Up to 5% of an airplane's fuel might be saved by taxiing with powered wheels. Additional benefits in conservation are reduced noise, jet blast, and emissions at the terminal area. By using the airplane onboard auxiliary power unit (APU) to operate the traction-producing drives, an airplane self-contained ground-maneuvering capability is provided. Hydraulic power transmission for the wheel drives has the advantage in satisfying large horsepower demands for a small weight and volume penalty. Variations in the drive mechanism are based on the method of transfer of power to the wheels while preserving the present method of independent braking during airplane landings.