The European Aviation Safety Agency and the Civil Aviation Authority of Israel have issued a supplementary type certificate (STC) for the TaxiBot aircraft towing system developed by Israel Aerospace Industries (IAI) in partnership with France’s TLD and Lufthansa LEOS. Plans call for the semi-robotic, pilot-controlled system to begin commercial operations with Lufthansa at Germany’s Frankfurt Airport by the end of November.

The initial STC—the first for a system of this type, according to IAI—covers use of TaxiBot with Boeing 737s under FAR 25 rules. Unlike a standard no technical objection (NTO) approval issued by the airframer, the STC covers the use of the equipment for all phases of push back and taxiing to and from the runway. Airbus expects soon to issue an extended NTO for its A320 fleet that would cover the same scope of operations.

Trials of TaxiBot have proven its ability to taxi a fully loaded 737 at 23 knots, which IAI claims is the fastest speed achieved by a taxiing system to date. Rival systems are under development by a Honeywell-Safran partnership and by WheelTug.

IAI claims TaxiBot offers significant savings in fuel consumption and engine emissions. According to the company, a 737 or A320 burns about one metric ton of fuel (1,250 liters) in a typical 17-minute taxi operation. By comparison, the TaxiBot only consumes around 25 to 30 liters for the same operation. An aircraft taxiing under the power of its own engines would emit around 7,040 pounds of carbon dioxide, compared with less than 132 pounds with the TaxiBot.

The pilot retains full control of taxiing, operating the TaxiBot via the aircraft’s tiller and brake pedals, and the system requires no modification to the aircraft. Crews perform coupling and decoupling of the TaxiBot on the taxiway, close to the runway.

In trials conducted by Lufthansa, the airline found that it achieved savings of 37 percent in terms of the time taken to get in and out of airport gates. According to IAI TaxiBot project director Ran Braier, the equipment also reduces the exposure of aircraft engines to foreign-object damage during the taxi process.

IAI has yet to announce a base price for the TaxiBot but said that airlines will achieve a return on their investment in less than 18 months as a result of fuel savings and reduced cost of operations.