Text only explanations for the video

Below is the text explanation that corresponds to the numbers in the video.

I did not invent walkalong gliding (AKA air-surfing)— the activity of mysteriously levitating gliders with deflected relative wind. The concept has been around for a generation, yet it remains almost unknown. There is a reason for that. Although walkalong gliders are not difficult to make and fly, getting people through the FIRST STEP has been difficult.

My obsession for the last 5 years has been to get my students flying as a hands-on science activity. We started with paper gliders but switched to very thin foam, recycled from packaging, which has superior strength to weight ratios. Then we found foam that was even lighter. Finally, we have gliders so efficient and slow-flying that people can be flying within minutes. Almost all the people in the video had not known how to fly 5 minutes earlier.

The best way to start is to buy a box of foam that also has a couple of ready-to-fly gliders. It’s not only that you can start flying very quickly; knowing how the gliders are made and flown then makes it easier to make your own. The proceeds from the sales go to a no-profit Physics Factory.

1. The numbers correspond to the numbers at the top of the screen in the video.
2. The easiest way to start out is buy a box of foam which includes some ready-to-fly gliders. Open carefully and save the box for protective storage and transport.
3. This is special very low-density foam which is unbelievably lightweight. It is recycled, originally used to cushion imported furniture. We hotwire cut it on a homemade robotic CNC machine to perfect half millimeter slices. It is also very delicate to handle. You can wreck it without trying.
4. Although the gliders have been tested and are ready-to-fly, we have to bend the front wire weight flat for shipping. Just bend it 90 degrees, but be very gentle as you handle the glider. If you don’t bend it forward, the glider will probably stall rather than fly forward. If the glider still seems to stall too much, you can bend it forward even more. This shifts the “center of gravity” (balance point) forward in the glider. Opposite, if the glider dives, then you can remedy diving by bending the wire backward, which shifts the center of gravity backward.
5. For launching, make sure that you are holding the glider right side up: the wire bends down. There is a little downward bend at the front of the wing. This front wing bend is called camber and it creates an airfoil shape for more efficient flying. At the back of the wing are 2 flaps that bend 45 degrees up, called elevons. They keep the glider from diving.
   You hold the glider gently from the back. Notice that there is a thumb and finger below, and just one finger above the glider. This keeps the glider wings slanting up just a little. This upward slant of the wings is called “dihedral”, which all airplanes have for better stability.
   Caution: some people unconsciously hold the glider in a way that makes the wings droop down (anhedral). If the glider wings do not spring back to dihedral, then the glider will not fly.
6. You have a place with no wind. The conditions for flying outside are rare, perhaps at dawn, dusk or overcast days. If you feel ANY wind on your face, it’s too much to fly.
   Notice that the gliders fly so slowly that you do not need a large indoor space; a small room works well. Later you will see that you can turn the gliders.
   Notice that the pilots are not swishing the boards or making fast, jerky movements. Keep it smooth and steady.
7. A common problem for beginners is that they forget to tilt the board back, which results in the glider not flying. Start with a board angle of 45 degrees, then experiment. But many beginners unconsciously flatten the board horizontally like a floor.
   It might help to understand how the gliders fly. By tilting the board and walking, you deflect the air that you walk into—up and over the board, in a continuous wave. If you can balance the glider on that upward wave of air, then you are actually surfing the glider on the wave of air. That’s why I call walkalong flight “air-surfing”. Of course, the wave of air is invisible, so it’s tricky, almost like, “Use the force!”
   I can walk alongside people with both of us holding the board, so they get a feel for flying. I can teach people to fly in a couple of minutes. But you, brave soul, don’t have anyone to walk beside you and give you a feel for flying; hence, the video and written instructions. I expect that it will be more difficult for you. Please let me know.
   how it goes and any ways that learning might be made easier.
8. Another common problem for beginners is that they let the glider get too far ahead of them and low on the board. Then the glider is intercepting less updraft, so it flies less efficiently, so you have to walk much faster just to keep it up. If the glider gets low enough on the board, it is actually forced DOWN! Try to keep the glider even with the top of the board by moving faster and keeping up with it.
   Less common, but possible, is to have the glider too HIGH on the board. In this case, the glider always tries to turn to the left or right. In extreme cases the glider will blow right over the top of the board. Again, start with keeping the glider even with the top of the board.
9. It is common for beginners to have trouble with maintaining altitude. But they can gain altitude by getting the to edge of the board very close to the glider. Normally the glider would blow over the top, but raising the board prevents that.
10. At first, it seems that the glider capriciously decides whether to turn left, right or go straight. But you, the pilot, can push the glider whichever way you wish. Aim the corner of the board toward the corner of the glider. As the board gets very close, the air being pushed in front of the board pushes one side of the glider, making it turn.
11. If the glider does not turn, here are a few tips: First, get “pushy” as if the corner of the board will actually hit the glider. Just as many people do not get close enough with the board when flying, they also do not get close enough when turning. Second, “bank” the angle of the board. Turning is the only time that having the glider a little low on the board is good. Third, do not ever back the board up. If you do, it will suck the glider backward. Notice that when I seem to punch at the glider with the board (a good way to practice turning) I never pull the board backward—I just stop. Finally, when the whether is cool and very dry, static electrical cling can be a problem. If the glider actually sticks to the board when you get close so that you can turn, you have a static cling problem. To prevent it, try not to let the board rub against your clothing. If it happens, you can minimize it by wiping the board with a damp cloth. Do not get the glider wet, though, because it will change the weight.
    Notice that I can make very sharp turns. When you make a very tight 180-degree turn, the glider might encounter turbulence from your body moving through the air. See if you can work through the turbulence—a sign that you are getting really good at flying.
12. When you become skilled at flying with a board, try flying with your hands. That really looks like magic! There is much less air-deflecting area from hands, so it is even more important to get the position of hands relative to glider exactly right. Look at the freeze-frame and note that my fingers are just below the trailing edge of the glider. If you get just a little too far behind, the glider dives down. If you get just a little too far ahead, the glider stalls. I spread my fingers out slightly.
    I find that bending the wire forward makes the glider fly a little faster—better for hands-only flight, I think.
13. Turning with hands-only flight is a little different than turning with a board. I shift my hands slightly the opposite way that I want the glider to turn.
14. Younger people with smaller hands show great ingenuity for getting enough lift. The young man pushes air not just with his hands—which also make steering easier– but also with his whole body. He still needs his hands for control. Flying close to your head can also assist with lift.
15. What else can we do with walkalong flight? Landing on a short runway? Going through an obstacle course? Aerial dogfights? Here are some links of people doing interesting things with walkalong flight.
    Michael Thompson and David Aronstein dogfighting
    Dog fighting
    A relay race and an obstacle course
16. I do work from time to time with my friend Erik Herman, who conducts science outreach at Cornell University.
    He gave a group of friends a tour of the enormous former particle accelerator there, which is now the Cornell High Energy Synchrotron Source (CHESS). Wayne, who later gave us rides in his ultra-light airplane and who studies bird migration (and was a consultant for the movie Fly Away Home) flew a glider on the tour. At one point, he was able to fly the glider without moving. Usually we have to walk through still air, which creates “relative wind” (also called apparent wind) that goes up and over the board. But in this facility, the air from the ventilation system provides just enough gentle wind to keep gliders up. This is very similar to the way people-carrying hang gliders stay up using “ridge lift”.
    It is usually impossible to fly outside because of too much wind, but sometimes there is just a very slight movement of air that allows you to do this trick outside.
17. Taking off from the board is fun. It’s a bit challenging to get the right balance of tilting the board from horizontal toward vertical, with moving forward. If there is any static cling, it is impossible. The glider has to be tilted up a little on the board so air can get under and lift. You might have to bend the wire so it is shorter and strong enough to hold the front of the glider up.
18. 1The most advanced air-surfing is showing other people how to do it. Just because you had to learn it the hard way—by yourself—doesn’t mean that people around you should have to. Whenever I go to out and about, I always take some gliders along and show people how to do it.
    There are too many things to remember when beginning. So the beginner and I both hold onto the board. I launch and tell them to let me control the board while they get a feel for flying. We fly straight, then turn a few times, then we gain altitude a couple of times. Then I let go and they take over. Many of the people in the video were strangers whom I had just met less than 5 minutes earlier and shown how to fly.
    On this page are some more thoughts about teaching groups of people to fly.
19. The beautiful music—“Willow Girl”, “The Field in the Forest” & “The Windy Hemlock”–is by the trio Crowfoot.
    They are perhaps best known as a great contra dance band and you can see a spectacular example here.
    It’s been an honor for me to be able to use Crowfoot’s music on this video. It’s a privilege for all of us to support the artists who create the music that we love, by buying the music.
    I discovered the Crowfoot and other great groups at IMTFolk: The Institute of Musical Traditions. It’s a non-profit and obviously a labor of love. They put on great concerts in Maryland and put some tracks of the concerts on their website.
    Here is the original Crowfoot video.
    Here is another example of something that’s so good; and where else are you going to experience this? He plays and sings at about 5:50. How can these videos not have millions of views?
    More great music that I discovered on YouTube on my music playlist