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Photo Tyler MacCready

Tyler MacCready received his Bachelor's degree studying philosophy at Yale University, and later studied geology at a variety of institutions including the University of Wyoming (MSc, 1993) and Monash University in Melbourne, Australia (PhD, 1998).

Since the mid-70's he has worked on several projects at AeroVironment, Inc. When he was 14, he was a test pilot for the human powered Gossamer Condor. Tyler has also worked on a 16' flying pteradactyl model (QN) and the Sunraycer solar car. He currently consults on a range of jobs, including geologic studies, developing devices to generate energy from ocean waves and instrumenting radio controlled airplanes to gather data from above. In his spare time he is engaged in "philosophical tinkering" using robotics and electronics to explore self-organizing systems.


Visit the Walkalong Glider web site to learn more about the glider and how it works.

For links to this scientist's home page and other related infomation please see our resources page

MacCready responds :

5.31.01 Camden Ray Smith asked:
Dear Mr.MacCready,
I'm a sixth grader and I have been interested in building planes and gliders since I was 5. I have not been able to get the information for how the glider stays aloft and how the air flows around the wing. If you have any information on that or any books to recommend, please let me know. Thank you for your help.

MacCready's response:
Because we are surrounded by air all the time, aerodynamics is great field to learn about through your own experimentation. In particular, paper airplanes can teach quite a bit. I have found that the key to rapid learning is rapid building, rapid crashing and rapid repairing. One of the nice things about paper airplanes or simple balsa or foam models is that you can test your ideas almost as soon as you think of them. Adding small tufts, such as pieces of thread or yarn, to a wing is very useful for seeing what the air is doing. And holding a wing out of a car window is a cheap way to simulate a wind tunnel.

When it comes to learning the technical principles of aerodynamics, I think it's worth mentioning that even among the experts there are some basic disagreements. Seemingly simple phrases like "airplanes stay up by pushing the air down" can cause heated debates. The behavior of the air is complex and often counterintuitive, and of course the substance itself is invisible. Thus, everyone pictures it differently, and it's not clear that anyone really understands it all. I am certain that the best designs for flying machines have not all been thought of yet, and the best secrets of flying creatures have not yet been revealed.

5.31.01 John asked:
What fields do you graze in to find your best creativity? What authors, artists, musicians, scientist and other inventors inspire you?

MacCready's response:
This is a tough question. There are many who inspire me toward lofty thoughts, but they do not inspire my creativity. I think my best creativity comes from pondering a problem for awhile and then being open to the moments of insight that come out of the blue. If I ever try to force creativity I get nowhere, but if I lay the groundwork for it by pondering and posing questions then there's no stopping the new ideas.

5.31.01 Billybob asked:
How did you make your walkalong glider, and what materials did you use?

MacCready's response:
The Walkalong Glider in its current configuration is made out of expanded polystyrene foam, cut an eighth of an inch thick and then thermally molded into the appropriate shape to make it stable enough to fly while still being maneuverable.

If you want to try making one yourself there are a variety of materials you can use. The only requirement is that the glider ends up light enough so that you can keep up with it when it flies. We have made Walkalong Gliders out of notebook paper and tape, balsa and tissue paper, fast food breakfast containers, foam plates, foam egg cartons and cardboard.

The real key is the trial and error testing and adjusting. Almost any flying thing will respond to some extent to the localized updraft your body produces as you walk forward. The challenge is to make a wing with sufficient performance and with an appropriate shape. One important aspect of the Walkalong Glider is that it is a flying wing. This configuration can be difficult to adjust for smooth, straight flight, but it is excellent for riding a small updraft. The wing shape is somewhat similar to a modern hang glider. In fact, we developed the idea as children while making paper airplanes that looked like hang gliders.

Making your own Walkalong Glider can be a lot of fun but it can also be frustrating. If it just isn't working out for you, or if you would like a working version to use as a starting point for improvements, you can go to where they are for sale.

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