This paper brings the first results concerning a new analytic model to evaluate atmospheric dispersion in rocket launch scenarios, namely Generalized Integral Laplace Transform Technique for Rocket effluent dispersion model. The model is constituted by three different modules, being two pre-processors (micrometeorological parameters and deposition parameters) and the dispersion program. The dispersion calculations are made through the Generalized Integral Laplace Transform Technique solution of the two-dimensional, time-dependant, advectiondiffusion- deposition equation. The results show a set of simulations using data from the Chuva Project from the Centro de Lançamento de Alcântara for both stable and unstable planetary boundary layers, in order to evaluate model performance and illustration. © 2015, Journal of Aerospace Technology and Management. All rights reserved.