This is a recording of a recent live teleclass I did with thousands of kids from all over the world. I’ve included it here so you can participate and learn, too!

Soar, zoom, fly, twirl, and gyrate with these amazing hands-on classes which investigate the world of flight. Students created flying contraptions from paper airplanes and hangliders to kites! Topics we will cover include: air pressure, flight dynamics, and Bernoulli’s principle.

Materials:

• 5 sheets of 8.5×11” paper
• 2 index cards
• 2 straws
• 2 small paper clips
• Scissors, tape
• Optional: ping pong ball and a small funnel

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# Key Concepts

While the kids are playing with the experiments see if you can get them to notice these important ideas. When they can explain these concepts back to you (in their own words or with demonstrations), you’ll know that they’ve mastered the lesson.

1. Air pressure is all around us. Air pushes downward and creates pressure on all things.
2. Air pressure changes all the time.
3. Higher pressure always pushes.
4. The faster air travels over a surface, the less time it has to push down on that surface and create pressure. Fast moving air creates low pressure regions. (Bernoulli’s Law).
5. The four fundamental forces on an airplane are lift, weight, thrust, and drag.

# What’s Going On?

There’s air surrounding us everywhere, all at the same pressure of 14.7 pounds per square inch (psi). You feel the same force on your skin whether you’re on the ceiling or the floor, under the bed or in the shower.

An interesting thing happens when you change a pocket of air pressure – things start to move. This difference in pressure causes movement that creates winds, tornadoes, airplanes to fly, and some of the experiments we’re about to do together.

An important thing to remember is that higher pressure always pushes stuff around. While lower pressure does not “pull,” we think of higher pressure as a “push”. The higher pressure inside a balloon pushes outward and keeps the balloon in a round shape.

Weird stuff happens with fast-moving air particles. When air moves quickly, it doesn’t have time to push on a nearby surface, such as an airplane wing. The air just zooms by, barely having time to touch the surface, so not much air weight gets put on the surface. Less weight means less force on the area. You can think of “pressure” as force on a given area or surface. Therefore, a less or lower pressure region occurs wherever there is fast air movement.

There’s a reason airplane wings are rounded on top and flat on the bottom. The rounded top wing surface makes the air rush by faster than if it were flat. When you put your thumb over the end of a gardening hose, the water comes out faster when you decrease the size of the opening. The same thing happens to the air above the wing: the wind rushing by the wing has less space now that the wing is curved, so it zips over the wing faster, and creates a lower pressure area than the air at the bottom of the wing.

The Wright brothers figured how to keep an airplane stable in flight by trying out a new idea, watching it carefully, and changing only one thing at a time to improve it. One of their biggest problems was finding a method for generating enough speed to get off the ground. They also took an airfoil (a fancy word for “airplane wing”), turned it sideways, and rotated it around quickly to produce the first real propeller that could generate an efficient amount of thrust to fly an aircraft.  Before the Wright brothers perfected the airfoil, people had been using the same “screw” design created by Archimedes in 250 BC.  This twist in the propeller was such a superior design that modern propellers are only 5% more efficient than those created a hundred years ago by the two brilliant Wright brothers.

When you’ve worked through most of the experiments ask your kids these questions and see how they do:

1. Higher pressure does which? (a) pushes (b) pulls (c) decreases temperature (d) meows (e) causes winds, storms, and airplanes to fly
2. The tips on the edge of a paper airplane wing provide more lift by: (a) flapping a lot
(b) destroying wingtip vortices that kill lift (c) getting stuck in a tree more easily (d) decreasing speed
3. In the ping pong ball and funnel experiment, the ball stayed in the funnel was because:         (a) you couldn’t blow hard enough (b) you glued it into the funnel (c) the ball had a hole in it  (d) the fast blowing caused a low-pressure region around the ball, causing the surrounding atmospheric pressure to be a higher pressure, thus pushing the ball into the funnel
4. If your plane takes a nose dive, you should try (a) changing the elevators by pinching the edges (b) change the dihedral angle (c) change how you throw it (d) all of the above
5. What are the four forces that act on every airplane in flight?
6. Draw a quick sketch of your plane viewed from the front with a positive dihedral.
7. If you were designing your own “Flying Paper Machine Kit”, what would be inside the box?
8. What’s the one thing you need to remember about higher pressure?
9. What keep an airplane from falling?
10. Where is the low pressure area on an airplane wing?

1 (a, e) 2 (b) 3 (d) 4 (d) 5 (lift, weight, thrust, drag) 8 (higher pressure pushes) 9 (lift) 10 (top surface)

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### 28 Responses to “Special Science Teleclass: Flying Machines”

1. Tania Harris says:

cool

2. Which experiments are you looking for?

3. Gail Fripp says:

How do you get to the page with all the experiments.
I am having trouble getting around the website =(

4. They do fall at the same rate on a planet or moon without an atmosphere. It’s because of the air resistance that one falls more slowly than the other. If you take a sheet of paper and wad it up, and let it fall at the same time as another sheet of paper, the waded up paper falls faster than the sheet. They both weigh the same, but the air needs to in effect “get out of the way” a lot more with the larger sheet needs so it falls more slowly.

5. Jackie Quarles says:

We are still having a hard time understanding why a feather doesn’t fall at the same rate as a brick if gravity is pulling on both. You mentioned in the last section that air pressure is the reason…but after studying this, we are still not quite sure we understand…could you give a little more explanation as to how to explain this? Thank you!

6. Sure thing! Just click on the link on the upper right that says “Experiments” and you’ll find not just three but nearly a dozen different ones to make! 🙂

7. Anonymous says:

Hi Aurora,
We watched the video of your Flight class and at the end, when you are about to show how to make 3 different types of paper airplanes the video finishes. My girls were all ready to make them! Help!

8. It depends on the size, shape and weight of the object, in addition to how you are getting it to fly (are there wings?)

9. Cindy Smith says:

How much force do you need to get an object in flight?

10. Hmmm.. sounds like something might be mixed up with your account. Tonya will connect with you and get you rolling!

11. jlpurl2 says:

Today’s date is 6/2/15 10:31am central time. I am getting a message that says I don’t have access to all of the content & you will release it at a later date. We are trying to start the kite & flying experiments you have already opened to us. How can I get access to the rest of the content & when will that be available. My kids are excited to get started!

12. I’ll have my team contact you right away!

13. Cailon Moreau says:

It says i don’t have access to this section is that a problem, or is that just me?;)

14. Sorry for the confusion! e-Camp is available June through August. 🙂

15. Laura Maloney says:

i can’t seem to get to the e science camp ! Help please!

16. Yes – that’s the other part! There’s not a lot of lift generated by this design – it’s just really streamlined to slip through the air. 🙂

17. Christy Bravo says:

The paper circles are also going through the air to,is that the other part?

18. That’s part of it… what else is going through the air besides the straw?

19. Christy Bravo says:

I think that the air going through the tubes makes it fly straight.If thats not right tell me what is.

20. Good question! What do YOU think? 🙂

21. Christy Bravo says:

why does the airplane with the tubes fly straight

22. Sorry about that… this teleclass accompanies another section of e-Science also that includes the Flight Lab, which is currently in the e-Camp section that is released in summer. Let me see if I can help… I’ve rewritten the exercise questions so they match the teleclass. 🙂

23. Tim Kubo says:

Hi Aurora,
The experiments for questions 4, 8, 9, 10, and 11 are not in the video. Hw are you supposed to know the answers

24. There were many different inventors that worked on this at the turn of the century and for hundreds of years before that. You might check your local library to learn more about great inventors during the early 1900s!

25. Dan Archer says:

who made the first plane that did not work

26. Hit PAUSE and then go back a bit and replay it again as many times as you need to. 🙂

27. Katie Barr says:

I got lost at making the airplane after you fold it in half. What do I do?

28. Anne says:

Hi Aurora,
I love the materials I have seen so far…thanks for putting together an
awesome website! To get ready to learn about flying machines, I thought it
would be fun to figure out how much air pressure my grandkids actually
experience living here at sea level in the Bay Area. It takes only simple
math to determine body surface area, and from that to calculate the total
pressure (okay, I did use a conversion calculator to convert the metric
surface area into inches). We learned that my grandkids (who are very close
in size) have about 17,537 pounds of air pressure pushing on them at all
times. Wow! That was an eye opener.
Best,
Anne