*<* I If 13b. 1X001 
373 
showing 
The second type of fire situation which our IR system is geared to 
monitoring is the wildfire during the initial burning period following detection. 
In this period of burning, the fire suppression organization makes its initial 
attack decisions and fire behavior must be predictable in order to maximize 
returns from available men and equipment, including aerial attack with retardant 
aircraft and ground suppression crews. 
Figures 7 and 8 show from 580 m an initiating wildfire in an open 
Douglas fir (PAmdotAuga mmzyCeA^A, (Mirb.) Franco) stand in south-central 
British Columbia. The fire has not yet been attacked by control forces and 
is 0.24 ha in size at this point. The timber up slope from the fire, as shown 
in Fig. 7, was recently insect killed, and potential for rapid spread of this 
fire, had it reached these fuel^ could have been great. Final size was 0.81 ha 
as control was achieved with ground and aerial attack conducted over the two 
hour period following Figs. 7 and 8 . Fire behavior was monitored at approxi 
mately five minute intervals with the IR system until control was achieved. 
Finally, the third type of fire situation in which the IR mapping system 
is engaged are research test fires in blocks of standing timber deliberately 
ignited by Canadian Forestry Service research teams. These prescribed bums 
are generally conducted on plots varying from 0.4 to 2.0 ha in size. Free burning 
fire behavior is studied in various fuels without fire suppression action being 
taken until sufficient research data has been gathered. 
Figures 9 to 12 illustrate a one ha plot of standing jack pine (PyCnuA 
bankA^ana Lamb.) which was burned intentionally after ground crews measured 
fuel quantities and moisture contents and ground sensors had been installed 
to measure 'spread rate and intensity. This research program was conducted in 
northeastern Alberta during July and August, 1974 with the cooperation of the 
Alberta Forest Service. Infrared mapping is a valuable backup to ground sensors 
and visual mapping for spread rate under such situations. 
Figures 9 and 10 show the fire in its initial spread stage 5 min. after 
ignitioi\ from a height of 1040 m. Figure 11 is the IR image of the fire 18 min. 
later, during which time the spread rate averaged 5.2 m/min. Figure 12 is a 
scale diagram of the IR images shown in Figures 10 and 11. The reference grid, 
which was laid out on the ground, enabled an accurate scale computation to be 
made without the small errors which occur when aircraft altimeter readings must 
be used, as occur on fires with no known ground distances. Ignition of the fire 
took place along the perimeter CADEFG. The reported spread rate was measured 
along line AB, corresponding to the prevailing wind direction.