A static model for partially oriented yarn (POY) production was examined in a commercial POY spinning plant. A two-level factorial, industrial experimental design was used to identify a statistical model. Three independent variables effecting the elongation at break (a POY property of interest) were selected. Namely, yarn winding speed, spinneret flow rate, and spinneret hole diameter. Elongation at break was chosen as the dependent variable. A first-order statistical model was considered to show the dependence of the elongation at break on the operating parameters: 145%; for elongation at break, the optimum values of yarn winding speed, spinneret flow rate, and spinneret hole diameter were found to be as 2938 m/min, 49.74 g/min, and 205 mum, respectively. The statistical model and Box-Wilson steepest ascent method were used.