Abstract
Influence of a headwind (wind speed, U) on fuel consumption, fc (L/km), for highway vehicles has been made clear by us with use of increase of fuel consumption, βｆ(U). However vehicle cruising speed, v, was limited and other v remain elusive. So the aerodynamic influence coefficient, KA (v), is first studied and then headwind influence, βｆ(v), can be obtained with αＡ(u) which is increase of air resistance in vehicles due to headwinds. As a result βｆ(v) might be found practically almost constant over v increase in spite of reduction of αＡ(u).
