### Bird Watch

Do you know which birds are regular visitors where you live?

### Investigating Epidemics

Simple models which help us to investigate how epidemics grow and die out.

# Helicopters

## Helicopters

With thanks to Class 6K
Mayfield Primary School, Cambridgeshire
for letting me observe their science lesson.

Watch the video below to see one way of making a simple helicopter.

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Imagine you have been asked to design a helicopter to drop supplies to people in a remote disaster area. A controlled descent and soft landing is essential - too fast might damage the load and too slow might blow off course!

Here is a template for one possible helicopter (Word, pdf).
How would you decide on the best possible helicopter design?

You will need to decide the height from which you will drop the helicopter, and the load it will carry.

Here are some issues to consider in your search for the best helicopter:

• number, shape and design of wings
• speed of descent
• choice of materials
• cost of materials
• wastage
• choice of colour

Thanks to Jim Flood, former staff tutor in Technology at the Open University, for the design of the helicopter template.

### Why work on this activity?

This activity offers an opportunity to combine skills from mathematics, science and technology. Students are required to consider different options, experiment with variables, keep records of results, make predictions, analyse and present data, develop convincing arguments, work collaboratively, and work within constraints.

### Possible approach

Using this template, give everyone in the class the chance to make a helicopter and try it out. You may wish to show the video first.

Next, introduce the challenge to design the "best" helicopter. You might like to set the parameters for "best" yourself, or to have a class discussion on suitable criteria for judging helicopters. This should include a decision on the height from which the helicopter will be dropped, as well as the load it will carry.

Arrange students in small groups, and make it clear that at the end of the time available they will need to present to the rest of the class their helicopter with supporting evidence of its merits.

To round off the activity, allow plenty of time for each group to present their design and encourage the rest of the class to give positive feedback and also to comment on how (un)convinced they are by the evidence presented in the "sales pitch".

Equipment:

• helicopter template  (perhaps printed on thin card)
• paper and card of different thicknesses
• paper clips
• scissors
• ruler
• sharp pencil

### Key questions

What's the maximum number of paper clips you can add while still having a safe descent and landing?
Does the helicopter always land in the same place?
Can you make it fly to particular places?
Does it always rotate in the same direction?

### Possible extension

This activity could be extended in a couple of ways: firstly by introducing more demanding success criteria for the helicopter, or secondly by expecting a more rigorous analysis of the results from the tests done with different helicopters.

### Possible support

Remind students to keep everything constant except that which they are testing, and to perform each experiment more than once and take average results.

Guidance could be offered on the sorts of changes to make, for example, keeping the helicopter in the same proportions, but gradually increasing its overall size, or keeping the width of the wings and the body constant, and gradually increasing the length of the wings and body.