The flight test comes at the end of the aircraft development process and is an unique part. The purposes of the flight test are to evaluate the characteristics of the aircraft and validate its design in the real operating environment. Atmospheric considerations are key elements, when the planner of flight test establishes the flight test planning. The primary objective of atmospheric considerations is to ensure safety of the vehicle. The planning through atmospheric considerations can minimize flight cancellations caused by severe weather. In this paper, we present a program for flight suitability distinction, and develop a program for calculation of available sorties.