 for the research field team was to interview as 

 many people as possible who had observed or 

 participated in the fire activities on Septem- 

 ber 1. Interviews from 24 people contributed 

 to the determination of fire front location, 

 rate of spread, type of fire, and energy release 

 rate at specific times. 



The investigating team has attempted to 

 sort out the details of a violently eventful 

 period of time and construct from them a co- 

 herent account of the phenomena of a partic- 

 ular fire. A general conception of what was 

 happening where and when as the fire pro- 

 gressed is necessary to understanding of the 

 physical phenomena. Therefore this paper 

 begins with a description of the geographical 

 area and a narrative of the movement of the 

 fire. The approach to study of certain major 

 factors in the fire development is then ex- 

 plained, and the values calculated from the 

 data are given in a chronology corresponding 

 to the fire's major run. A more detailed dis- 

 cussion of significant features of the fire then 

 follows, leaving for the appendixes informa- 

 tion on methods of calculation and experi- 

 mental procedures that helped the investi- 

 gators to draw their conclusions. 



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