Smooth operators: a foursome of city cranes

Four Tadano AC 45 City cranes lifting the big one, a Contest 63 CS, worth around €4 million. Photo: Allison Transmission

A set of specific challenges has to be overcome by crane owner Wasel when it helps each year to set up a leading maritime trade fair.

Boot 2025 in Düsseldorf, Germany, had 1,500 exhibitors, many of which needed their expensive luxury yachts manoeuvred and lifted into position inside the exhibition halls prior to the January show.

This year Wasel deployed four of its 45 tonne capacity Tadano AC 45 city class cranes, often lifting in pairs and even all four of them together.

Space and headroom is limited inside the exhibition halls so the cranes need to be easily and precisely manoeuvred. Compact dimensions are important. The three axle AC 45 is 8.68 metres long overall, 2.55 metres wide and its height for road travel is 3.16 metres.

Wasel supplied four of its Tadano AC 45 City cranes. Photo: Allison Transmission

Four crane lifts

When the boats arrive on low loader trailers pulled by heavy haul tractors they need to be lifted off and staged on temporary supports. So-called Quadro lifts, where four cranes are used to lift a boat synchronously, are especially tricky. After lifting them they then have to be placed with millimetre precision.

An impressive example of this was lifting the Contest 49 CS, a 16.10 metre (53 foot) Dutch yacht weighing 21 tonnes. With boats arriving all the time the show set up was in full swing. A signaller directed the truck carrying the Contest 49 CS into Hall 16. The four AC 45s were positioned ready to for the lift. Space was limited with just 200 mm separating it from the next boat. With the crane up and off the trailer, the truck drove out and the cranes lowered the boat onto its waiting supports.

“Sometimes it’s only a matter of millimetres,” said crane driver Dieter Morgenfrüh, who has been working at the Boot show for 20 years. “Thanks to the Allison transmission, we have full control at all times. Especially in stressful situations, this is a significant advantage. On construction sites and particularly in exhibition halls, I can’t think of anything better than a torque converter transmission. Manoeuvring is much easier and, most importantly, the smooth start-up means there is no swinging and swaying on the hook.”

Also listed for hoisting was the Contest 49’s larger sibling, the 20.54 metre Contest 63 CS, worth around €4 million.

A yacht arrives in Düsseldorf for the annual maritime show. Photo: Allison Transmission

Making it work

Power for the AC 45 City is from a 260 kW (349 hp) in-line six-cylinder OM 936 diesel engine from MTU. Its fully automatic gearbox is an Allison 3500 Specialty Series (SP). This helps the 34 tonne crane’s manoeuvrability in tight spaces.

“The unique qualities of this crane are evident when working indoors. And here at the Boot, it’s even more of a challenge, because every little scratch on a yacht worth millions of euros incurs huge costs. Absolute precision is required,” said Gunnar Filges, Wasel branch manager. “We have four of these AC 45 City cranes in our fleet especially for this kind of work. Thanks to the torque converter transmission they are ideal for this application.”

A fully automatic transmission with a torque converter means the crane can start to move smoothly without jerking, even under heavy load. Even with careful clutch control a manual or automated manual transmission can induce load oscillation caused by interrupting traction when changing gear. An automatic transmission has permanent power transmission which, in addition to smooth crane operation in pick and carry, also makes for a more comfortable journey on the road.

On site where activity includes repeatedly starting off from stationary under load and on inclines or rough ground puts great strain on a standard dry plate clutch, either manually operated or automated, to the point where they can overheat and even burn out.

The Allison 3500 SP automatic transmission with torque converter is used in the Tadano AC 45 City class crane. Photo: Allison Transmission

Smooth torque

“The Tadano City cranes with Allison fully automatic transmission are predestined for working inside buildings or in narrow streets but we also use them for standard construction site projects. And that’s what makes these cranes so special. They are compact, easy to operate, quick to set up and incredibly versatile,” said Gunnar Filges. “We have been operating these cranes for over 20 years, first the predecessor model AC 40 and now the four AC 45s, and I have to say they pay for themselves.”

Mainz-based Allison distributor DGS Diesel- und Getriebeservice is responsible for sales and OEM support for the Tadano City cranes. Andreas Wolf, DGS sales engineer, commented, “The AC 45 City cranes are the only ones in their class that have a fully automatic transmission and consequently offer the best driving performance on site. The hydrodynamic torque converter facilitates smooth but also swift manoeuvring – a significant advantage over semi-automatic transmission solutions.”

Wasel is a leading crane-owning company, holding 29th place in the 2024 IC100 ranking of the world’s largest crane fleets. The Wasel fleet includes more than 150 wheeled and crawler mobile cranes. It also has a fleet of more than 400 tower cranes, putting it in 21st place in the world in that sector, according to the IC Tower Index ranking.

There are 400 employees at 11 depots in Germany’s Rhine-Ruhr area. In mid-2021 Wasel became part of the Hagedorn Group based in Gütersloh. Hagedorn revitalises power plant and industrial sites and is one of the world’s largest demolition companies.

See a video of the four crane boat lift.