Presentation on the use of “sailing” technologies to reduce CO₂ emissions and raising a question over the ability of the WLTP test cycle to account for the effect of sailing on vehicle emissions and fuel consumption performance. Sailing involves the decoupling of the engine from the drive shaft, enabling hybrid vehicles to cruise (or “sail”) on battery power alone until such time as the engine needs to be restarted to generate electricity and/or resume the torque functions.