British Science Week: How to make sycamore helicopters

See the science behind the seeds that help sycamore trees reproduce

Before you begin…

If you’re under 18, make sure you have an adult with you.

Image credit: Future PLC/ © Illustrations by Ed Crooks

1. Create your shapes

 To get started you’ll first need to cut out different shapes from thick paper or card. Try to cut the shapes in a range of sizes, from around two to six centimetres — if you can use different coloured card for each one it will make it easier to tell them apart. When you throw them later, you’ll be able to test the different shapes to see which one works best. You can also write numbers on the shapes to help you tell them apart.

Image credit: Future PLC/ © Illustrations by Ed Crooks

2. Add the weight

Next, attach a paper clip to the narrow end of each shape. If you look at a real sycamore seed you’ll see that the seed itself is found in one end of the shape, with the rest of the structure dedicated to a fan-like blade that helps the side to float and fly. By adding weight to the thinner end of the shapes you’ve made you’re creating a similar structure, which should fly in the same way when you test it.

Image credit: Future PLC/ © Illustrations by Ed Crooks

3. Throw and test

You can throw your helicopters into the air or drop them from a high place like an upstairs window. Which shape is the most effective when they drop? Make a note and try to work out why different shapes work better than others. For some of the shapes you might need to bend the paper slightly to get the shape to spin well as it falls — this is just like real sycamore seeds, which have slightly curved blades.

In summary…

When a sycamore seed falls from a tree the air pushes up against the blades, bending them up. When air pushes upwards on the slanted blades the seed moves sideways, making it spin. If there is a big gust of wind the seed can be carried off to somewhere suitable for it to grow.

Disclaimer: Neither Future Publishing nor its employees can accept any liability for any adverse effects experienced during the course of carrying out these projects or at any time after. Always take care when handling potentially hazardous equipment or when working with electronics and follow the manufacturer’s instructions.

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