
The Ferris Wheel is considered one of the greatest engineering wonders in the world. The first Ferris Wheel was created by Pittsburgh, Pennsylvania engineer, George W. Ferris, in 1893. The wheel is supported by two 140-foot steel towers and connected by a 45-foot axle — the largest single piece of forged steel ever made at that time.
— Fun and Exciting Facts About Engineering
Rotating rides – the path of motion is approximately a circle in a vertical plane. There are playground-scale rides, including most occupant-propelled rides as well as Ferris wheels and observation wheels.
Ferris Wheel – designed by George W. Ferris in 1893. It was designed to be the landmark of the World’s Fair in Chicago in 1893. The wheel is supported by two 140-foot steel towers. The towers are connected by a 45-foot axle, making the axle the largest single piece of forged steel made at that time. A Ferris wheel’s passenger cars hang within the wheel’s frame and are usually kept level by gravity.
Observation wheel – the passenger cars are not suspended from the wheel’s circumference but are mounted on its exterior. This requires them to be stabilised mechanically, making observation wheels a more technically complex form of the Ferris wheel.
The London Eye is currently the largest example of an observation wheel in the world. It stands 135 metres (443 feet) high on the western end of Jubilee Gardens, on the South Bank of the River Thames in London, England.
The wheel has 32 sealed passenger capsules. Each capsule is air-conditioned. Every individual capsule can hold up to 25 people. The slow rotation rate of the wheel means that passengers can embark and disembark the attraction without the wheel being stopped. A full rotation of the wheel takes 30 minutes.
What’s the problem?

Structurally the Eye resembles a huge spoked bicycle wheel. The wheel was constructed in sections which were floated up the river Thames on barges and assembled lying flat on pontoons. Once the wheel was complete it was raised into its upright position by cranes.
- Ask – The developers of the London Eye wanted to create a landmark structure and a memorable visitor experience. The space available was relatively small and on the edge of the river. What kind of structure could be developed for the purpose?
- Imagine – The weather in London is frequently rainy and cold. How could the design of a ferris wheel-like structure be modified to permit comfortable year-round operation?
- Design, Build – Thousands of passengers, including people in wheelchairs “fly” the London Eye each day. What are some of the design requirements to accommodate this number of riders? What special provisions are include to allow for access for people with disabilities?
- Improve – Although originally planned for opening in 2000 and operation for 5 years, the London Eye continues to be an important tourist attraction. What changes have been required during that time? What improvements are planned for new observation wheels planned and built since the London Eye was built?
That’s engineering
- Rotation – the movement of a body in such a way that the distance between a certain fixed point and any given point of that body remains constant. In 3-dimensional space, for a given rotational movement there is more than one fixed point: these form a line known as the axis of rotation. An object may allow rotation with respect to an attached other object by means of one or more hinges .
- Spin – The fixed point can be within the body, in which case the body is said to rotate upon itself.
- Gimbal – a device to control rotation. The device is usually a set of two or three rings mounted on axes at right angles so as to allow a Ferris wheel seat to remain suspended in a horizontal plane, regardless of the motion of its support.
Engineering ideas
- rotation, circumference, stabilize, vertical plane, gimbal, horizontal axis
Do It
Challenges for you to work on…
- find other examples of Ferris wheel and observation wheels.
News, updates
Learn more…
- The London Eye
- Gear-driven control for ferris wheel cars [Rock-O-Plane]
- Plural horizontal axes roundabout [Sky Wheel improvement]
- Amusement ride without hubs and spokes [Cyclotron or floorless Super Loops; hubless ferris wheel]
- Stationary track with gimbaled rider carriages