How does the London Eye work?

Over 20 years since this giant city-centre wheel opened: jump aboard and explore its past

(Image source: Pixabay)

For 20 years, one large eye has watched over the antics of the UK’s capital city, attracting 3.5 million customers every year. But how was the London Eye designed?

In 1993 a competition was launched for architects and designers to create a suitable landmark to commemorate the upcoming turn of the millennium. No entry was ever chosen, but that didn’t stop husband and wife David Marks and Julia Barfield from presenting their entry to city planners anyway. Their idea was the ‘Millennium Wheel’, which would later be renamed the ‘London Eye’.

As key parts in this modernised version of a traditional Ferris wheel, the passenger capsules are a standout feature. These pods allow passengers to be completely contained, instead of the usual open-air gondolas. As a large open space with minimal seating, the experience inside aims to create a feeling of freedom, allowing people to explore the views from unlimited angles.

The original design incorporated 60 pods- symbolic of the minutes on a clock face – but in practice this proved too many, as packing them closely together limited their viewing range. Today, 32 pods can be counted around the wheel, equalling the number of boroughs in London.

This unique piece of architecture was assembled by specialists all across Europe: the main structure was built in the Netherlands, the cables in Italy, the spindle in the Czech Republic, the rim bearings in Germany and the capsules in a ski resort in France. The ovoid capsules they created house up to 800 people at a time and are constantly rotating every day, reminding all of the turning of the millennium in a city that never stops

(Image source: Pixabay)

How does the wheel turn?

The wheel only turns at 26 centimetres a second, meaning a complete rotation takes half an hour. Moving slightly faster than a sprinting tortoise, there is plenty of time to take in London’s scenery. It also enables customers to step on and off the capsules while the wheel is still in motion. When entering your allocated capsule, the colossal structure is moving using some of the same equipment that lorries use – tyres. The lorry tyres rotate with the help of hydraulic motors, which connect to the wheel’s rim. These power units operate eight pairs of tyres, acting as friction rollers. They push the wheel’s frame through the system in one direction, causing the entire Eye to spin.

This article was originally published in How It Works issue 135, written by Ailsa Harvey 

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