1. Air tanker drop patterns
- Author
-
Ryan Becker, Elise Alméras, Amélie Chassagne, Dominique Legendre, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - INPT (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), United States Department of Agriculture - USDA (USA), Institut de mécanique des fluides de Toulouse (IMFT), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées, San Dimas Technology and Development Center (San Dimas, USA), and Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE)
- Subjects
Ecology ,Meteorology ,[SDE.IE]Environmental Sciences/Environmental Engineering ,Drop (liquid) ,Gaussian ,Mécanique des fluides ,Significant difference ,Firefighting ,Poison control ,Forestry ,Drop pattern ,Mechanics ,Ingénierie de l'environnement ,First order ,Modelling ,[SPI.MECA.MEFL]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Fluids mechanics [physics.class-ph] ,symbols.namesake ,Geography ,Drop tests ,symbols ,Systems design ,[PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph] - Abstract
International audience; Ground patterns of liquid aerial drops for combating wildfires are considered. Based on a significant number of drop tests performed using different airplanes and helicopters, a simple model for the length, the width and the coverage distribution is presented. At first order both the length and the width of the drop pattern can be described using simple relations despite the significant difference between the conditions of the drop tests considered. These relations include factors that can be manipulated during aircraft and release system design, as well as during aerial firefighting operations. The liquid on the ground follows a Gaussian distribution that makes possible an original prediction of the maximum coverage level on the pattern centreline confirmed by the experiments. The difference between gravity systems and recent pressurised systems is also discussed. We show a clear difference between gravity systems and pressurised systems. The width is larger for pressurised systems, resulting in a smaller coverage for the same condition of drop.
- Published
- 2014