Division 3 Determination of air drag

The constant speed test procedure shall be applied to determine the air drag characteristics. During the constant speed test the main measurement signals driving torque, vehicle speed, air flow velocity and yaw angle shall be measured at two different constant vehicle speeds (low and high speed) under defined conditions on a test track. The measurement data recorded during the constant speed test shall be entered into the air drag pre-processing tool which determines product of drag coefficient by cross sectional area for zero crosswind conditions C_d · A_cr (0) as input for the simulation tool. The applicant for a certificate shall declare a value C_d · A_declared in a range from equal up to a maximum of + 0,2 m² higher than C_d · A_cr (0). The value C_d · A_declared shall be the input for the simulation tool CO₂ simulation tool and the reference value for conformity of the certified CO₂ emissions and fuel consumption related properties testing.

F1Vehicles which are not member of a family shall use the standard values for C _d ·A _declared as described in Appendix 7 to this Annex. In this case no input data on air drag shall be provided. The allocation of standard values is done automatically by the simulation tool.