One of the latest ideas under serious consideration by airlines to save money is electrical drive systems mounted on the landing gear that allow airliners to taxi without running the engines. The auxiliary power unit is used instead to run an electric motor mounted on the undercarriage, which in turn rotates the wheel.
Such systems can be fitted to either the nose or main landing gear. They have the potential to shave up to 80% off the fuel bill while the airliner is moving on the ground, as well as reduce associated powerplant maintenance costs and exposure to foreign object damage. Airliners would also no longer require ground tugs for push back, reducing delays. Noise levels at airports would decrease considerably.
The proportionally longer time short-haul airliners spend taxiing compared to long-haul aircraft makes them the initial target for such systems. The market is potentially huge, as the system can be installed on both new and existing aircraft.
Several companies are investigating and actively marketing electric taxiing systems. The WheelTug nose landing gear unit was developed by Borealis Exploration from 2005, when it tested the concept on an. Further trials in collaboration with Prague Airport Consulting took place in December 2010 using a , and the system is currently being marketed.
In June 2011 the German aerospace research agency DLR tested anwith an electrically driven nose wheel. and have also been working on a system since November 2011 and will install a prototype in an A320 during 2014. Service entry is expected two years later. During December 2011 , and Airbus tested a main landing gear system at Frankfurt.
Currently, WheelTug the only one with commitments from the airlines. In March it signed letters of intent withand Israir Airlines. , however, become the launch customer in May, when it signed to have WheelTug installed in 100 of its A320 family.