Example 2: 



The Hellgate Fire of April 18, 1%5, as reported by Taylor 

 and Williams (1967), burned in forest cover of pine and oak 

 with heavy litter and slash. Rapid spread with crowning and 

 spotting occurred from 1350 to 1500. Maximum rate of 

 spread was from 1400 to 1430 at 1 10 chains/h to the east. 

 Wind shifts started to occur after 1430. The wind reduction 

 was 0.332 for the double ellipse //w ratio to match field 

 observations. These suggest the fire growth was controlled by 

 the surface fire even though there was crowning and spot- 

 ting. The wind reduction factor of 0.332 for 1430, 1500, and 

 1600 matches Albini and Baughman's (1979) values for open- 

 stocked, intolerant young to mature species, 40 to 100 ft 

 (12.2 to 30.5 m) tall. The fit of the double ellipse shape is 

 shown in figure 10. 



Example 2. The Hellgate Fire In Virginia was detected at 1335 on April 18, 1965, 

 In an area with heavy litter and slash on the surface. The heavy surface fuels 

 contributed to the fire quickly crowning out in the pine and oak overstory. 



Variable Documented Simple ellipse Double ellipse Double ellipse 

 values values values adj. values 



Time 1400.0 hours 



Area 



40.0 acres 



40 



39.5 



40 



Perimeter 



1.0 mile 



1 



1 



1.0 



Distance 



.4 mile 



.4 



.4 



.4 



Windspeed 



SW 15-20.0 mi/h 





6.6 



7.7 



//w 



2.5:1 



2.2:1 



2.3:1 



2.5: 



Time 



1430.0 









Area 



243.0 



243 



235 



243 



Perimeter 



2.8 



2.8 



2.7 



2.7 



Distance 



1.1 



1.3 



1.1 



1.1 



Windspeed 



SW 30-50.0 





10.0 



9.5 



i/w 



3:1 



3.3:1 



3.2:1 



3:1 



Time 



1500 









Area 



485 



485 



481 



485 



Perimeter 



3.3 



3.3 



3.4 



3.4 



Distance 



1.2 



1.3 



1.2 



1.2 



Windspeed 



SW 15-20.0 





5.8 



5.5 



i/w 



2.1:1 



1.8:1 



2.1:1 



2.1: 



Time 



1600 









Area 



756 



756 



700 



756 



Perimeter 



4.0 



4.0 



4.1 



4.1 



Distance 



1.4 



1.4 



1.4 



1.3 



Windspeed 



SW 15 





5.0 



3.6 



//w 



1.8:1 



1.6:1 



2:1 



1.8: 



11 



