A Green Taxi aircraft?

When you see a headline about a Green Taxi - you think about hybrid cars, right? 

Well perhaps you will soon think about hybrid airplanes! 

Honeywell has announced a system that will allow airplanes to taxi to the runway without firing up their main engines. 

The idea is to install electric motors on the aircraft's wheels and use the airplane's APU (auxiliary power unit) to supply the electricity to the motors. 

The new electric green taxiing system is expected to save up to 4% of the aircraft industry's total fuel consumption while providing green benefits that significantly reduce the carbon and other emissions produced by taxiing at ground level.

They expect it to be installed on new aircraft and retrofitted on to existing planes, beginning in 2016. Taxiing burns a significant amount of fuel. Current industry analysis indicates that the world's short-haul aircraft consume 5 million tons of fuel per year during taxi operations. 

Aircraft equipped with this new electric green taxiing system should be able to "pushback and go" more quickly as well thus reducing gate and tarmac congestion, improving on time departure performance and saving valuable time on the ground. Fuel savings are not the only operational cost this aircraft electric green taxiing system will address. The system will eliminate the need for tugging and associated equipment costs, and it reduces both brake wear and taxes based on carbon emissions.  

These costs are especially problematic for airlines with high percentages of short-haul operations because ground taxiing is a greater percentage of total aircraft use. That makes airline profit margins for short-haul aircraft more sensitive to these expenses. Fuel-saving technology such as this electric green taxiing system can significantly improve the airline operator's bottom line. Honeywell and Safran intend to focus their joint venture on narrow-body-sized aircraft, which are more likely to be used for short-range flights. 

The aircraft electric green taxiing system works by using the aircraft's APU to provide power to specialized motors near the main landing gear wheels. Unique power electronics and system controllers allow the pilot to control the speed, brakes and direction of the aircraft throughout ground transportation.