Interagency Aviation Strategy - July 2008 - National Wildfire ...

implications for defining initial attack program performance. Programs are tested against
a set of historical fire seasons.
On the initial attack side of the equation, WIRAS models resource deployment with a
system of rules intended to closely reflect how managers make resource allocation
decisions in a multiple fire environment. This set of rules defines a hierarchy of preferred
resource responses that recognizes the fire location, behavior, management objectives,
and accessibility, among other things, but also takes into account the availability of
different kinds of initial resources at any point in time. In general, the dispatch rules in
WIRAS favor responding to a fire with local ground resources provided the response
times are reasonable given a fire’s behavior. When ground resource response times are
not reasonable, the model seeks to dispatch helitack, and finding none, will request
smokejumpers, if available. Airtanker support is determined by projected fire intensity.
If no resources are available, fires just wait and grow until resources returning from
earlier responses become available for dispatch. Fires that reach predefined sizes or
perimeters either while waiting or during suppression are declared escaped. All resources
have the ability to attack several fires on a given day depending on how quickly they can
contain fires and prepare for another dispatch.
Projected fire behavior and fuel model determines the “might” of the initial attack
response. During multiple fire episodes, new fires and those waiting for service are
prioritized based on highest fire intensity level (FIL) with a somewhat diminished priority
if located in wilderness or roadless areas.
WIRAS currently provides capabilities for evaluating regional and national resources,
Type 1 and 2 helicopters, smokejumpers, helitankers, and airtankers. The software has
some local program analysis capabilities, but these have not been fully developed.
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