The criteria taken into consideration for the classification of aeroplanes by categories is the indicated airspeed at threshold (VAT) which is equal to the stalling speed (VSO) multiplied by 1,3 or VS1G multiplied by 1,23 in the landing configuration at the maximum certificated landing mass.
Aircraft categories shall be based on the indicated airspeed at threshold (VAT) which is equal to the stalling speed (VSO) multiplied by 1,3 or one-g (gravity) stall speed (VS1g) multiplied by 1,23 in the landing configuration at the maximum certified landing mass.
