To estimate the effectiveness of forest machines developed technological possibility coefficient. Coefficients reflect the ability to provide a given performance of transport vehicles in the logging, the decline in the quality of the skid road surface. Method allows determining the amount of logging residues, necessary for the skid road construction. At calculating the available volume accounted for logging residues. Resources of logging residues are calculated depending on the type of timber and the length of skid road. The method allows selecting the optimum system of machines to work in these natural production conditions or schedule performance loss due to reduced carrying capacity of skid road.

Keywords: Cross country, technological passableness, forest machines, bearing capacity of soils, skid road, wood types, logging residues