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Paul MacCready and John Langford, "Human-Powered Flight: Perspectives on Processes and Potentials” - MIT 1998 Gardner Lecture (4/27/1998)

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[MUSIC PLAYING]

MODERATOR: The Gardner lecture given by the Department of Aeronautics and Astronautics at MIT. Lester Gardner was a friend of the department, was interested throughout his career in aeronautical engineering, and was instrumental in creating the Hunsaker professorship. He was mostly a publicist of the field of aerospace engineering as it's now called, and was the publisher for more than 10 years of aviation and aeronautical engineering, and was quite a noted contributor in his own right to aeronautical engineering in the middle of the century.

Today, for only the second time in the history of the lecture, we have two lecturers who will jointly, and in a somewhat coordinated fashion, give the lecture. This past week was the 10th anniversary of the flight of the Daedalus airplane, human powered airplane, from Crete to Santorini, perhaps recreating the mythical flight of Daedalus. Are you going to talk about the myth, John? You are. I won't take any more of John's ammunition.

And we thought it was an appropriate time to commemorate the entire history of human powered flight and asked two of the principals to come and be with us today to share their view of this history from the insider's view. I can recall, literally as a young man, that we had at MIT a series of I believe it was three symposia on low speed and motorless flight in the late '60s and early '70s, largely organized by the late Jim Nash Weber, and brought together at that time some of the leading figures and builders of human powered airplanes up to that point.

And my recollection of them was the last of them was in about 1974. Does anyone remember if that's-- '76. And that was still before any of the Kremer prizes had actually been won if my recollection serves me. Is that right? Yeah.

So we decided to make this, in some sense, a joint event, that there was today are organized by Mark Drela and Carolyn [? Thotusky, ?] the technical symposium on low speed and motorless flight, to bring together some of the ongoing technical efforts in that area and then followed by the lecture this afternoon.

Well, let me introduce very briefly our two lecturers. THey're, interestingly, both founders and chairmen of various small to medium size flight vehicle companies I guess you would say it.

Paul Macready is a figure who needs little introduction in the world of modern aerospace engineering. He's the founder and chairman of AeroVironment, Incorporated, a company that builds specialized aircraft with a particular emphasis on advanced electric power systems. He's a member of the National Academy and the American Academy of Arts and Sciences. And as you know, and probably will hear more about, is the father of the Gossamer family of lightweight human powered vehicles.

Jon Langford is the founder, president, and chairman of Aurora Flight Sciences, a company which specializes in flight vehicles specialized to the high altitude environment, and including the Perseus proof of concept vehicle. He was the program manager for the Daedalus project and the spark plug for several of the other previous human powered airplanes at MIT. And in the interim between two of those, left MIT where he received his degrees to go off and work on what became the F-117 stealth fighter at Lockheed Martin, or at that time the Lockheed Corporation.

So without further time delay, I'll introduce Paul MacCready who, as I understand it, will speak first.

[APPLAUSE]

MACCREADY: Thank you and good afternoon, friends of airplanes, human powered airplanes, challenges, and fun. This is a field that's been going on for a long time. There's been a huge amount written about it. In the short time we have this afternoon, there's no possible way of going over this huge history.

So one is referenced to a lot of books that exist. I've written up a version of my talk, a version that doesn't have much in the way of illustrations. I'm going to show lots of slides and videos here. So it'll be very different. But the written version does have a list of a lot of the publications that you can read that really give all the details on the facts of what happened in this field, how the field began, and events that have taken place until fairly recently.

Also, I will show towards the end, a video doing more with much less that shows Gossamer Condor and Gossamer Albatross very briefly, which you'll be hearing a lot about in the talk. But also it shows some of the things to which those have led fitting into a theme of the doing more with much less. And we give copies of that video to anybody who wants them. But I only have a couple of loose ones here.

But if any of you will sign your name over there or put a card in the little bowls on the far side of that table, apparently MIT has some way of magically seeing to it that you will receive one, because we'll just send them a bunch.

I wanted to not duplicate what's in the written literature but try and look a little broader perspectives. And the broadest perspective is start way back looking at what flight has meant to creatures on earth. Several hundred million years ago, it became obvious in evolutionary survival challenges that the air was a wonderful avenue to get up into away from the things that would eat you.

And instead of having to crawl over slimy things on the ground and fall rocks and so on, there is a nice, pure air to let you escape things, travel long distances, look for prey, et cetera. And there's such value in getting up into this added dimension in spite of all the difficulties associated with it where you have to have wings, and need light wing loadings.

And you're fragile and you have to have a good bit of energy and a lot of specialization. But the features are such that I think something like 3/4 of insects fly now. And obviously, other natural flyers-- birds, and bats, and pterosaurs were great success stories. And some of them still are.

To go through this very quickly, I want to start with the first slide, which shows the four arms-- one human, three belonging to other vertebrate creatures. And the three top ones fly. And because this ecological niche of flight requires the things that grow from little creatures' DNA requires either they flap something. They're flapping their arms.

And this slide shows that all of them have, including humans, have the same basic arm structure. So they started in the flight mode at different times so they accomplished it different ways. But if you follow all four of these back far enough, you come to certainly a common ancestor.

The top pterosaurs is very simple. And it's almost like a big hang glider. And the outer half of the wing spar is just the little finger that extended way out. And birds do it differently. Bats use their fingers as the control surfaces.

There are a lot of different insects, some old dragonflies I think were about 2 and 1/2 foot wingspan back in the old days. And even now, they are wonderful successes, nature's helicopters. Birds are similar. Hummingbirds are similar, nature's helicopters.

And the hummingbird looks very similar to the hawk moth, which occupies the same flight niche. They look the same but one's an insect. One's a bird.

The flyers that we're really in awe of are some of the more efficient birds. Here's an albatross. Just magnificent for going out over long distances over the ocean. And you'll notice very high wingspan. Looks almost like a sail plane. And essentially no tail. It can whip out a tail for some tight maneuvers, but most of the time, it does not use one.

Same is true of the frigate bird, which soars on very gentle up currents and convection over oceans, because it's using these weak thermals that are about a meter a second. It ends up as a superb low speed soarer with low sinking speed. The albatross using dynamic scoring is more like a bullet with wings. Goes a lot faster. Each one fitting their niche.

And then when you get over land, there are many other kinds of soaring creatures. And you start seeing ones that are very good at the low speed flight, maneuverability, all those feathers doing interesting and, we are beginning to learn, very efficient things in order to make flight work very well. And we just had a talk today on the way wings should join the body.

It turns out that resulted from a lot of advanced theory. And it turns out they look just like the vultures that have been around for 100 million years. So we're learning. We now can see bugs, birds, and bats fly. But we can't see the pterodactyls fly because they went extinct when the dinosaurs went extinct 65 million years ago.

As they started, and the pterosaurs, they were rhamphorhynchoids with tails like you see here, actually rather small creatures, more sparrowlike than the awesome size that you see. And then as they got larger, as time went on, the larger ones began having no tails. It turned out an ounce of brains used an active control seemed to be much better than adding an extra pound of tail on the creature. So modern ones just flew like ordinary creatures.

And this is a static display model of the largest creature that ever flew, the QN pterodactyl, of which we made a flying model to be in a movie called On The Wing showing the evolution of natural flight, evolution of technological flight. And there were no pterodactyls around to take pictures of so we made a replica, only an 18 foot one rather than 36 foot one, because we only were able to get up through the temperamental overweight adolescent size by the time the project was done. But it worked.

And in the flights, it crashed often but never when the IMAX cameras were pointed at it. Somehow it knew what its mission was. But to have this thing fly is just amazing. It has no tail. Trying to keep it pointing forwards like trying to shoot narrow with the feathered end forward. And it makes you appreciate nature. So wonderful on active control.

And those other birds that I showed you aren't using the tail very often. It uses active control. Humans are edging toward that. But most of our planes have regular tails. I've got a video that will show this flying if you start with number one.

[VIDEO PLAYBACK]

- On January 15 this year, in [INAUDIBLE], California, the modern day pterodactyl flew for the cameras in the Smithsonian's widescreen film On the Wing. A part of history we had not witnessed more than 65 million years ago was brought to life. Can you imagine?

The most important thing on this is that it serves as a symbol and catalyst against people's minds [INAUDIBLE]. What it's done for us is ensure [INAUDIBLE] appreciate the wonderful job mother nature does as a design.

Man will not [INAUDIBLE] something this large can be propelled by biological power, by muscles. But nature shows that it was. But it's the same fact [INAUDIBLE] wanted across the planet and realized we didn't discover [INAUDIBLE] geography. [INAUDIBLE] design an airplane. It just changed the world, because it got people's [INAUDIBLE], I hope this will be a little bit the same way. Okay.

MACCREADY: Nature has a lot of different ways of having flying things, showing you the four real fliers. But then seeds are made so they have pretty good aerodynamics. Pollen is distributed through the air. Spiders on spiderwebs can be transported hundreds of miles.

And there are many different kinds of flight. And there are flying fish. And many of you won't believe it but there are actually flying squid. And they fly in groups and fly very beautifully. Not very far.

All this is to emphasize that all energy of creatures on earth really comes from sun with a few exceptions and with different time constants. So solar power up here, you get instantly. Fossil fuel is stored energy of sunlight, maybe from many millions of years ago.

Up here using wind and heat to make thermals and sail planes fly. But also there's food for muscles, which is the energy that creatures use to get around. And so a hawk will start with this energy. And then we'll use a lot that comes from wind and the heating of the ground making thermals.

So I've shown a spectrum of flying things that go from practically no weight up to that giant pterosaur. And the pterosaur probably weighed, or pterodactyl QN and probably weighed 180 pounds at about a 36 foot wingspan. It was the only one of that species, the large one, found and I doubt that one found the biggest. And you look at some scaling laws. And there's no reason why they couldn't have had one, say, 40 foot in size.

And there are some giant versions of that hawk or that vulture that I showed that probably got up to 180 pounds and flew about 6 million years ago. These began edging towards people type weight. And the giant vulture was probably around 20 foot wingspan, getting up towards span that involves real airplanes.

So there got to be, at the beginning of this century, some interest in human powered flight. A lot more interest at the very beginning because people didn't know about engines. But once engines began, the interest in human powered flight sort of evaporated. But an early prize was to see how far you could go just using the kinetic energy of your momentum as you got a bicycle and significant prize.

Competitions like this do help the field move along. There's another prize put up in the middle of the '30s. This is one of the planes that attempted to do it. And they're really very great pioneering airplanes. Person in there pedaling. Couldn't qu9ite climb, but could greatly extend the glide.

But I think it then sandbagged with the requirement of the government, I believe in Italy, that this had to meet all the strength requirements of regular commercial aircraft even though it would never fly higher than 10 feet. And that rather limited it. It was a great pioneering effort. And then a big moment in this field, there had been a man powered aircraft group associated with the Royal Aeronautical Society for a while.

Henry Kremer was a friend of some of those people. And after selling a division of one of his companies, he had a party to celebrate and asked one of these people how is that human powered airplane stuff going. And his friend replied it wasn't going anyplace. They're just sitting around talking to each other. It was going to take something like a prize to make it go to get that field going.

And Kremer, who was starting on his third martini, said I'll put up a prize. And that was the deep insight that went into what I think is one of-- you'll find from the consequence-- one of the most creative activities in the 20th century and does get you to think about the importance of ethanol as an energy producer or liberator. Anyhow, Kremer is short fellow right there.

And right after his prize came out, teams in England began focusing their attention on really getting stuff out. Not sure which plane this is. It might be the Puffin. But they built several large span quite sophisticated, though sophisticated-- one of the definitions of the dictionary is unnecessarily complicated. You wonder why so many ribs and so on. Well, it's easy to be judgmental long after the fact. This was a great pioneering activity.

At the time, illustrated some of the difficulties but illustrates some of the successes. And they were able to actually get the plane like this off into the air under the high power that a pilot can put out for a very short period of time. But it couldn't turn. And when it crashed, it would be six months or so before they'd be back flying again because of its complexity.

Ignore the Albatross that followed later. But there began being various planes that no need to go into. If you really want to get the history, there are bunch of books that give it in delightful fashion. But a bunch of groups did work on this.

But the surprising thing was after the first flush of success the first few years, it turned out people weren't getting any closer to winning that prize, which was ingeniously-- the rules were ingeniously put as a figure eight flight around two pylons half a mile apart.

Required something to be able to turn left, turn right, go up high enough the beginning and the end of the flight. So it couldn't be just some exaggerated ground effect. Machine. It took long enough so you couldn't get by on that anaerobic power, where a pilot can put out one and 1/2 horsepower for a few seconds. It had to be the aerobic continuous power where he's down to more like a third or half a horsepower.

I had no interest in the subject at all, but I had a background that was fairly useful to prepare me for this-- incidentally about the only interest I was-- like everybody in the [INAUDIBLE] activity-- I was aware of the competition. And I think in the 1974 MIT event I was back here and actually saw movies of one of those planes fly-- I think might have been Jupiter-- and it was very dramatic and that imprinted itself on my mind. But I had no interest in the whole topic.

But I did have a background in model airplane building when I was a youngster and I'd make these indoor models-- somebody else's, I'm not a youngster here. But thing like this would weigh about a gram for the model for a one meter wingspan, and the rubber band that powers another gram, and they've gotten up to one hour flight indoors with these. The propeller just slowly goes like that and it moves through the air like a fish gliding through an aquarium. It's a art form-- turns out to be amazingly analogous structurally and stability and control-wise to Gossamer airplane.

Is also familiar with hang gliders because with my sons we were playing with these as the sport is getting pioneered in Southern California in the first half of the 1975-- 1970s and, again, came to appreciate the virtues of tubes in compression, exterior wire bracing, simple sail construction. Well-- and I was also involved in streamlined bike activities. The International Human-powered Vehicle Association began getting going, then go as fast as you can with no rules. Rules stifled bike development for a long time now. Just go as fast as you can and great developments took place. And through that I was getting very familiar with exercise physiology, championship bicyclists, exercise training techniques, and so on.

And then on vacation trip my mind-- got away with my mind daydreaming. It's very hard to find any daydreaming time these days with so many pressures. But the only time I've ever gotten a big idea is when I been daydreaming-- mind thinks for itself, decides on what it wants to think about, and it was connecting some things in my mind-- one of which was-- gotten a debt because, as a good guy, guaranteed somebody's note at a bank for a $100,000 loan to start a company which didn't succeed. He couldn't pay it back. I was stuck with a note and didn't have the cash to do anything about it. But I assure you that was stuck in my mind some place even on vacation trips. Your unconscious would nibble away at that.

I was aware that-- had no interest in the Kremer prize which I had-- I did know was up to 50,000 pounds. But, once, in middle vacation going-- I looked the newspaper, I found the pound was worth $2 at that time, and suddenly this light bulb just glowed over my head. Why that's the same amount as my debt, how exciting and important human-powered flight is. So I began concentrating on it very hard and tried-- I'm an aerodynamicist, I should be able to figure things out. But every design I came up with were like those people in England that were not able to-- that didn't come close to succeeding with big teams, and big, complex, elegant airplanes, and I batted my head against that wall for a while-- gave up, went off did other things.

I was doing some studies of bird flight-- timing how long it takes for a bird to go around in a circle, look at the bank angle, you can tell it's flight speed, flight radius. And then I began comparing this bird with that bird, comparing-- doing the scaling laws that relate different size, and weights, and speed, compared that with a hang glider and the sail plane, and this hobby thing suddenly-- as often happens-- I thought back about human-powered flight and realized, hey, it's all solved. There was an easy way to do it which is if you make something large enough and light enough-- if the weight just doesn't go up and you can keep making a thing like a hang glider bigger, and bigger, and bigger-- no matter how ugly it is-- if it's big enough, you can fly it on very low power and so immediately made a model.

As soon as that vacation trip was done, you see here that tested how you make a very large wing. I had no knowledge of wing structure, but I had knowledge of indoor models and so on-- just used logic. This is the best way to make a lightweight structure. And that's the model. And about two months later we were flying the first version of the Gossamer Condor-- 55-pound weight with my 105-pound son flying at the time, who would fly as slowly as six miles an hour and had a lot of problems with it-- in everything. It exaggerated the problems so that you can identify and understand them.

But it had one great feature which is it was quick to repair, modify, alter, redesign. And if it crashed on landing-- you didn't grab it properly as it slid a little sideways-- because stability control was just awful-- and a tube broke, you'd get a broom handle and some duct tape and tape the broom handle back on. You'd be flying in five minutes. That accident would have kept those people in England not flying for something like six months. So we got huge amount of flight experience out of this. Learned all the difficulties. It's just so thin, fragile. It seems as though the shadow looks a little more solid than the airplane does.

Well, we began sensing the reason for some of these problems was an apparent mass effect that exists on all airplanes but completely negligible. The mass of air to which you're coupled on the plane and regular plane is negligible compared to the airplane here. It was much, much larger than the mass of the airplane and the person. And it was affecting what was going on, affecting the controllability, and the total energy during acceleration, during turning, why we couldn't turn.

We used advanced computer models on stability and control, trying to get answers about this. And all the computer models said is those flight observations you made-- which is there was nothing you could do to that wing in drag [INAUDIBLE], drag rotors-- that would make any difference, just keep flying straight and maybe sliding off on a side. And that's what we saw and that's what the computer said, yeah, that's right.

It didn't tell us what to do, so I put a couple of sticks together that had Gossamer Condor proportions, shoved it around in the swimming pool-- as you see here. Here's one of the sons doing it, with your hand just feeling like a force balance in a wind tunnel. But here, you're working the fluid almost a thousand times denser than air so that apparent mass effect is really emphasized.

And within five minutes, we had the main answers, what the inarticulate computers hadn't been able to tell us, and we came up with the final design. A lot of the designing in detail was done by friendly friends who I'd lured into the project. It was very much a team effort. They were experienced. They had built airplanes, boats, so on.

And this is the way the drawings were done. We never had a set of plans until after the prize was won. The prize was not for drawing plans. It was for doing the flight, and we didn't have to worry about numbering plans and storing them and so on. Yeah, we used computers on prop design and some airfoil and stuff like that when it was needed. When this was okay, that's what we did. And wind took care of erasing stuff when you were done. It was appropriate technology. It's not the way to design airliners, but that's what we did.

And a little bit on the construction-- aluminum tube. If the wall was too thick, you'd chemically mill down to the correct thickness. And looking in the wing, just a lot of pieces of tape-covered Mylar. Now we're making a double surface plane. And got my youngest son-- or middle son, Tyler. Another person had been doing the main test flying, but that person had to go off to Belgium.

So Tyler did a bunch of the test flying. Next, just working out on a [INAUDIBLE] to build himself up. The amount of power you have to put out is about proportional to your weight. And a young person-- older person can do it. And he had some flight skills and he works cheap, so we got him. And with a new version, it was flying beautifully right off the bat, but still a lot of little problems with it and structural and we needed to lighten its weight and so on.

But it was kind of going in the right way. We then decided we-- it was going okay and now we needed a real pilot, Bryan Allen. And here he is with some of his exercise training. We were very lucky to locate him. He's a gifted pilot, but also very good on stamina-- willing to fit into such a project, works on airplanes, and we were just so lucky. But the biggest-- the most important thing in this project was lots of luck, and getting him was a big part of that.

Now let's have the next video-- rather than showing you a lot of Gossamer Condor things, this video, taken from the kiosk at the National [AUDIO OUT] will show some of the flying.

[VIDEO PLAYBACK]

- [INAUDIBLE] led by Dr. Paul MacCready of AeroVironment Incorporated. The development of the Gossamer Condor took a year and was a friends and family affair. The earliest version demonstrated the validity of the team's design approach-- a huge, feather-weight, slow flying aircraft.

- [INAUDIBLE], the air's speed is okay. Sock it to it.

- It's twisted a bit. Let's get up about 3 feet. Okay. [INAUDIBLE] 35.

- Let's go, [INAUDIBLE]!

- Stop pedalling! Stop pedalling. Pull a left!

- You go get him.

- Oh! The [INAUDIBLE]--

- Oh, yeah. Hold this up.

- Hold it up there. You look--

- Hold it up there--

- Get up--

[MUSIC PLAYING]

- The builders learned from both crashes and computer programs, and they made many changes to create the final airplane with a 96 foot wingspan and weighing only 70 pounds.

- Where are the nails?

- Six minutes and two turns later, the only obstacle left is the 10-foot finish pole.

[SHOUTING]

On his prize-winning flight, Bryan Allen landed with the words "we did it," a tribute to the teamwork that made the Gossamer Condor fly into aviation history.

[END PLAYBACK]

MACCREADY: This is a shot during that flight. The flight was great. The pressure was off. The prize was won. A good bit of it had been consumed. And expenses on the project-- and there was always a team. I'm sorry that the only way you'll get the idea of the teams on all of these projects is to read the publications. They were not a one-person effort at all. The team is very important.

Here's Kremer at the prize event in England. Wonderful for us. Prince Charles gave the actual trophy and check from the Royal Aeronautical Society. And setting it up in the National Air and Space Museum, where we have recently, last year, cleaned it all up. And we didn't think was going to last there more than two years, because it was also baggy and floppy and tape pulling out.

But now it's kind of cleaned up and we put a mannequin in that looks just like Bryan Allen so people can see which way it goes. And the kiosk video shows a lot of people flying it after the prize flight-- old ladies and little kids and so on-- to make people realize this was kind of a person-next-door project, not some big aerospace firm activity.

Kremer came out with a new prize, taking 18 years for somebody to go a mile. He thought it'd take another 18 years for somebody to go 23 miles across the English Channel. But we realized if we just cloned the Gossamer Condor, cut down the power required-- 20% or so-- and selected the right day, the pilot could fly much, much longer and do the job.

But now we use carbon-- now, no new ideas in the aerodynamics. It wasn't all that interesting a project. But in the structure, carbon tubing instead of the aluminum and many more ribs, much more accurately contoured airfoil and so on, and flew perfectly right off the bat. But like our previous ones, there were various-- there were some crashes.

And as we assess the situation, it looked as though to get enough testing on this, to get it over to England and back was going to cost a bunch of money. We were able to get the DuPont company to spring for sponsoring the project and letting us keep the prize money as a carrot out in front of us. And so the project charged ahead. Here doing some quick flights as we began building-- cleaning up the first plane.

We'd put my youngest son-- because he only weighed 80 pounds-- in it, and you could just push it around and nothing would get hurt if it hit hard. And then fix it up and Bryan Allen was doing a good job flying, but he was only able to fly about 20 minutes with this particular prop. And by going to a different prop that Jean Larrabee had designed and people at MIT here helped us with or actually did the detail design. Then we did the building.

This optimized the prop very elegantly for the crew's condition on the flight. And plane-- Bryan did a flight of about an hour and 20 minutes, landed and felt he could've gone on forever. So we were off to England miraculously. We didn't know how to get to England. But in the middle of the night, I get a phone call-- very muffled of all those airplanes at Nellis Air Force Base at 2:00 AM on Saturday. And that was the message.

And so there was a C-130 from the Royal Aeronautical Society. Three human-powered airplanes were all crammed inside it, and all our belongings, and so on. It was just another-- good luck is more important than anything.

Bryan Allen doing a lot of training in England, and training with Joe Mastropaolo in hot, humid conditions with no air blowing on him in order to get training for what it would be like in the plane during the flight. Then on the day when the weather looked as though it just might be okay, we're on the Warren near Dover getting ready for the flight to begin. Let's have the next.

Wait a minute, before the video begins-- the take off, because of that prop, was great for cruise but it was rather poor for takeoff when you're going very slowly. And we hadn't realized how bad. We'd always done it on big airports before.

Here we put out a little runway, a piece of plywood. The wing running wasn't done quite right, and the plane got just off the plywood, and the little toy 2-ounce wheel fell into the only little hole in that big acre of concrete, and snapped. And so there is the plane. That was our start.

And this is an audience participation exercise. You're asked to see if you can figure out who is the DuPont representative who is running the project. But about 10 minutes later, the plane started on what was the most fantastic journey, most fantastic physical stamina event that I've ever heard of.

[VIDEO PLAYBACK]

[MUSIC PLAYING]

- Doing okay, Bryan. You're looking good, Bryan. You're looking good. Heading in there, good buddy. It's downhill from here.

- Numbly, Bryan pedals on, no longer counting time. His flight instruments no longer function and his water supply is exhausted. When at last he sights the French coast through the haze, his heart sinks. It is still three miles away.

- Go, Bryan.

- For Bryan, each moment now has become a victory. Dehydrated, suffering severe leg cramps, his judgment has begun to waver. Briefly, he considers crashing on the rocky point.

Instead, he fights to save the Albatross from the turbulence that [INAUDIBLE] added and nearly wrecks it a few feet offshore.

- Come on, Bryan.

- Then slowly, at last, he's done.

[CHEERING]

[END PLAYBACK]

MACCREADY: And a bigger team, but many of the same members from the first team on this project. We never had so much pressure, and I've never been so exhausted. And all the people, we were using psychokinetics or telekinesis or whatever for lifting Bryan during that whole thing, from the boat. It was tough.

This shows at Aerovironment, we're into a lot of different things. And when these human-powered airplanes began, it spawned a big list of projects that are ongoing now. And we're growing, I think 240 people. We're growing as fast as we can find really qualified people. And it relates to ground things and energy things, with a lot of commonality between all these.

There are many too many things to describe that the Gossamer aircraft led to. The important point is that it led to just so many things that I heartily recommend everybody should get $100,000 debt to get themselves moving. And also get some projects that don't require a product the next year, but let you really explore the frontiers of some technology.

Here's the first solar flight. They're 80-pound sun, still, because we didn't have many solar cells and that actually climbed a little bit just on the power of solar cells. This is Bionic Bat, that won two of the Kremer Speed Prizes. And here's a flying telephone pole that's very hard to describe. But it's amazing what things will fly out at El Mirage.

And well, I'll go back on this. As a human power-- this is the last of the human power slides. This is a human-powered airplane that our son's figured out how to do. And this kid can walk a whole city block with his hands in his pockets.

And just the up-current of the air going around his body and over his forehead will keep that airplane up there. We have not found this to be a marketable talent, unfortunately, and he's just home goofing off right now. Let's have the next videos. Made some big planes--

[VIDEO PLAYBACK]

But also some little planes. Here you see a little thing weighs 1.8 grams zooming around the room, and under radio control. It's got a video camera in it, and all the telemetry, and so on.

Buddy will catch it on this one, which is the preferred landing technique. And then on the next go-around-- we've flown these inside auditoriums like this, and now you'll see what the airplanes saw. It was very crude camera. We have better ones now, color, and higher light level, and so on. But you are there. Okay, next video, please.

[END PLAYBACK]

The next video, I won't have time today to show you the Birdman contest. I'm showing you things that we did. Birdman contest in Japan, they have 70 human-power or glider aircraft fly that are just wonderful. It's a wonderful training aid.

It seems silly. They're all destroyed. They go out from a 10-meter platform over the water, and they all land in the water, and that's the end of them.

[VIDEO PLAYBACK]

[MUSIC PLAYING]

But I can show you this-- "Doing More with Much Less" that you can get a free copy of.

- Doing more with less is a vital feature of a world that works, where our increasing demands are met, yet do not overwhelm the limits of the Earth. Some of the unusually efficient vehicles with which Aerovironment has been involved serve as visual metaphors for the theme. Most dramatic is the unmanned, 100-foot, solar-powered Pathfinder, here undergoing low-altitude tests in late 1993. Versions are aimed at eternal flight, or at least flights for months above 65,000 feet, to carry equipment for surveillance, stratospheric monitoring, and telecommunications.

MACCREADY: Last summer, it went 75,000 feet, higher than any--

- The fragile, 70-pound Gossamer Albatross was pedaled 23 miles across the English Channel in 1979 to win the largest prize in aviation history. It demonstrates what can be done with low power when new concepts of efficiency are unleashed by challenges not burdened by constraints from narrow rules or the need for commercial production. It is a catalyst for new perspectives that can lead to useful insights and products such as the Pathfinder. And incidentally, it was a tribute to the human spirit.

The more primitive and fragile Gossamer Condor was the first really successful human-powered airplane. The final version can be seen at the National Air and Space Museum, where it was installed after this 1977 flight won the first Kremer Prize. About this time, the International Human-powered Vehicle Association was starting to organize competitions for land vehicles, without the inhibiting effect of rules-- just go as fast as you can. The streamlined Gold Rush finally exceeded 65 miles per hour, and a two-person version averaged over 50 miles an hour on a 40-mile freeway trip.

Later competition started to include some less extreme practical vehicle categories, no match for our wonderful modern cars, but valuable in suggesting that some transportation need not involve large amounts of steel and oil, and can be healthy and fun. Pioneering for speed from human power has resulted in some amazing water vehicles. This Flying Fish hydrofoil lowers drag by flying on a submerged wing. It has been pedaled at 18 miles per hour, and can beat the best eight-oared racing shells.

In 1987, General Motors teamed with Aerovironment for the rapid development of the GM Sun Racer to be entered in the World Solar Challenge to cross Australia on energy from sunlight. It won, speeding 50% faster than the runner-up, and averaging 42 miles per hour on only a kilowatt of power. Batteries to store the intermittent energy from the sun for vehicle use are essential, and obviously, for non-race purposes, they can be charged from the utility grid without need for solar cells. This solar car race helped emphasize that battery-powered cars can make sense.

Next, the same team combined to create the battery-powered Impact demonstrator. To show that cars emitting no pollution can be part of our transportation future, it needed adequate range and snappy acceleration. Here, it zooms from 0 to 60 miles per hour in eight seconds.

Now many groups are increasing priorities on battery-powered vehicles, vehicle efficiency in general, and broader transportation issues. Impractical human-powered airplanes, streamlined bikes, and solar-powered cars now seem more valuable as some of the ideas they ignited evolve into socially desirable vehicles aimed at a mass market. Globally, bikes are widely employed for personal mobility, transport of goods, and recreation. For some uses, battery assist, a scaled-down version of electric car technology, makes sense.

You can get the help of a virtual peddler, here hidden in the saddlebags, who weighs only a few pounds and never talks back, not to turn your bicycle into a motorcycle, but to let you do for 30 minutes what your normal ability would let you do for only three minutes. You can extend your commuting range with his bionic hybrid that will never run out of gas. You can match performance between individuals or not be bothered by hills on a hot afternoon.

A tiny airplane, the AV Pointer, serves for surveillance, in effect a pair of roving eyeglasses, a cutting edge example of where miniaturization can lead if the operator is remote from the vehicle. It is convenient to carry, assemble, and launch by hand. Battery powered, it is silent and rarely noticed.

It sends high-resolution video pictures back to the operator. With onboard GPS, it can navigate autonomously. And it is rugged enough to self-land without damage.

The modern sailplane is superbly efficient. Some can glide as flat as 60 feet forward for every foot of descent. They are powered only by the energy they can extract from the atmosphere, an atmosphere Nature stirs up by solar energy. Humans and soaring birds have found Nature can be generous in providing replenishable energy. Sailplanes have flown over 1,000 miles, and the altitude record is over 50,000 feet.

The Solar Challenger was made to serve as a symbol that photovoltaic cells can produce real power and will be part of the world's energy future. In 1981, it flew 163 miles from Paris to England, solely on the power of sunbeams, and established a basis for the Pathfinder. The message from all these vehicles is that ideas and technology can be harnessed to produce remarkable gains in doing more with less, gains that can help us attain a desirable balance between technology and Nature.

The stakes are high as we speed toward a challenging future. Buckminster Fuller said it clearly. "There are no passengers on Spaceship Earth, only crew." We, the crew, can and must do more with less, much less.

[END PLAYBACK]

MACCREADY: Thank you very much.

[APPLAUSE]

John Langford takes over.

LANGFORD: Thank you very much, Paul. And I'd like to say thank you very much, too, to Ed Crawley for organizing this. This is a great opportunity and a great event to put two programs together here.

What I'd like to do, if we could bring the first slide up, bring the lights down and the first slide up, is to take up where Paul left off, in many ways, in the story of human-powered flight, and talk for a few minutes about the MIT side of it. And in particular, it's the Daedalus Project, obviously, that has epitomized this. But I'd like to speak as well about the whole history of this, with an emphasis on the role of these things as student teaching tools, because they have played a unique role in the department over the last 20 years or so.

This is the famous image of Daedalus 88 arriving at Santorini 10 years ago just last week, after about a four-hour flight over 72 miles, 115 kilometers, the product of a three-year program here at MIT and piloted by Kanellos Kanellopoulos. And it's a very great pleasure to have Kanellos here today. If you could stand up for a minute, Kanellos. This is his first time in the United--

[APPLAUSE]

This is the first time that Kanellos has returned to MIT since he was here before the flight training. And we're delighted to have him and so many other members of the Daedalus team back. So I mentioned the project really goes back 20 years or so.

And many of the themes that Paul was talking about a few minutes ago play right in in here. The Kremer prize served as the impetus for and the stimulus for a number of student projects beginning here in the early 1970s. This aircraft was one of two called the Biplane Ultralight Research Device, or BURD, which were built here in the Department by the two teams or several teams of students during the early 1970s.

This was what the finished configuration looked like. This was about a 60-foot span, two-person aircraft. And as Paul has just narrated the story of the Gossamer Condor, once the Condor won the Kremer Prize, the first one in 1977 for the figure-of-eight flight, interest in these projects languished somewhat.

As Paul mentioned, there was a subsequent prize offered for cross-channel flight. There had been a number of other activities here at MIT. The one that our group particularly came out of was the model aircraft group and the Model Rocket Society, which had been actually pioneering the techniques that Paul showed a few minutes ago in that micro air vehicle flying around inside, which is now a program supported by DARPA, the Defense Projects Agency.

And one of the big advances here at MIT in the late 1970s was the miniaturization of radio control technology and its application to these small, radio-controlled boost gliders, here flying for the US team in the World Championships in 1978, where Harold Guppy Youngren won the first World Championship in this event. We got involved in the activity of human-powered aircraft. Here you can see there's Guppy, the world champion on the right, and Professor Drela in the center, driven by the interest in this as student projects supposed to be fun and interesting.

As Paul alluded to, though, there were some very serious aspects of this, as well. And one of the first areas that the MIT group really was able to distinguish itself in was the design and the application of numerical methods to airfoils, and particularly to propellers. And as Paul mentioned, Gene Larrabee was influential in this, bringing the methods of Pranel and Betz and Gloward and updating them from for computer execution.

And it was really a generation of students there working under Gene that coded that up. And the propeller became the first real visible implementation of this. This is Mark hot-wiring a piece of that propeller, these large, four-meter diameter props built in little six-inch-long sections here.

And then, obviously, there was interchange back and forth all throughout this with the two teams. We were able to design the propeller for the Gossamer Albatross aircraft. And Paul contributed enormously to the efforts here at MIT, providing a lot of tips about how these aircraft went together, particularly the lessons from the Condor and the Albatross experience, and as well as providing material.

All of the skin covering, the Mylar for the first Chrysalis aircraft that we built were donated by Paul as part of this. This is the spring of 1979. Guppy and Paul here, and I think this is in Henry Jex's backyard. Henry is here today from Santa Monica.

This was the aircraft that resulted from our efforts, Chrysalis, a large biplane, 72-foot wingspan, not really intended at the time to be a serious contender for the cross-channel prize, but as a way of getting a new generation of MIT students into the air. It was distinguished, I think, by a number of firsts. Certainly at this point, it had among the highest number of flights ever made, something like 350 flights on this airframe without a crash or serious rebuild on it, and holds at least one record that continues to stand, which is to our knowledge, the only person who has ever flown both under their own power and has flown in space is Jay Apt, another MIT graduate who flew the Chrysalis among many others in the summer of 1979 there.

The Chrysalis project was overcome, of course, by the Albatross, which won the Kremer Cross-channel Prize in June of '79, a few days after Chrysalis made its first flight, which I think Paul has narrated fabulously for us there. And there was a subsequent series of Kremer competitions called the Speed Prizes to make airplanes smaller and hopefully, more practical. We were able to win first place in that competition with an aircraft here called The Monarch, which was built and flown in 1983 and 1984 out at Hanscom Field there.

The idea here was to fly a sort of a metric mile flight, 1,500 meters. And the first one in under three minutes, I think, won the 30,000 pound prize for that flight. That was a great experience.

But the combination of the Chrysalis experience, the Monarch experience and the Gossamer series left a number of us wondering where this would lead if it wasn't driven by the impetus of the prizes. The prizes certainly provided a good focus point, but they also put an emphasis on how fast and how quick and dirty could you do this. And there was an element to this of, if you didn't have that as a stimulus, and you were just trying to push it to the max, how far could one of these things go? How far had the technology really progressed?

Because you have to remember, it was moving very quickly in this period, with computational aerodynamics, composite structures coming in. How far could you push this? And that led us into the thinking of was it possible to take this all the way back to the oldest Western reference of man flying under his own initiative-- that is, the story of Daedalus and Icarus, which was the team, according to legend, imprisoned on the island of Crete back in the Late Bronze Age, who built wings of feathers and wax and flew to freedom.

Two aircraft built there, obviously, a story most famous because of the two, the son, Icarus, flew in the story too close to the Sun, which melted the wax holding the wings together. And he fell to his death. As is true even to today, the crashes get all of the attention. And history had pretty much neglected the idea that his father, Daedalus, had made it safely.

And that story became the driving force behind the idea of the Daedalus Project here at MIT in the middle 1980s. This is the flight route. When we first started on that project, we assumed rather naively that it would be possible, as good engineers, to go look all this up, and find the exact flight route, and literally recreate the route that Daedalus had flown.

Obviously, as we began to get into that, we learned a lot about a lot of things during this project, classical mythology being one of the first, and of course, that there is no literal recreation possible-- that myth-making is a creative process and builds up over time. But applying the navigational strategies of the day as mariners practiced them to the idea of flight, it was pretty clear that anybody who was trying to fly from Crete and Knossos-- the ruins were actually discovered in the early part of the century here on the north part of Crete-- the nearest major landmass is up here, the island of Santorini, which is 72 miles or 115 kilometers, about three times the distance of the cross-channel flight, north of the island.

And whatever your eventual destination was-- and the myths do disagree on the eventual destination-- the first step would have been to get off to the island and to get to Santorini. And so that became the flight route that we undertook. So we began looking into this.

It was a research program not only in aeronautics, as I mentioned, but in many other areas. The meteorology was an important one, as we began to look into the weather in the region. Obviously, Paul talked a little about the difficulties that Bryan faced both in terms of the physiology and the meteorology. We began to address those right off the bat.

The existing weather database didn't have the resolution down in the low-wind conditions that we needed. So one of the first steps was to deploy a series of small, automated weather stations there for a year or so before the flight, as we looked for an envelope of weather conditions-- calm wind for four to six hours and low temperatures.

Temperatures were very important because of the engine. An engine research program was undertaken down at Yale University. This is Dr. Ethan Edl, who was the project's lead physiologist in a program that first attempted to sort of quantify what human performance really was, so that we could use it as engineers, and put it into the aircraft sizing, and optimization models.

In addition to the physiology, probably the single most important technical advance was numerical aerodynamics, computational aerodynamics and as practiced by Mark Drela. I think those of you who attended the symposium here, it's really striking. One of the real things that came out of this program-- Mark's codes.

Now, of course that may have been a criterion for getting invited to this symposium. But I think that every single speaker there, on whichever coast or continent, is using a version of the ISES or MCs or XROTOR codes that Mark developed, and that were first implemented here in the Daedalus project, which provided the aerodynamic designs on all of the flight surfaces-- propeller, wing, tails, everything.

Another big part of this was the structures. To get the kind of performance we were needing, we really had to maintain large area of laminar flow. That was partly computationally done through Mark's codes, but then we had to implement that.

The structures had to be built that were capable of sustaining that laminar flow. And numerically controlled foam cutter was designed and built, and used to precisely cut out all of the different airfoil shapes that went into covering the leading edge. You can kind of look at the Daedalus, and see that the pink areas are the areas of laminar flow.

Obviously, the foam isn't very strong, and you have to have a backbone to that, which was the job of Juan Cruz, who is now down at NASA Langley as their composites expert. But this was an all-composite aircraft with one wire bracing. And this is a picture of the full wing being proof-loaded in a test out at the Lincoln Labs hangar.

I wanted to recognize the critical role played by Jack Kerrebrock in all of these projects, because Jack has been the project's advisor and sponsor in this. Every time we started one of these projects, once we got past the initial brainstorming, the first thing we had to do was go into Jack and ask for some money. And whether it was in his office here as Department Chair for Chrysalis or when he was at Monarch, we had to go down to-- he was a NASA Associate Administrator-- we had to go down to NASA.

And when he was back for Daedalus, he had moved up to the Dean's office. And Jack has been a critical supporter of this throughout the whole history. And none of this would have happened, I think, without his support.

We got the support from unusual places. One of the ones was-- the main sponsor for the prototype of the Daedalus was Anheuser-Busch. And the aircraft was named by them, the Michelob Light Eagle. And obviously, their target market was the college crowd. Here's Tom Clancy modeling for an Anheuser-Busch ad, I think, in this one.

And that's the aircraft flying in January of 1987 out over Rogers Dry Lake in California. It was flown for a series of five record flights by Lois McCallin and Glenn Tremml, including records over straight line and closed course records. It broke the Albatross's record with a 37-mile flight.

And then the Light Eagle went in and served as a test bed. It was heavily instrumented. You can see the different instrumentation that was put on it.

It became a real flight research aircraft, collecting the quantitative data that was needed both for the Daedalus airplane itself, for subsequent human-powered airplanes, and also for some of the high-altitude things that Paul alluded to, the very lightweight, very flexible structures that you need in solar-powered aircraft, for example. This was a test bed.

NASA sponsored part of their research program. And there was a lot of instrumentation that went on the airplane. Of course, all of you associated with the project know that the title of this picture is-- "I don't understand. It worked back in Cambridge."

By the time the Light Eagle had completed its program, we moved into the Daedalus phase itself. And we began the construction of two very refined versions of the Light Eagle, which were the actual Daedalus planes. And at this point, we began to transition to yet another generation of students.

The UROP program, the Undergraduate Research Opportunities Program, played a big role in this. This is Guppy here, who served as the Chief Engineer on the Daedalus planes, instructing Tom Clancy in some fine point of how these aircraft are built. This is Juan with two other UROPs here in a composite test program, as we began every piece of the structure in the Daedalus planes underwent proof load testing. And then the numbers were fed back into the final designs.

And most of the construction was done by the UROPs. This was, at times, a controversial strategy. There were some members of the department who grumbled that the project was using the UROP program for slave labor. And it was never clear to me where they got that impression, but anyway.

And we did work hard to employ everybody in the program. The pilots, even when they couldn't help build, we put them to work. Here, they are selling patches onto the team jackets the night before the rollout.

This was the Daedalus plane, as finished in late 1987. The rollout was in October. I always remember that, because it was the day of the great 1987 stock market crash, and much to the dismay of the people from United Technologies, because there was no mention of the Daedalus rollout because of the large crash.

There were other crashes later in the program. This was one that occurred in January, I guess actually early February of 1988. This was about 21 days prior to the shipment to Greece.

We had a Greek C-130 scheduled to come and pick the airplane up. And we had four minutes of flight time. And then we had the airplane crash. We lost the plane, the first plane in-- that was February of 1988.

Fortunately, we had been working on a backup. And we brought the wreckage of the first plane back, rushed the completion of the second airplane forward. And by early March of '88, we had the second plane flying.

And the cause of the accident was essentially typical, not uncommon in engineering projects. It's a failure to communicate among two parts of the engineering team and the design team. And the fundamental problem was that the aircraft, which had depended on its dihedral for roll-yaw coupling, for lateral control, the bracing wire which really controls that dihedral angle was cut too short. And that wasn't caught in the manufacturing or checkout process.

And the aircraft didn't have adequate control. Once we had traced that problem and analyzed it, it was very easy to fix. And the second aircraft flew beautifully, made an abbreviated series of test flights, and then was packed up in a C-130 and sent over to Greece.

Once in Greece, there was a lot going on there. Obviously, the Aegean is a region noted for its changeable weather. And the aircraft had to be protected, so the UROPs went to work again, and we built a hangar.

We had purchased a prefabricated hangar and taken it over. That team went over a few days ahead of time. We had secured a small fleet of inflatable boats, which had been loaned to us by several organizations over there.

The engines had been provided here in the United States. And so we converted the UROP team from builders into boat teams. The first couple of drills here were pretty wild, with people overboard, and radios that went in the water, and all of that that went into making the flight.

But we had plenty of time to sort this out, because as the meteorology got worked through-- and this is Steve Bussolari here, the Director of Flight Operations on the program-- we didn't get very many opportunities. We knew that we wouldn't have very many. That we had five or six a year was the prediction.

And we were up against a weather cut-off, because it would get too hot in the summer. We simply didn't have the capability to keep flying into the summer because of the high temperatures that we would encounter in the region. We did have several false alarms, where we got up and went through the whole flight deployment drill, had the pilot sealed up in the cockpit there, sitting on the runway ready to go.

This is Mark, and I think that's Frank Scioscia in the cockpit on this, ready to go. And then at the very last minute, making the call that the conditions were not what we wanted all along the route, and scrubbing the flight, and putting the whole thing back in. There was a lot of waiting. The plane was ready and there was a lot of waiting, which was a very anxious period. It's a beautiful area there, but it was hard to relax and enjoy it waiting for this.

There was a lot of other dynamics going on. I love this picture, because it kind of captures all of the players we were dealing with in here. The military got involved because, of course, we were operating off a Greek military base. That's pretty obvious.

The Church was a little less obvious. The Church was involved because the issue came up of what if the weather was perfect on Easter Sunday? And there was great debate within the team about how to handle that.

We finally went to the archbishop, and briefed him on the project, and asked what his guidance was. He said, go for it. He said, if the weather's good, you guys go for it.

Gasoline turned out to be another factor that you wouldn't have thought would be a limit in a human-powered aircraft. Obviously, the airplane didn't need it. But all the boats did. And this was the supplies that we needed for one day of flying, or the boat support for a day of flight operations there.

The people who kept the busiest, I think, were the pilots. We had a team of five of them on rotation. This was because we had figured that this was going to be right at the limit of what human physiology was capable of, and we had recruited and trained five world-class athletes who were in a rotation, much like baseball pitchers, where they were on for two days and then in a rotation cycle off for four, six, or eight days, depending on how many were healthy. Obviously, injuries were another big part of this.

So the training regime was very important. They were riding hundreds of miles each day to train. They obviously came into the project as excellent athletes. They were all Olympic-level cyclists when they joined the project.

And in the course of the project, they were all trained to be highly skilled pilots. A lot of that was in high-performance sailplanes. They started in, obviously, lower training sailplanes, and quickly moved into high-performance sailplanes.

A lot of the training took place on a simulator, which combined a visual out the window display with an ergometer. Your power was actually being measured here as you pedaled. And that power reading was fed into the simulation and displayed. So you had the full flight controls, as well as the power going into the simulation.

And then once all of that was completed, you would fly the Light Eagle. The Light Eagle had become the training airplane. And once you had gone through this regime, you flew the Eagle. And one of the requirements was you had to get through a minimum of a two-hour long flight, a number of flights in the Eagle, including one at least two hours long, before you could get into the Daedalus. And once you had gone through all of that, you were checked out to fly the Daedalus.

This is one pilot's food ration for one day. And it's pretty amazing. The nutritionists from Shaklee Corporation who were a sponsor at this time helped go over, and sort of rewrote the whole diet of the kitchen in the place we were staying. And the pilots had this.

At first, all the rest of the team was pretty envious of this, because this looked pretty good. But then it turned out, as the day wore on and they realized that these guys had to eat the same thing every day, it became a little less attractive. The rest of the team got to vary their meal a little bit more.

The in-flight meal service was provided by Ethan Edl. This is "Ethan-ol", as we called it. It was a very high-performance drink which had been optimized to be right at the limits of what a human could tolerate in the system, in terms of replenishing the glycogen that you needed to keep your muscles functioning.

And Ethan had moved into this, and had developed this drink, had debugged it on the pilots through various versions. And there's actually a toned-down version, a consumer version, I think, that Shaklee is still marketing. There were, what was it, six quarts of that on the airplane or something like that, six liters, four liters.

After a period of what seemed like interminable waiting-- it was probably more like three weeks now in retrospect-- but we finally did get a day where things began to really line up across the whole Aegean. And the crew was brought out at, I guess 2:00 AM wake-up. And assembly of the aircraft began at about 4:00 in the morning. And the plane was put together there on the runway.

A lot of white knuckles in the boats, and watching as we got ready. And then Kanellos was given the go-ahead and took off. I mentioned that Kanellos was the pilot, by luck of the draw here that his number came up on the day that the weather conditions were good.

And so shortly after 7:00 AM, Kanellos took off from this runway, and went over the edge of this embankment here, and headed out. And the airplane which had looked so huge when you were up close to it suddenly looked completely different in terms of something that was tiny as he set out on this slide. You can see in the background there the big ferries that go every night to and from Athens.

And you can see the inflatables that are accompanying it, in case the aircraft had to ditch. We were prepared to take the airplane under tow. We had tried to absorb all of the lessons from the Albatross project.

And Albatross's strategy, for example, was to take a fishing line and try to hook a ring on the aircraft. Daedalus had a refined system that had a tow line in the airplane, so in the event that Kanellos wanted to be taken under two, he would have dropped the line, and the boat underneath taken it up, and towed it. Navigation was done from a command boat following behind the aircraft there.

This is a nice shot looking up. You can see the carbon structure there, and the region of laminar flow on the top. It really is laminar back to about 60%. Pretty much you can see where the foam goes to on the top surface.

The bottom is almost all laminar. It didn't need the foam. And here you get another view. This is looking straight down on the aircraft, and again, a good view of the laminar flow.

We had escorts provided by the Greek Navy and the Greek Coast Guard. Their primary role was in case we needed any emergency medical rescue. That was provided by the boats. And they also helped keep the route clear from other boats that would have gotten in the way.

This is a great picture, gives you a sense of the speed at which Kanellos was flying, and also the crosswinds that he was managing. You can see the crab in there. The boats, obviously, and the wakes are marking the direct flight route to Santorini there.

And this picture gives you a good sense of the smooth surface of the upper part of the wing. This is another good example of the "doing more with less" that Paul was just talking about, where the speedboat there has-- what is that, 120 horse motor on there, 130 horse motor on the back of that speedboat there. The Daedalus has a quarter horsepower motor in it, and they're going the same speed. And it's all due to the refinement of the technology and the application of technology to energy efficiency here.

The flight had been projected to take as long as six hours. We had trained for six hours, but the conditions were good, and Kanellos was just fantastic. His heart rate when he started was about 156, and declined throughout the flight.

By the time we were inside of Santorini, his heart rate was down to 126, which still just boggles my mind, how cool he was throughout all of this. Actually, by this time, most of the team had deployed to the landing site, and was watching, marking the site there with smoke. And then Kanellos had the choice of going straight in onto the beach.

A lot has been made of the fact that the aircraft broke up. I'm here to say, we were maneuvering this thing to try to get it back in one piece. Kanellos easily could have gone straight in onto the beach if the objective was just to get it onto the beach, but we really wanted to try to maneuver the airplane in and land it.

We had all seen that sight of Bryan Allen slipping it in there onto the beach in France. And that was pretty much the maneuver we were working on here. So Kanellos came in at fairly high speed, turns in parallel to the beach, and tries to slip it in parallel.

Here, you can see the beginning of the failure. You can actually see the buckling right there in the carbon tail boom, as a gust of wind, thermally induced coming off this black sand, catches this, torques the tail. Tail fails right there. The tail boom fails.

The wires or the cables that control the elevator are outside at that point. So as this torques, it puts a full-up command on the horizontal stab there. And that overstresses the wing.

You can see it fails out right near a transport joint on the right-hand side. And the aircraft drops into the water there just off the shore. We had a lot of people help us take it apart at this point. That was no problem.

If you go to Santorini, I'm sure there's still pink foam souvenirs in some of the shops there. And there's Kanellos after the flight, who no kidding, could have gone on for quite a while on this flight. And that's the team there on the beach, many of whom are here today. Could I get everybody who was on the team to stand up at this point, everybody who worked on the project? Could you stand.

[APPLAUSE]

Many of the people I think haven't seen each other in 10 years after this. And so I really do thank Ed Crawley. For pulling this whole thing together. The Daedalus project was done for education. It was done for research.

It was a marvelous project. It could never answer the question of, so what, when people asked it in the lectures. But one of the interesting things about science when you really are doing research is that you never know where the next problem is going to come from.

And in Daedalus, for me, anyway, it came from a very unexpected source. In the mid '80s, there were two things that emerged that kind of shifted the paradigm from nuclear holocaust being the sort of big-picture issue that kind of hung over all of us. And those two issues were the emergence of AIDS, the breakout of that into the general population, and the depletion of stratospheric ozone, in terms of issues that when they first began to appear, no one was quite sure how bad this was going to be, and that clearly, had the potential to eliminate life as we knew it in a worst-case scenario.

The ozone hole, obviously, appeared over Antarctica in the early '80s. And the mid '80s, a lot of attention was directed towards figuring out exactly what it was. The primary tools for doing that were large stratospheric balloons and an aircraft called the ER-2, which NASA operates. It's a version of the military spy plane.

And these worked okay for figuring out the causes of the Antarctic ozone hole, and providing the conclusive links between chlorofluorocarbons and the catalytic cycles that destroyed the ozone. But it was also clear that the scientists, to answer the question of, is this going to spread to other places on the planet, is this going to happen in the northern hemisphere, is it going to happen over the middle latitudes, that you needed to go out and take measurements at higher altitudes and in more places around the planet.

And a couple of us from the Daedalus project linked up with a group down at Harvard in the Atmospheric Research project there, and began construction of a series of aircraft that would attempt to apply the aerodynamics and the structures, and some of the project management philosophies that came out of Daedalus, and apply them to a series of small, very customized, robotic aircraft that could be used for atmospheric science, high-altitude research, initially in the ozone area. And we built an aircraft called Perseus, about 60, 62 feet in wingspan, developed the controls technology for that, and made a series of flights.

This is really to give you a sense of scale of the Perseus. This particular aircraft has carried about a 220-pound payload to an altitude of about 50,000 feet. And both the solar plane and the Perseus aircraft are working together, are joint participants in a NASA program that's developing the technology for future operational aircraft.

And we've also applied that to a larger aircraft that's really designed specifically around the needs of the scientists, called Theseus. And that's the larger, twin-engine aircraft in the back. And we have built-- this is a 140-foot wingspan aircraft that carries between 750 and 1,500 pounds of instruments onboard, and eventually to altitudes of 85,000 feet or so for fairly long endurances. This is an airplane that's in development, and is a direct outgrowth of the Daedalus technologies.

I wanted to close here. And if I have the time here, which I think I do, Corey can you queue up this short video? As you put that in, I just want to close with a few thoughts here on this picture, which is the layered structure of the atmosphere here, which is really a neat picture showing the whole path here. And I think the lessons that Paul has been talking about, certainly the lessons that we have drawn from Daedalus, support very much the idea that the atmosphere is, although it looks very large, it looks like it's an infinite sink for many purposes, it really isn't.

If you look at this picture, above that line is space, a very hostile environment. Below that line is Earth and everything on it that we know and hold dear. And that atmosphere is a very thin line that separates those two from each other.

It's amazingly under-sampled. There's still a lot to be done. And to the future generations of students who are coming along, hopefully some of whom are in the room attending this lecture today, there is still a lot to be done. And these types of programs that Paul and I have talked about here are great ways to get into it. I'd like you, if you can cue up this video, this is a piece that Brian Sullivan edited together of the flight.

[VIDEO PLAYBACK]

[END PLAYBACK]

Okay, thank you very, very much.

[APPLAUSE]

MODERATOR: Well, I think we have a chance to entertain a few questions from the audience, and then we'll wrap up.

AUDIENCE: I'd like to hear the tale of the [INAUDIBLE].

MODERATOR: Why don't-- Kanellos, why don't you come down here and tell us that? And then we'll close on that.

KANELLOPOULOS: First, thank you for the opportunity you give me to talk. Sorry for my bad English. About the last moment, there when I was pedaling towards Santorini was a tailwind. So no problem, no big problems. And over there, as John said, because of the high speed we had, they decide to make me do a turn.

So we did the turn. But during the turn, we faced the wind. And the wind approaching the land was too hard. So the plane was going up and down, like you have seen there.

This plane was not designed to do all those things. So it resisted too much. And one moment, I felt-- no, it was not my feeling. It was real. The plane was flying, but staying in the same place, because that wind had the speed of the plane.

So it was very tough. And then, it took a bank, and it was not possible to make it return back. So it hit it once, hit it twice, and then broken the tail. So it was-- but it was closed. But I think this end, because it was not so easy and smooth like the other, make a very-- put fear to someone else who wants to do the same, that it's not so easy.

[APPLAUSE]

MODERATOR: Well, with that, I think we'll conclude this year's Gardner Lecture. Thank you very much for coming.

[APPLAUSE]