ISRAEL & IN FOCUS: Israel leads electric taxi push with Taxibot

Tel Aviv
This story is sourced from

Inside Israel’s aerospace and defence industry is a deep reservoir of technology cultivated for a single purpose: national survival. Adapting those skills and know-how in adjacent markets is an obvious business goal, but always fraught with risk.

Four years ago, Israel Aerospace Industries (IAI) teamed with Airbus to solve a problem for airlines on the ground.

The world’s airlines will face an estimated $7.7 billion bill annually by 2020 on fuel and engine repairs because aircraft have no means of propulsion on taxiways other than a set of jet engines far over-sized for the task.

Israel Aerospace Industries (IAI) is now leading one of at least four industry teams proposing competing ways to save fuel by keeping the jet engines turned off during most of the journey by taxiway before take-off.

The electric-powered Taxibot – developed by an IAI-led team – is expected to receive certification by the European Aviation Safety Agency (EASA) in the second quarter.

The product is tailor-made to capitalise on IAI’s experience as an aerospace-grade systems integrator with a deep background in autonomous vehicles.

It also presents an interesting test case. To leverage IAI’s expertise, the Taxibot must invent and sustain a new business model in a highly complex operating environment amid intense competition.

IAI’s approach on the Taxibot is emblematic of the company’s pragmatic philosophy on innovation.

The three major competitors – WheelTug, the Honeywell/Safran electric green taxiing system, and the L-3 Communications/Crane Aerospace GreenTaxi – focus on adding power systems to the aircraft.

The Taxibot takes the opposite approach and leaves the aircraft alone. Instead, it reinvents the humble aircraft tow tractor with a hybrid diesel-electric, semi-autonomous vehicle. Inside the Taxibot, two diesel engines generate power to drive electric motors on the wheels.

The ground vehicle connects to the nose landing gear of aircraft at the airport gate. Pushing back is the same as with a conventional towbarless tractor. A Taxibot driver manoeuvres the aircraft onto the apron. Normally, the tractor would disconnect from the landing gear and the pilot would start the jet engines to move onto the taxiway.

Instead the jet engines remain off and the Taxibot operator passes control of the ground vehicle to the flight deck, with the nose landing gear still clamped on.

The pilots then control the Taxibot with a nose-wheel tiller. If IAI’s control software works as hoped, the pilots won’t feel a noticeable difference between steering the nose wheel directly or through the Taxibot.

The pilot then steers with the Taxibot onto the taxiway, running at a top speed of up to 22kt (41km/h). The aircraft then taxis to a designated disconnection point. The taxibot declamps from the nose landing gear. In 10 years or more, the ground vehicle may be able to steer itself autonomously back to the airport gate. For the foreseeable future, however, the driver on the ground will remain inside the Taxibot even after the pilot takes control. Following disconnection with the aircraft, the ground driver will steer the Taxibot back to the gate.

The challenge now becomes how to sign on the first customer. Lufthansa spent several months demonstrating the Taxibot at the Frankfurt airport after-hours.

More recently, IAI officials presented a business case to the Port Authority of New York and New Jersey (PANYNJ), which manages John F Kennedy (JFK) International Airport.

In IAI’s proposal to JFK, the airport would be equipped with a fleet of 16 narrowbody Taxibot vehicles and nine widebody Taxibots. IAI assumed that the narrowbody Taxibots could service 79% of JFK’s traffic and the widebody vehicles would accommodate 75%, with the remainder using jet engine power to taxi during peak hours.

IAI estimates that each departure at JFK today costs $330 in fuel and ground handling expenses, as the average taxi time is 22.5min.

Based on those assumptions, the Taxibot fleet would reduce taxi time on jet engine power by 22min, reducing fuel departure costs per aircraft by $220.

In recent years, the PANYNJ invested more than $40 million on a project to create high-speed taxiways at JFK. Their goal was to shave 1.5-2min off the average taxi time at the airport. IAI’s offer to reduce the taxi time by 22min caught the airport’s interest.

“It’s very interesting during the discussion once we mentioned 22min of savings,” says IAI business development manager Eran Tamir. “The whole discussion turned because the economic viability was there, and now you just need to think about how to do it correctly.”

Implementing a Taxibot fleet at a major international airport is no simple task.

IAI officials acknowledge the problem of adapting the concept to the unique organisational and management structure of each airport – and even each terminal within the airports.

“There is not a typical airport. That is the problem,” says Oren Aviram, director of marketing of IAI’s Lahav division. “When we have looked to define what is a typical airport, we found out there are 100 typical airports.”

In the specific example of the JFK airport, the business case is even more complicated. The airport is subdivided into eight terminals, each of which independently manages ground handling and provisioning the gates with tow tractors.

For the terminals, the Taxibot presents a disruptive technology. All of the monetary savings created by reducing fuel consumption with the Taxibot are exclusive to the airlines. The airport receives credit for reducing greenhouse gas emissions, but also has to manage the impact on the existing and sometimes unionised ground handling workforce.

“It’s an issue,” Aviram says.

IAI has conceived a variety of ways to solve such problems. One possibility is establishing relationships with leasing companies that acquire Taxibots, then rent them to the airport ground handling staffs. The airlines calculate the annual savings, and share a certain percentage of the total with the service provider at the airport.

“We’re looking at different models today,” Aviram says. “They will find a way because there are economic forces behind it.”