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NASA CONNECT Script: The “Wright” MathJohn
Herrington At some point, everyone dreams of flying—to physically elevate themselves above their environment. Flight was a dream of mine when I was a kid. And this is what I do today. Hi, I’m John Herrington, NASA crewmember of Shuttle mission STS113 and I’m also a member of the Chickasaw Nation in Okalahoma. Every culture and every civilization throughout recorded history has a mythology involving human flight. One of the best-known legends of human flight is the Greek story of Icarus, who tried to escape from an island prison by using wings made of wax and feathers. Icarus flew too close to the Sun, the wax melted, and he fell into the sea. Ancient Chinese records speak of human attempts to sail through the air by attaching themselves to kites. In today’s pop culture, flight is common among comic book super heroes. And numerous Native American cultures celebrate flight in their traditional dances. But it was only about a hundred years ago that the problems of powered flight were overcome—and human beings finally took to the sky. In this episode of NASA CONNECT, host Jennifer Pulley will take you on a journey to find out how mankind first learned to fly. You’ll discover some secrets to the Wright brothers’ success 100 years ago. In your classroom, you’ll build your own flying machines and evaluate their performance. You’ll also learn how NASA engineers are developing new morphing technologies for the next century of flight. And you will explore the web to follow in the footsteps of the Wrights with some cool interactive activities. All in this episode of NASA CONNECT! Jennifer PulleyHi, I’m Jennifer Pulley. Welcome to NASA CONNECT, the show that connects you to math, science, technology and NASA. I’m here at the Wright Brothers National Memorial on the Outer Banks of North Carolina. This is where Orville and Wilbur Wright flew the first airplane 100 years ago.
Kid I’ve read that there were many inventors besides the Wright brothers trying to invent the airplane. Jennifer PulleyIt’s true—Many famous inventors including… …Alexander Graham Bell, Thomas Edison, machine gun inventor Hiram Maxim, and Samuel Langley—the Secretary of the Smithsonian Institution had all attempted to build flying machines.
Kid
My teacher said that the Wright brothers didn’t have high school diplomas and didn’t have a lot of money to work with. Is that true? Jennifer PulleyThey were both good students in school and Wilbur completed all of the courses he needed to graduate from high school. He just never picked up his degree. Both Wilbur and Orville loved to read outside the classroom. And you’re right; they didn’t have a lot of money to work with. But they figured out ways to conduct their experiments without spending a lot of money. They were able to support all their experiments through their day jobs—their small bicycle shop. KidSo, how come it was the Wright brothers who invented the airplane? Jennifer PulleyThat’s a good question. Why was it that these two little-known bicycle mechanics from Dayton, Ohio succeeded where so many other famous and successful inventors had failed? Well, to help find the answer to that question, we spoke with Dr. Tom Crouch, Senior Curator of the Division of Aeronautics at the Nation Air and Space Museum. Dr. Crouch, what was the Wright brothers’ secret to success? Dr. Tom CrouchJennifer, they were really good and intuitive engineers. In order to invent the airplane they had to come up with a process of invention – a way to solve really difficult, technical problems. Today, we call it the “Engineering Method.” The first thing that the Wright brothers did correctly was to Define the Problem. The Wright brothers studied the experiments of other inventors and quickly realized that many of them were missing the true problem. The Wright Brothers saw that the true problem would be maintaining balance and control in their machine. Many other experimenters were convinced that an airplane could only be successful if it relied on some method of automatic stability. They thought it would be impossible for a pilot to react quickly enough to all the changes that might happen to an airplane during flight. They thought it would be like balancing on the head of a pin—which is impossible to do. The Wright brothers saw things differently. They were bicycle builders and bicycle riders and they drew
on that experience when they thought about controlling an airplane. Imagine that you are trying to describe
how you ride a bicycle to a Martian or to someone who has never seen one. You might talk about riding down a hill on a tiny seat perched atop two very narrow spinning tires. In addition to which, you have these pedals you are going to have to work, and a handlebar to steer with and you’re going to have to coordinate all that at the same time. Jennifer PulleyI could see how the person you were talking to would think they’d have to be the world’s greatest acrobat to ride something like that.
Dr. Tom Crouch
That’s right. But the Wright Brothers knew that you internalize the business of riding a bicycle and they also knew that the same thing would happen with an airplane. You would learn fly an airplane and do it automatically. Jennifer PulleySo the Wright brothers correctly Defined the Problem.
Dr. Tom CrouchYes. They knew that control was the problem, so the Wright brothers… … observed the movements of soaring birds to see if they could figure out how they controlled themselves in the air. They thought they detected subtle ways that soaring birds altered their wings to maintain balance, but the Wrights were stumped as to how they would duplicate the organic movements of a bird’s wings… …in a very mechanical flying machine. Jennifer Pulley Which brings us to the next step in the engineering method— Propose Solutions. Tom, What solutions did the Wright Brother propose? Dr. Tom CrouchThey really struggled with how they could control the geometry
of their wing to control the motion of the flying machine. Until one day, Wilbur was in the bicycle shop and a customer
came in and asked for a bicycle tube for his tire. And Wilbur took it out, in a box just like this one. He was fiddling with the box, standing
there talking and it suddenly occurred to him that the answer to his problem
was right there in his hand. Wilbur noticed that if he put the thumb and his forefinger of one hand on these two diagonal corners, and put the thumb and forefinger of his other hand on the opposite diagonal corners, that he could squeeze the box back and forth. He noticed that the box twisted. In his mind, Wilbur pictured the top and the bottom of the
box as the wings of a biplane. With
a simple system of cables, he could draw the corners together turning
one set of wing tips up in the wind and the other set of wing tips down.
He realized in this way he could control the shape of his wings
and would be able to roll his aircraft in the sky. Jennifer PulleyOkay, so now the Wright brothers have a proposed solution. Warp their biplane wings. Using the Engineering Method, their next step would be to Evaluate the solutions using tests and prototypes. In other words, the Wright Brothers needed to put their wing-warping theory to the test. Dr. Tom CrouchThat’s right Jennifer. They didn’t begin by building a powered flying machin. They had to start by building and testing prototypes. And they started with this small biplane kite. Watch how this prototype flies!. Notice when you pull on the opposite strings, the kite rolls to the left and right. The wing-twisting concept Wilbur proposed from the inner tube box actually worked in his prototype kite. Jennifer PulleySo from the success of their kite, the Wright brothers built the first powered airplane? Dr. Tom CrouchNo, first, they built a series of three gliders over three years and what they learned helped them to build the world’ first powered airplane. Jennifer PulleyHey, that’s leads us to the final step in the Engineering Method—Select and Refine the Best Solution. And in order to learn how the Wright Brothers refined and improved their flying machines, we’re here at the Wright Experience laboratory in Virginia. We’re talking with Ken Hyde, he’s the founder of The Wright Experience. Now Ken, tell me, how did the Wright Brothers improve upon their flying machine designs? Ken
Hyde
Well, with each new design and each new flight test, they did small refinements and small changes to their design. There may have been many problems at any given stage of the flying machine’s development, but the Wrights only changed one thing at a time. They were never confused about which change was causing which result.
Jennifer PulleyKen, that makes sense. I mean, that way they could select the changes that worked and continue to refine their design. Ken HydeThat’s right. And Jennifer this is the result of all of their hard work! This is a flying reproduction of the Wrights’ 1902 glider. Jennifer Pulley
Ken, this is quite different from their original kite, isn’t it? Ken HydeNot really. It uses the same principle of wing warping and wing twisting that they used in the original kite. But what was so important and so radically different about this glider from their early designs was that the 1902 glider was the first aircraft ever that solved the problem of controlling an airplane in all three axis - pitch… roll… and yaw. Okay, Jennifer. This
is the control for the elevator, which controls the pitch, which is the
up and down movement of the aircraft.
To control roll, I can shift the hip cradle back and forth. Watch how the wings twist. That would
change the roll position of the aircraft during flight. But also wired into the hip cradle is
the control for yaw. Watch
how the tail moves at the same time as the wings are warping. Jennifer PulleyKen, this is so cool but can you really fly this?
Ken HydeAbsolutely! We have a 1902 simulator that you can fly. Come on! I’ll show you! Jennifer PulleyAll right!
Ken HydeJennifer this is our 1902 glider simulator and it was developed
from the wind tunnel tests we did on this machine. Bill Hadden is our expert on this
and he is a good instructor and he’s going to check you out on this
and tell you about the machine.
Jennifer Pulley
Great. Nice to
meet you, Bill. Tell me about
the simulator.
Bill Hadden
This was based on the wind tunnel numbers generated by taking
our full scale glider and putting it in the Langley full scale tunnel
in Hampton, Virginia; operated by Old Dominion University. And the results of the wind tunnel
tests were incorporated in the flight simulator by Burrough Applied Research
- that’s their business, making flight simulators. So when you fly this simulator you’re actually flying
wind tunnel data results. So it’s a lot of fun.
Would you like to try?
Jennifer Pulley
I thought you’d never ask. I’d love to try it, thank you.
Bill HaddenOkay Jennifer, on the left, you see your air speed in knots. Twenty-two, that’s perfect, right there!. Air speed control is critical. If you get too slow it will stall and too fast it can dive into the ground. It’s just elevator control and hip cradle. When you move the hip cradle, you’re warping the wings to control roll and you’re also getting rudder movement with it. Jennifer PulleyWell, it took some practise, and it wasn’t real comfortable but I think I got the hip thing and the elevator thing going, I was finally able to make a glide that lasted about 63 seconds.
Thank
you so much, Bill.
Bill HaddenYou’re welcome.
Ken Hyde
Well, how was it Jennifer? Jennifer PulleyOh, Ken, it was incredible! I’ll tell you it was a little uncomfortable and it was kind of difficult to maneuver but I can really relate to how the Wright Brothers must have felt . They must have had a lot of stamina in order to be able to do this.
Ken HydeThey sure did! And this 1902 glider all their innovations are in this machine. It’s what they were striving for. By 1903, the Wrights were ready to add an engine and propellers. The Wright brothers’ breakthrough in propeller design came when they realized that a propeller was merely a wing in rotation in a helical pattern— creating lift in a forward direction. Once they saw the propeller in this way, they were able to use their wind tunnel data about lift and drag to design an efficient propeller. Jennifer, we also have a simulator of the 1903 Kitty Hawk Flyer. Would you like to fly this machine? Jennifer PulleyOf course I would, Ken! Now, while I’m trying out the 1903 Flyer simulator, why don’t you check out how to build your own flying machine and test its performance? StudentHi! We’re students at Dunseith Indian Day School here at the Turtle Mountain Reservation in North Dakota! StudentIn ancient America, our ancestors dreamt of flight … …and we celebrate this dream through our dances and
stories because American Indians have always been fascinated by the flight
of the powerful eagle and the graceful butterfly. StudentNASA CONNECT asked Dunseith Indian Day School to show you this program’s hands-on activity. Student
You can download the lesson guide and a list of materials from the NASA Connect web site. StudentHere are the main objectives! Dan GeroeStudents will
- Predict the effect of kite sail area on kite flight.
- Measure the base and height of a kite - Use reflections to create kites - Calculate area of a Trapezoid - Calculate aspect ratio - Understand how early flight was influenced by kites StudentHere are some terms you will need to know! Dan
Geroe The Span of a kite is the widest distance from side to side. Aspect ratio is the ratio of the square of the span to the area of the kite. Drag is a force that pushes against an object and slows it down. Lift –is the aerodynamic force that holds an
airplane in the air
TeacherGood morning class. Today, NASA has asked us to investigate the size of kite sails to determine how area and aspect ratio influence flight efficiency.
Dan Geroe
Three kites will be built using different measurements as outlined in the lesson guide. First, hold the long end of a piece of 8 and a half by 11 sheet of paper and fold it in half. Starting at the fold, measure 3.5cm along the top of the paper and mark point A. Now measure 9 cm along the bottom of the paper, measuring from the fold. Mark point B. Draw line segment AB. Reflect line segment AB across the fold line. Call the reflection of point A: A-prime and the reflection of point B: B-prime. Draw line segment A’ B’. Fold back along line segments AB and line A’B’ forming the kite shape’. Place a piece of tape firmly where line segment AB and A’B’ meet. Place a skewer stick along the span of the kite and tape down firmly along the entire length of the skewer stick. Cut off any excess.
Tape a kite tail to the bottom of the kite sail where point B meets point B’. Starting at the top of the flap which is labeled point F, measure 7cm down along the flap and 1 cm in from the fold. Mark and label point E then punch a hole at point E. All measurements will be recorded onto the worksheet. You will calculate and record the kite sail area using the given formula: Area equals one half the height times the sum of b sub one and b sub two. Where h is the height and b sub one and b sub two are the bases. Remember to multiply the value by 2 to calculate the sail area. You will also calculate and record the aspect ratio using the formula AR equals S squared divided by A, where S is the kite span and A is the kite sail area. Tie one end of the string to the hole and wind the other end onto the cardboard string winder. For the other two kites repeat the same steps adjusting
the given values for point A and point B found in the Educator’s
Guide.
Remember your reflections! Once you have completed your calculations, it is time to proceed to the outdoor test flight! TeacherTeams! Are your ready? Let’s let them fly!!! Dan GeroePerform two trials for each kite, rotating student roles until all three kites have completed their two trials. TeacherThere are two questions that we need to answer:
How did the surface of the kite affect its flight? And, was this affect signicant? Roger! RogerThe smaller kite didn’t have enough space here - surface area. This flew just right, had enough surface area. This did too much acrobatics
TeacherWhat other factors could be changed to investigate the effects on kite flight? Josh? JoshWeather, wind, tail, surface area and weight? Dan GeroeWhen you complete this activity, discuss what improvements you would make to your design. A helpful tool is the Interactive Kite Modeler from NASA-Glenn Research Center. On this web site you can study the physics and math which describe the flight of a kite. You can choose from several types of kites and change the shape, size, and materials to produce your own design. By selecting the “Field” button, the kite flies with the control line running from you to the kite. This view is recommended during the "Flight" phase of your kite. Depending upon your choice, different variables are shown. The values of these variables are shown on the output panel. The Kite Modeler tells you if your design is stable or not and also computes a prediction of how high your kite will fly. Teachers, if you would like help to perform the preceding kite building lesson, simply enlist the help of an AIAA Mentor who will be glad to assist your class in these activities! AIAA stands for the American Institute of Aeronautics and Astronautics.
Jennifer Pulley Wow, Ken, this simulator for the 1903 Flyer is so different
from the simulator for the 1902 flyer! Ken
Hyde
It
really is.
Jennifer
Pulley
Thank you so much. Okay.,
let’s review! So far, we’ve seen how civilizations throughout
history have dreamt of flight.
We’ve
seen how the Engineering Method can be useful for solving complex problems
and making dreams a reality.
And
you’ve applied a bit of the engineering method yourself by building
kites and evaluating their performance.
So
what is all this have to do with NASA today?
Well, Anna McGowan at NASA Langley Research Center in Hampton,
VA has the scoop.
Students
How
Can Biology be helpful in designing aircraft?
What
is the relationship between pressure and force?
Why
are computers simulations important in the aircraft design process?
Anna
McGowan
The
Wright Brothers discovered ways to sustain controlled flight.
Today at NASA the challenge is to research ways to make flight
safer and more efficient.
One
piece of research NASA is doing is called the Morphing Project.
The Morphing Project is part of the next generation of breakthrough
vehicle technologies. It’s
about designing the airplane of tomorrow and changing the world again
in the process much like the Wright Brothers invention changed the world
they lived in.
We
got the word morphing from the word metamorphosis. The word
morph means to change. And we're using a lot of advanced materials
and technologies to research how to make airplanes change from one configuration
to the other.
That’s what engineers and scientists
in NASA’s morphing project are trying to do—transform the
future of flight.
Student
How
are you transforming the future of flight?
Anna
McGowan
That’s
a great question. The Wright brothers were inspired by watching
birds soar..
…and
they designed their airplanes with wings that could manipulate the wind. The Wrights didn’t use flaps on their machines like airplanes
have today. In the Morphing
project, we are working on making airplanes as versatile as a bird is.
So we’re taking some lessons learned from nature, just like
the Wright Brothers did.
We
are researching and testing many advanced technologies.
One area is called “smart” materials.
We
call these materials “smart” materials because unlike traditional
materials, these materials actually move when you apply a stimulus like
voltage or heat. They are similar to muscle tissue in this
way. So, instead of using
complicated mechanic gears to move or control parts of future airplanes,
NASA is looking at using these smart materials as future control devices
on airplanes.
Another advanced technology that we are studying is called
adaptive structures. In
studying the structures for future flight, we actually are looking at
technologies that can change the shape of parts of the wing during flight.
Student
Why
do you want to change the shape of the wings during flight?
Anna
McGowan
Well,
all wings must be able to adapt to different flight conditions.
Birds do this by gently bending and twisting their wings while they fly. In today’s airplanes, we’re using flaps and slats to adjust the wings to different flight conditions. In the future, we are hoping to enable wings to gently change shape in many different ways, similar to birds. This is one example of an adaptive structure we are working on. This wing changes shape for different flight conditions. It’s designed very different than from today’s airplane wings. Today’s airplane wings are typically hollow to hold fuel and they are also very stiff. This adaptive wing instead has a center spine to carry most of the aerodynamic load and moveable ribs to change shape during flight. We design airplane wings using the principle of pressure. The following algebraic equation should help you understand this principle. Pressure is defined as the Force divided by the area over which the force acts. The force in this case is the aerodynamic load. Have you ever popped a balloon with a nail? It’s pretty easy to pop the balloon
with one nail because the force applied to the balloon is acting over
a very small area - only the head of the nail. This means very large pressure. Now if you try to pop the same balloon with a bed of nails
applying the same amount of force, you notice the balloon is very difficult
to pop.
Student
Why
is that?
Anna
McGowan
Because the area of the bed of nails is much larger than the area of the single nail. If we refer back to the equation for pressure, to keep the same force applied but increase the area, pressure actually becomes much lower. With this adaptive wing, we want to make sure the force or aerodynamic load is distributed evenly across the wing, preventing the wing from breaking.
We
actually call this adaptive wing, here, “the Fishbone” wing
because it resembles the spine and ribs of a fish.
To
understand and design the fishbone wing, the engineers here at NASA use
advanced computer simulations.
These computer simulations help us understand the mechanics of the fishbone wing and tell us how the wing will perform in real life.
We
are even looking at new ways to control the airflow over the wings of
future airplanes.
The
study of air flow is called aerodynamics and today’s airplanes use
large flaps to control aerodynamics.
For future airplanes we are developing technologies that use very
small devices to control the airflow on airplanes – we call this
micro-flow control. For example, tiny fluctuating jets that create a small plume
of air on the surface of the wing can be used to make the flow smoother
and less turbulent - and
this reduces drag. By reducing
drag we can save on fuel costs and also reduce the amount of pollution
coming from the airplane engines.
Here
is an example of one of these jets. This device would suck in air and
blow out air very rapidly to control the airflow over the wing.
Now, several of these devices would be placed in a wing to control
the airflow over an entire wing.
Even
this example is similar to how a bird flies.
In addition to twisting and bending their wings in flight, birds
also rely on their feathers to adjust the airflow over their wings.
Finally
we are applying the principle of biomimetics in the Morphing project.
Student
Bio
what?
Anna
McGowan
Biomimetics
is the abstraction of good design from nature.
In other words, we look at how nature works for maximum achievement
at minimal effort.
…
Today we are even examining the shape of fish fins because, in a way,
fish are ‘flying’ through the water.
Here are several examples of different fish fins that we are
studying. We actually
work with marine biologists to understand how the fish swim and how they
are really efficient flyers.
We
also study seagulls.
Seagulls
can soar really well and their unique wing shape is one of the many reasons
they fly so efficiently. Here is an example of a wing that we would
actually design for wind tunnel testing.
We
call this the “hyper-elliptical cambered span” because of
the really unique shape and because we used ellipses to design this wing.
In the Morphing Project, we take lessons learned not only from biology but we also use
a lot of advanced technologies, new math, new approaches and new science
to really make future airplanes even safer than they are today. We
also want to make them more capable and able to fly in new and different
ways.
We
also want to make them more efficient to help with pollution and also
reduce the cost of flying .
NASA’s Morphing Project is looking to the future and
trying to transform the future of flight.
Jennifer
Pulley
Thanks,
Anna! Now it’s time for a cue card review!
1) How Can Biology be helpful in designing aircraft? 2) What is the relationship between pressure and force? 3)
Why are computers simulations important in the aircraft design process?
If you’re watching this on videotape, you’ll want to pause the tape to discuss these questions…… Okay,
did you get all that?
So
far, we’ve seen how the Wright Brothers began powered flight for
humans and we’ve seen how NASA is working to apply some of the early
principles of Flight which the Wright Brothers perfected.
You know, aeronautics has seen a lot of changes in the last 100
years. Let’s go see Dan Geroe at his web
Domain
Dan
Geroe
Hi and welcome to my domain! The U.S. Centennial of Flight Commission was created by the U.S. Congress to serve as a national and international source of information about activities to commemorate the centennial of the first powered flight. On this site you can learn about America’s plans for celebrating the 100th anniversary of the first Wright Brother flight! Check out the Sights and Sounds Section where you’ll see pictures and download movies… There are hot links to cool web sites about aeronautics and astronautics. This site is a repository for many things related to the Wrights. For Educators, there are several links to activities that encourage educators and students to explore the Wright Brothers flight experiments and to research, plan, and participate in your own centennial of flight activities and events. There are also cool downloads for posters featuring famous “firsts” and spectacular images from aviation history to the present day. Back to you, Jennifer! Jennifer PulleyWell, that wraps up another episode of NASA CONNECT! We’d like to thank everyone who helped make this program possible! Got a comment, question or suggestion? Email them to connect@larc.nasa.gov. Or pick up a pen and mail them
to
NASA CONNECT NASA’s Center for Distance Learning NASA
Langley Research Center Mail Stop 400 Hampton, VA 23681 Teachers, if you would like a videotape of this program and the accompanying lesson guide, check out the NASA CONNECT web site. So, until next time, stay connected to Math, Science, Technology, and NASA! See you then! |
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