Airside Winter 2019

HYDRO Systems unveils all-new battery-powered pushback

On the HYDRO Systems stand at inter airport was its all-new emover electric tug. The first and only prototype of this all-new, innovative aircraft tug was available for viewing at the Biberach, Germany-headquartered company’s outdoor booth

The emover is a lithium-ion battery-powered tug that will be able to push/pull aircraft of weights of up to 600 tonnes. This will allow it to handle all types of narrowbody and widebody aircraft, from E190s right up to A380 super jumbos.

According to the company, this “unrivalled universality of aircraft types” that the tug can handle will be one of its “key success factors”. The emover’s flexibility means that any ground service provider needs access to only a relatively small fleet of units, while also allowing each tug to reach any aircraft requiring pushback quickly, given that the units are not restricted to particular aircraft types.

The capability of handling such a wide range of aircraft types, right up to the A380, is pretty much unique for a solely battery-powered pushback tug.

Its low-profile design gives the emover a sleek appearance and also enables it to get under low-slung aircraft such as the B737. Its six driving and steerable wheels give it excellent manoeuvrability. In fact, the machine can rotate through 180 degrees, allowing it to make extremely tight manoeuvres in a hangar and so maximise the space within the facility.

The emover has a top speed of 23km/h, while its cabin has seating for the driver and up to two others.

It offers automated change of tow heads (up to eight) depending on the aircraft to be handled, with accurate measurement of push, pull and torque forces available to the operator. A 2D scanner assesses the aircraft type as the emover moves up to the aircraft, and the unit’s control system then automatically selects the appropriate aeroplane-specific force profile for the pull. This minimises the force needed to push/pull an aircraft, saving energy as a result.

The tug incorporates the latest in safety features, including automated positioning to the aircraft and a collision warning system supported by a bird’s eye view camera system for all-round visibility.

With cabin, it measures 10.35m by 4.85m by 1.55m and weighs between 52 and 60 tonnes. Its battery – which takes an hour to charge – offers 195kWh capacity.

A future option for customers could be a remote-controlled emover variant that would have no need for an operator’s cabin at all, further saving on space and operating costs.

Gap in the market

HYDRO was founded back in 1965 in Biberach, producing axle and tripod jacks. Since then its footprint in the aviation industry has grown. While expanding the product portfolio has always been a key element of the corporate strategy, the emphasis has remained on GSE and airframe and engine tooling solutions.

So what inspired HYDRO to branch out into the aircraft tug market, and in particular the fast-changing world of battery-powered tow tugs? Simply put, the company spied an opportunity in the market, recalls head of innovation management Ulrich Ockenfuss.

While most of the tugs operating at airports around the world remain diesel-powered, the trend is very much towards battery-powered variants and that process is only likely to speed up, he notes. Airports around the globe are now installing the necessary charging infrastructure, so HYDRO took the decision to develop an emissions-free, low-maintenance and no-fuel-cost electric tug.

The resulting emover has been in development since early 2017, with detailed engineering work on the vehicle having taken up a little less than two years of the period since. The one prototype on the stand at inter airport is soon to be joined by a second (possibly ready by February or March next year), while the current unit was to go into a rigorous internal validation programme straight after the show.

That programme will include battery tests and vehicle driving and pulling trials, and is expected to last for perhaps four or five months. Practical testing of load pulling will begin at a former NATO airbase in Germany called Lahr, with a phased process leading up to full aircraft towing, which is expected to take place at a Fraport airport next year – the German airport operator is a key partner in the emover development programme, and the vehicle at the HYDRO booth at inter airport carried the Fraport logo.

Certification with Boeing and Airbus will also form a key part of the development process, with HYDRO expecting the necessary certification to be granted by about October next year. And the hope is that the emover will be ready for commercial deployment by the spring of 2021.