Before revision: The corresponding formula , required to determine the required D-value of a coupling, is: D (kN) = 9.81 x (Gross Vehicle Mass X Gross Trailer Mass)/(Gross Combination Mass).
After revision: The corresponding formula for a truck and trailer combination, used to determine the required D-value of a coupling, is: D (kN) = 9.81 x (Gross Vehicle Mass X Gross Trailer Mass)/(Gross Combination Mass).