3MODEL OVERVIEWA spreadsheet based procedure for estimating airtanker initial-attack performanceExceptional precision and flexibility in specifying the spatial distribution of fire startsExact flight-distance moments are computed and then applied in a user friendly model
4COST ESTIMATION EXAMPLE Use of Dobson's data (1965) to estimate the cost of the Canadair CL-215 for "one-strike initial-attack" as described by Hodgson and Newstead (1978) and McDonald (1979).
5DOBSON’S DATA Cost = 1.15 + 0.0891 Dist + 0.0449 Dist2 Where cost is given in cents per litre of airdropped water and Dist(ance) is the one-way flight distance from the airbase to the fire in 100’s of kilometers
6ONE-STRIKE INITIAL-ATTACK In the “one-strike initial-attack” model for skimmer aircraft it is assumed that it will drop water scooped from nearby sources until refueling becomes necessary thus ending initial-attack by that particular aircraft.
7MODEL ANALYSIS A Microsoft Excel program is used to analyze the airtanker initial-attack model- Existing airbases can be evaluated- The optimal airbase location can be identified- Constrained optimization of airbase locationmay be done
10GENERATING MODEL RESULTS 6GENERATING MODEL RESULTSDefine the regions with bounding line segmentsAssign fire occurrence probabilities to each regionLocate the airbase if appropriateEnter the constraint(s) if appropriateRun the Excel program and examine results
13COMPARATIVE ADVANTAGES - Generates exact moments of the flight-distance distribution- Models areas, lines and points as possible fire-startlocations- Provides exceptionally fast computational speeds includingoptimization- Employs a commonly available and familiar spreadsheetprogram- Offers high internal consistency due to its programmingsimplicity- Is solidly based on analytical procedures vetted throughrefereed-journal articles
14MODEL DEVELOPMENT - NEXT PHASE Front-end for GIS data importingExcel macros for data formattingScaled-up proof-of-concept run
15REFERENCES CITED1. Dobson, N.R "The economics of the Canadair CL-215 in the waterbomber and passenger transport roles." Canadair Ltd., Montreal, Quebec. OER p.2. Hodgson, M.J. and R.G. Newstead “Location-allocation models for one-strike initial attack of forest fires by airtankers.” Can. J. For. Res. 8(2):3. McDonald, C.S “Air tankers in Alberta.” In: Proceedings of the International Fire Management Workshop, Oct. 31 – Nov. 1, D. Quintilio (ed.), Edmonton, Alberta. Northern Forest Research Centre Information Report NOR-X p.
16PICTURE CREDITS 1 John McColgan, Fairbanks, Alaska 23456