Reach for the sky above Vienna

• What was needed: Energy chain series E4.1, chainflex cables
• Requirements: The cables must be guided safely and reliably at a height of 70 metres – in all weather conditions.
• Industry: Amusement rides
• Success for the customer: The chain links are checked every day and no problems have been detected so far.

Before the ride can even begin, Franz Taraba walks between the gondolas hanging just above the ground. The Prater Tower technician checks that the passengers’ safety belts are correctly fastened and secures the additional metal extender crossbar. Safety is paramount at the Prater Tower, as the ride is enormous: the tower is 117 metres high and the maximum flying height is 95 metres. The StarFlyer chain plane from Austrian manufacturer Funtime Industries reaches a maximum speed of 60 kilometres per hour, allowing visitors to fly over the roofs of the Prater and enjoy the Vienna skyline from the Danube Tower to the city centre. Even those who stay on the ground are captivated by the spectacular ride. At the latest when the gondolas start moving. First they are pulled up to a certain height, then the rotation begins. According to the laws of physics, passengers are carried outwards, the seats hanging from the taut steel chains that lead up to the tower. Anyone who decides to take a ride in the Prater Tower buys the adrenaline rush along with it. However, what very few people see is the technology that makes the fun of riding a chain plane possible in the first place: there is not much space in the tower, where a ladder with steel cables and other technical equipment leads up to lofty heights. A central component for smooth operation can be found in the outer scaffolding of the tower: there, inside a metal guide rail, is a hanging energy chain from Cologne-based motion plastics specialist igus.

When Funtime erected the tower in Vienna’s Prater park in 2010, the StarFlyer was a world first with unprecedented dimensions. Last but not least, the Guinness World Records certificate for the world’s highest chain carousel hangs in the arcades beneath the ride. Funtime has since installed more StarFlyers, some of them larger, around the world, including in Orlando and Texas in the United States. Thirty thousand screws were used in the construction in Vienna, and the foundation alone weighs 720 tonnes. To withstand the enormous loads at such heights, reliable interaction between man and technology is essential. Franz Taraba is out and about in the tower every day checking all the components. This is a matter of course for the operators of the Prater Tower, because it goes without saying that all visitors should have a safe ride. “We carry out a visual inspection of the tower every day,” explains Taraba. As a rule, there are no issues and the ride is ready for another day at the Prater. The fact that the technology works so reliably is down to the high quality of the materials used – such as the energy chain from igus.

During the construction of the tower over 13 years ago, an energy chain quickly became the choice for energy supply. The plastic components display their advantages in amusement park applications. They require a safe guide for the cables to protect them from damage. At the same time, the movement must be guaranteed at all times. Due to the prominent positioning and the great height, the components must be weatherproof. "The energy chain from igus runs like clockwork," says Robert Danhel, technology manager at the Prater Tower, with satisfaction. Thereby, the advantage of the energy chain is that it does not need to be lubricated. With its energy chains, plain bearings and other plastic innovations, igus relies on lubrication-free technology that offers completely new potential in practice. The Cologne-based company has decades of experience in the manufacture of energy chains for demanding applications, as can be seen in the Prater Tower. When building the tower, Funtime and igus developed a chain with crossbars every link of the E4.56 series, which has been working reliably since then. "We still have the same energy chain as on day one," says Danhel.

The energy chain has a travel of 80 metres and accompanies the gondolas at a speed of 2.2 metres per second on the way up. The suspension is located several metres above the ground so that flexible movement is possible. The chain contains the proven chainflex cables from igus, ensuring safe communication from the top to the very bottom. This is important, because the cables play a central role in the ride. With chainflex, igus has developed cables that are specially designed for use in the energy chain. igus offers 1,354 cable types for drive, data, bus, hybrid and control systems. The Prater Tower also benefits from this variety. In addition to the power supply, there are data cables, including for monitoring the metal safety brackets on the seats. "We have also had no problems with the chainflex cables so far," says Robert Danhel. An alternative to the energy chain in comparable applications would be the installation of a busbar system. However, Funtime quickly refrained from doing so. "Busbar systems are prone to problems with data transmission and weather resistance," explains the technology manager. The maintenance effort would therefore be much greater with a busbar system.