Transcript for NASA Connect - Proportionality - The X-Plane Generation

[00:00:13.349]
[ Music ]

[00:00:13.489]
[Collins] Hi.

[00:00:14.329]
I'm astronaut Eileen Collins.

[00:00:16.419]
You may remember me as
the first woman to pilot

[00:00:18.909]
and to be named a space
shuttle commander.

[00:00:20.999]
You know, when I was a
child, I dreamed about space.

[00:00:24.149]
I knew that I'd have to study
math and science if I wanted

[00:00:26.869]
to become an explorer myself.

[00:00:30.119]
In today's episode of NASA Connect,
you will see how NASA engineers

[00:00:34.179]
and scientists are using a
math and science to build

[00:00:37.469]
and test scale models
of spacecraft.

[00:00:40.119]
You will also get to
make your own model

[00:00:42.029]
of the NASA spacecraft
using your knowledge

[00:00:44.479]
of ratios and proportions.

[00:00:46.689]
So hang on as hosts Dan Hughes
and Jennifer Poli connect you

[00:00:51.359]
to the world of math,
science, and technology

[00:00:55.889]
on this episode of NASA Connect.

[00:01:04.889]
[00:01:25.979]
[ Music ]

[00:01:26.979]
[00:01:29.949]
[Jennifer] Take it
easy, take it easy.

[00:01:32.369]
Are you all right?

[00:01:33.039]
[Dan] No. This is terrible.

[00:01:34.659]
[Jennifer] What's the matter, Dan?

[00:01:36.129]
And why did you insist that
I meet you here on a bicycle?

[00:01:39.879]
[Dan] Come on, we
haven't time to lose.

[00:01:42.689]
[Jennifer] Wait a minute.

[00:01:43.059]
Dan, Dan! Let me just see
if I've got this straight.

[00:01:46.919]
You've come to Huntsville
Alabama to go to space,

[00:01:49.779]
but decided you will show up days
early to be in a 20 mile bike race?

[00:01:54.239]
[Dan] No, Jennifer.

[00:01:54.889]
It's a 25 mile bike race.

[00:01:57.539]
[Jennifer] I never knew
that you raced bikes.

[00:01:59.229]
[Dan] I didn't either.

[00:02:00.839]
I mean, I never have.

[00:02:02.359]
I'm exhausted.

[00:02:03.169]
What was I thinking?

[00:02:05.099]
I'm sure to lose.

[00:02:07.299]
[00:02:08.629]
[Jennifer] Well, can't
you just withdraw?

[00:02:11.299]
If you like, you can go

[00:02:12.429]
to the outdoor sports
conference that I'm attending.

[00:02:14.689]
I'm sure you'll find the
speakers and sports fascinating.

[00:02:17.289]
They'll even discuss bike racing.

[00:02:19.349]
I know. We'll train
again next fall,

[00:02:21.219]
and sign up to race next year.

[00:02:23.409]
[Dan] No. I feel obligated.

[00:02:25.499]
And besides, the entry
fee is nonrefundable.

[00:02:29.079]
[Jennifer] Okay, so
you are committed.

[00:02:30.729]
But why the negative attitude?

[00:02:32.169]
I mean a damn, you
could win this race.

[00:02:34.729]
[Dan] You're right.

[00:02:35.459]
Based on the one-mile test run I
did this morning, I may be destined

[00:02:39.319]
to enter the record books as
the worst bike racer ever.

[00:02:43.489]
[Jennifer] Well, the one-mile
test run was a great idea.

[00:02:46.369]
And you know, I have friends at
NASA Marshal Space Flight Center

[00:02:49.759]
in Huntsville, Alabama.

[00:02:51.139]
They conduct tests on their
vehicles before flying them.

[00:02:53.819]
And who knows, maybe --

[00:02:55.189]
[Dan] Are you saying that I should
get a rocket engine put on my bike?

[00:02:58.729]
[Jennifer] Not exactly, relax.

[00:02:59.979]
Come on. It's downhill
most of the way.

[00:03:02.489]
[Dan] OK. Let me get
some energy, some food,

[00:03:04.739]
my energy is running low as well.

[00:03:06.109]
[Jennifer] All right.

[00:03:06.769]
While you're doing that, why
don't we meet back at the US Space

[00:03:09.949]
and Rocket Center in,
say, about an hour.

[00:03:11.899]
And then we'll go there.

[00:03:13.049]
[Dan] All right.

[00:03:13.839]
[Jennifer] Meanwhile,
let's head over to one

[00:03:15.559]
of NASA's research
partners, the University

[00:03:17.729]
of Alabama at Huntsville.

[00:03:19.329]
Dr. Clark

[00:03:20.229]
[unclear], a professor

[00:03:21.329]
at the university's propulsion
research center is there waiting

[00:03:25.379]
to tell us more information
on energy and motion.

[00:03:29.069]
[Clark] Energy and motion are found

[00:03:31.359]
in common everyday
things we find around us.

[00:03:33.989]
Energy is the capacity for doing
work, and motion is the term we use

[00:03:37.459]
to describe things moving
from one place to another.

[00:03:40.219]
I can illustrate energy and its
transformation using this ball.

[00:03:43.739]
I put work in by raising it up
to this height above my head,

[00:03:47.459]
and then I transformed into energy
of motion as I let go of it.

[00:03:52.889]
Now we'll go over to our
propulsion test facility,

[00:03:55.159]
and meet with engineering
student Melanie Janetka.

[00:03:58.369]
[00:04:00.809]
[Melanie] What we do here
is test small-scale versions

[00:04:02.869]
of rocket engines to see how the
real ones will behave in flight.

[00:04:06.219]
That's a whole idea
behind proportionality.

[00:04:08.599]
And doing it this way makes
space transportation safer,

[00:04:11.359]
more affordable, and more reliable.

[00:04:13.739]
By taking his bike on a test run,

[00:04:15.399]
Dan was able to see how his bike
would perform in an actual race.

[00:04:18.989]
Proportionality is
the use of ratios.

[00:04:21.679]
In other words, this engine is

[00:04:23.309]
about 2000 times smaller
than the real thing.

[00:04:26.709]
Dan's test run was 25 times shorter

[00:04:29.139]
than the distance he
will travel in the race.

[00:04:31.149]
Proportionality is
used for everything.

[00:04:33.709]
That includes art,
cooking, and architecture.

[00:04:37.319]
[Clark] When we are designing

[00:04:38.099]
and testing state-of-the-art
multimillion dollar stadiums,

[00:04:44.389]
there are several steps we must
take even before ground can

[00:04:47.019]
be broken.

[00:04:48.039]
One of those steps is
to build the stadium,

[00:04:50.279]
but on a much smaller scale.

[00:04:52.169]
We called this proportionality.

[00:04:53.919]
It's the use of ratios
like 1:100 in scales

[00:04:56.799]
in order to meet challenges.

[00:04:58.439]
It's nothing new.

[00:04:59.619]
It's likely the Egyptians used this
to help build the great Pyramids,

[00:05:03.399]
and the Romans to help
construct the Coliseum.

[00:05:06.459]
Today, proportionality
is used everywhere.

[00:05:08.849]
NASA even uses this to help
construct future spacecraft.

[00:05:12.509]
This is a scale model of
the Raymond James Stadium,

[00:05:15.279]
home of the Tampa Bay Buccaneers.

[00:05:17.339]
Every inch here was 100 feet or
1200 inches of the real thing.

[00:05:23.209]
A lot of this goes
back to math class.

[00:05:26.509]
It's all about proportion
and scaling things.

[00:05:30.809]
We pay close attention to the
relationship between sizes.

[00:05:39.809]
[00:05:43.389]
[ Music ]

[00:05:43.389]
[Voices] Unclear.

[00:05:44.669]
How would a test engineer
use computation?

[00:05:47.909]
[Melanie] Force is the capacity to
do work or cause a physical change.

[00:05:52.729]
Now that was the force
of gravity at work.

[00:05:55.579]
The work that we're doing
here deals with propulsion.

[00:05:57.609]
We are developing ways to overcome
the force of Earth's gravity.

[00:06:02.079]
Unclear is the power of
available for us to use.

[00:06:04.939]
We get our energy by fueling
our bodies with healthy foods.

[00:06:08.539]
When we ride our bikes, our human
body is a machine that propels it.

[00:06:12.589]
Rockets carry their own
propellants as an energy source.

[00:06:15.929]
The proponents are
burned in the engine,

[00:06:17.619]
which provides the force
needed to reach Earth orbit.

[00:06:20.529]
Last but not least is
calculating, or computation.

[00:06:24.269]
Simply put, that's working with
numbers to make them work for us.

[00:06:28.689]
We use computation before, during,
and after these rocket tests.

[00:06:32.959]
All of these concepts can be and
are perceived in our everyday lives

[00:06:36.399]
with all sorts of problems.

[00:06:37.839]
[Jennifer] Mike, how do you
get ready for a bike race?

[00:06:46.719]
Hey John. Thanks for meeting us.

[00:06:48.389]
This is my friend

[00:06:49.239]
[Dan]

[00:06:49.439]
[Voice] Hi Dan and Jennifer.

[00:06:51.099]
I'd like to welcome both of you
to the Marshal Space Flight Center

[00:06:54.629]
and to our historic test area.

[00:06:57.179]
Dan, we understand that you're
involved in a bike race.

[00:06:59.869]
And in any race, it's
important to understand

[00:07:02.069]
where you've been before you
figure out where you're going.

[00:07:04.829]
[Jennifer] Some pretty historic
boosters tested right here

[00:07:07.329]
in these test areas.

[00:07:09.169]
The measurements taken here
on the ground were used

[00:07:11.459]
to calculate how the real
thing would operate in flight.

[00:07:14.619]
What they did was some
truly amazing things.

[00:07:17.839]
You know, it wasn't that long ago
that people talked about something

[00:07:20.969]
that was impossible to do, they'd
say, you've got as good a chance

[00:07:24.589]
of doing that as going to the moon.

[00:07:28.579]
[Recording] Tranquility Base here.

[00:07:31.109]
The eagle has landed.

[00:07:33.069]
[Jennifer] I bet NASA doesn't
hear that one too much anymore.

[00:07:34.959]
[Laughter]

[00:07:34.959]
[Dan] You know, this
is really cool.

[00:07:36.769]
But how can it all be related to
my problem with the bike race?

[00:07:40.449]
[Voice] Well, Dan, let's take
a look at what NASA is doing

[00:07:42.179]
in its next generation X plane,

[00:07:43.999]
which in part is being
tested right in this area.

[00:07:46.749]
[Dan] What is an X plane?

[00:07:48.039]
[Voice] Dan, an X plane is an
experimental aircraft built

[00:07:53.539]
specifically for research purposes.

[00:07:55.599]
This is one of the latest explains.

[00:07:56.969]
It's called the X-33.

[00:07:59.079]
This is a 1:50 scale model of the
X-33, which itself is a scale model

[00:08:03.159]
of what we're ultimately
after, which is a single stage

[00:08:05.749]
to orbit reusable launch vehicle

[00:08:07.899]
that Lockheed Martin
refers to as Venture Star.

[00:08:16.359]
[Music]

[00:08:17.709]
[Voice] What is a thermal
protection system or TPS?

[00:08:21.459]
[Voice] Name two examples
of thermal protection.

[00:08:25.859]
[Voice] The X-33 demonstrator
will fly and test

[00:08:28.719]
out the technology used in it to
make going into space more common

[00:08:31.819]
by making it more
affordable and more reliable.

[00:08:34.599]
It takes off vertically
like a rocket

[00:08:36.369]
and lands horizontally
like an airplane.

[00:08:38.799]
The X-33 was designed
with advanced hardware

[00:08:41.449]
that will dramatically increase
launch vehicle reliability.

[00:08:44.209]
The vehicle is designed to reach
altitudes of 60 miles and travel

[00:08:48.069]
at velocities up to 13
times the speed of sound.

[00:08:51.079]
[Dan] What do you
mean by velocities?

[00:08:53.609]
[Voice] Velocity is simply the
speed at which something is moving.

[00:08:56.689]
Try hitting the atmosphere when
you are moving at super velocity,

[00:08:59.669]
and the friction of air molecules

[00:09:01.289]
with the spacecraft become
like sandpaper to a match.

[00:09:06.389]
A thermal protection system,
or TPS, keeps spacecraft

[00:09:09.719]
from burning off when it comes back

[00:09:11.419]
into the atmosphere
on the journey home.

[00:09:13.469]
[Dan] OK. So the X-33 has to
be protected from the heat.

[00:09:17.089]
But can a TPS be used to
protect something from a cold,

[00:09:20.389]
like maybe a special
outfit for me to wear

[00:09:22.239]
so I don't freeze during
this winter bike race?

[00:09:24.219]
[Voice] Yes.

[00:09:24.319]
Some of them are being used
in down to earth applications.

[00:09:27.349]
To keep homes and people protected

[00:09:29.259]
from temperature extremes,
both hot and cold.

[00:09:32.369]
[Voice] Portions of the
X-33 TPS system were tested

[00:09:34.849]
on a high-performance jet at the
NASA Dryden Flight Research Center,

[00:09:38.769]
and also in special
wind tunnel tests

[00:09:40.719]
at the NASA Langley Research Center

[00:09:42.129]
and at the NASA Ames
Research Center.

[00:09:44.999]
[Dan] I just had a small-scale
test with my 1 mile bike ride.

[00:09:48.399]
[Voice] That's right.

[00:09:48.979]
Your 1 mile test run was a
much more manageable size

[00:09:51.989]
to test your bike's technology
than the 25 mile race.

[00:09:55.569]
Because of your testing, you'll be
able to change things on the bike

[00:09:58.759]
and retest more easily.

[00:10:00.169]
[Jennifer] Now although
the tests were conducted

[00:10:01.779]
on two different types of
vehicles, your bike and the X-33,

[00:10:05.989]
they basically serve
the same purpose.

[00:10:08.239]
They use math and science
concepts to overcome challenges.

[00:10:11.829]
OK, Dan, so tell me, what have
you learned from your test run?

[00:10:15.009]
[Dan] That I was exhausted.

[00:10:16.539]
The bike is so heavy it was
really hard to pedal up the hills.

[00:10:19.809]
[Voice] That's because it took
an excessive amount of energy

[00:10:22.009]
to propel the vehicle.

[00:10:23.219]
If you multiply the
energy that it took

[00:10:25.139]
to go 1 mile times the 25
you'll need from the race,

[00:10:28.949]
you can see there's a problem.

[00:10:30.359]
[Voice] I see what you're saying.

[00:10:31.379]
Hey, let's figure it
out mathematically.

[00:10:32.749]
[Voice] OK.

[00:10:33.439]
How can a one-mile bike ride
tell us what a 25 mile bike race

[00:10:39.719]
will require?

[00:10:40.519]
Enter the world-famous ratio.

[00:10:44.099]
The ratio is a way of comparing
the size of two numbers.

[00:10:48.029]
Let's compare Dan's 1 mile test run

[00:10:50.709]
to the 25 mile bike
race he will enter.

[00:10:57.259]
Now, ratios can be
written in numerous ways.

[00:11:00.289]
Like that, or even like that.

[00:11:07.599]
Now all of these ratios are
read the exact same way.

[00:11:10.649]
They are all read 1 to 25.

[00:11:13.149]
Notice ratios can also
be written as a fraction.

[00:11:16.369]
Got it? So, for every
one of whatever it took

[00:11:21.119]
for Dan's test ride,
it will take 25 times

[00:11:24.879]
that in order to complete the race.

[00:11:27.429]
For example, let's
say Dan has to pedal

[00:11:30.749]
on average 1500 revolutions
to go that 1 mile.

[00:11:34.619]
Can you estimate how many
revolutions he can expect to pedal

[00:11:38.279]
in order to complete the race?

[00:11:40.119]
One way to solve this ratio
is to use the fraction ratio

[00:11:43.539]
and set it up like this.

[00:11:45.619]
1 mile to 25 miles equals
1500 revolutions to, what?

[00:11:52.849]
I mean, what number
can you put here

[00:11:55.579]
so that this second
fraction equals 1 to 25?

[00:12:02.299]
It's easy.

[00:12:03.369]
If you multiply 25
times 1500 revolutions,

[00:12:07.729]
that equals, 37,500 revolutions.

[00:12:15.509]
In order for him to complete
the 25 mile bike race,

[00:12:19.019]
he will have to pedal
approximately 37,500 revolutions.

[00:12:24.389]
Better him than me.

[00:12:26.979]
Of course, there are better
ways to solve this ratio.

[00:12:30.589]
What method did you use?

[00:12:38.159]
[ Music ]

[00:12:38.619]
[Voice] How can you improve
the performance of a bicycle?

[00:12:44.649]
[Voice] Explain two
forces that both X plane

[00:12:47.689]
and the bike's performance

[00:12:49.689]
and could you tell us how
they relate to each other?

[00:12:52.409]
[Voice] OK.

[00:12:53.179]
So we've collected the
baseline information

[00:12:55.409]
from Dan's 1 mile test run.

[00:12:57.199]
I think we can all agree that
some improvements need to be made.

[00:13:00.309]
And obviously we can't
change the size of the bike,

[00:13:03.069]
but I mean can't we improve some

[00:13:05.509]
of the bikes technologies
or something?

[00:13:07.059]
[Dan] Yes.

[00:13:07.239]
Make it lighter so it's
easier to pedal or something.

[00:13:09.819]
[Voice] Right.

[00:13:10.329]
You can decrease the force
it will take to pedal

[00:13:12.369]
by decreasing the
weight of the bike.

[00:13:14.199]
One way that you can do it is
to replace the frame with one

[00:13:17.579]
that is made of a new lighter
stronger composite material instead

[00:13:21.879]
of this heavy steel.

[00:13:22.969]
That's something that we
had to do with the X-33.

[00:13:25.679]
[Voice] And we already learned
from our subscale testing

[00:13:28.029]
that both the X-33 in the larger
Venture Star are going to need

[00:13:31.669]
to use composite materials
in order for both

[00:13:33.859]
of them to reach space.

[00:13:35.209]
[Voice] You know, it seems to me
that some of Dan's struggle was

[00:13:38.479]
with poor aerodynamics.

[00:13:40.779]
[Voice] That's another problem
the X-33 and the bike share.

[00:13:44.169]
Moving through the air easily
and with less resistance.

[00:13:47.219]
A lot of this has to
do with the geometry,

[00:13:49.609]
so the shape of the
vehicle is critical.

[00:13:51.679]
The X-33 has a wedge-shaped design.

[00:13:54.629]
I suggest you look for ways to
make the bike more aerodynamic.

[00:13:58.069]
Otherwise, you're just
fighting the force of drag.

[00:14:01.199]
Drag is simply the resistance
of an object caused by the air,

[00:14:04.169]
in this case, through
which it is moving.

[00:14:05.689]
[ Voice ]

[00:14:06.329]
Yes. Since X-33 is
a flying machine,

[00:14:08.599]
we also need to generate lift.

[00:14:10.459]
That is the force
that supports objects

[00:14:12.189]
as they move through the air.

[00:14:13.509]
[Dan] Well, you can't test
that with a test run like mine.

[00:14:16.719]
[Voice] No, but we can
simulate it on the computer.

[00:14:19.389]
And we can run small-scale
models in the wind tunnel.

[00:14:24.109]
[Dan] Oh, OK.

[00:14:24.419]
So we can make the bike less
resistant to air and gravity,

[00:14:29.069]
but what else can we do?

[00:14:30.729]
[ Voice ]

[00:14:30.859]
One thing you can do is you
can make the power source

[00:14:33.009]
more efficient.

[00:14:34.179]
Now on the bike, you
are the engine.

[00:14:36.609]
Are you sure you're using
the gears correctly?

[00:14:38.939]
[Dan] No, I don't even
know how they work.

[00:14:40.579]
I normally just keep it in third.

[00:14:42.269]
[Voice] Well, let me
show you how they work.

[00:14:43.789]
It's really easy and it'll
make you a lot more efficient.

[00:14:46.769]
[Voice] Well, damn, those
gears are there for a reason.

[00:14:49.809]
See, when you are writing or racing
bikes, you want to use your energy

[00:14:53.399]
as efficiently as possible.

[00:14:55.239]
To do this, you need to
use your gears correctly.

[00:14:58.189]
They will help you pedal at the
same rate throughout the race,

[00:15:01.029]
and help preserve your energy.

[00:15:02.939]
For instance, when biking
uphill, use a low gear.

[00:15:06.219]
And when biking downhill or on
a flat road, use a higher gear.

[00:15:11.019]
[Voice] Like the gears
on your bike,

[00:15:12.349]
the X-33 will also
make efficient use

[00:15:14.809]
of the environment it's
traveling through by using

[00:15:17.449]
to revolutionary linear

[00:15:18.979]
[unclear] engines.

[00:15:19.329]
[Voice] That's so cool.

[00:15:21.889]
Hey, let's head to
Cookville, Tennessee.

[00:15:23.959]
There we are going
to meet some students

[00:15:25.269]
who are making their
own models of the X-33.

[00:15:27.839]
[Voices] Welcome to Prescott
Central Middle School

[00:15:32.559]
in Louisville, Tennessee.

[00:15:34.729]
NASA Connect asked us to
show you the student activity

[00:15:38.099]
for this program.

[00:15:39.429]
Under the guidance of our
teachers, Marla Weaver, Alicia Ray,

[00:15:43.479]
and Ronny Amos, we will go
through the steps you will use

[00:15:47.579]
to build the paper skin

[00:15:48.839]
of the X-33 advanced
technology demonstrator.

[00:15:51.879]
In this activity, we will
also measure many dimensions

[00:15:55.649]
of the model, compare these
dimensions to the actual dimensions

[00:15:59.239]
of the X-33, and compute
a scale factor.

[00:16:02.679]
To help you understand about
proportionality and X planes,

[00:16:06.809]
go to the NASA Connect web site.

[00:16:09.299]
Mr. Weaver reviewed what the lines
and labels on the patterning.

[00:16:13.779]
Identify the

[00:16:14.639]
[unclear] lines, cut
lines, and alignment dots.

[00:16:18.349]
He also told us about the
parts of the X-33 vehicle.

[00:16:22.529]
Before we begin, here are
the materials you will need

[00:16:25.319]
for the activity.

[00:16:26.889]
Card stock or heavy paper.

[00:16:29.329]
Pencils, scissors, rulers,
glue, and calculators.

[00:16:33.999]
After you've gotten
your material together,

[00:16:37.409]
we will begin the activity by
constructing the X-33 model.

[00:16:42.059]
Cutting, folding, and
assembling the model will take

[00:16:45.609]
at least one full class.

[00:16:47.389]
Or about 45 minutes.

[00:16:49.399]
Begin cutting out the model
X-33 pattern on sheet one.

[00:16:54.179]
It's important that the cutting and
folding of your X-33 is accurate,

[00:16:58.499]
so that the parts will
fit together and fold

[00:17:00.529]
into an aerodynamic model.

[00:17:03.129]
Please

[00:17:03.429]
[unclear] all the dash
lines, making sure that

[00:17:06.029]
[unclear] lines and
markings are on the inside.

[00:17:09.269]
For results, place a ruler along
the line and hold it down tightly.

[00:17:14.189]
And slide your finger
under the paper and lift it

[00:17:16.799]
up against your ruler.

[00:17:19.369]
Cut the stock for canted
and vertical beams,

[00:17:22.649]
being careful not to cut the

[00:17:24.099]
[unclear] lines.

[00:17:25.519]
Glue tab A at the edge
that says glue A here.

[00:17:30.399]
Repeat for tabs B and C.

[00:17:33.129]
[unclear] and tuck the

[00:17:34.069]
[unclear] into the
front of the X-33,

[00:17:37.619]
and push it in until it stays.

[00:17:40.169]
[Voice] Now you're ready to
cut out the pattern sheet two.

[00:17:44.759]
Unclear along the middle
and fold back the tabs.

[00:17:48.569]
Put the glue on the top part of
the tabs instead of the bottom.

[00:17:52.889]
You can close the rack under

[00:17:55.839]
[unclear] but don't glue it yet.

[00:17:58.279]
Under the back of the X-33.

[00:18:01.339]
Last, cut off the engine,
glue it, and attach it

[00:18:06.249]
to the back of the model.

[00:18:07.769]
Glue your model closed, and now
you are ready for measurements.

[00:18:13.189]
The final measurements
of the full-size X-33.

[00:18:20.679]
Each student should
fill out the data sheet

[00:18:23.239]
by determining the scale
models of the X-33.

[00:18:30.409]
Write the ratio of the
measurements in column D,

[00:18:34.489]
make sure that the
units are the same.

[00:18:37.259]
Using the results, you can now
calculate the scale factor,

[00:18:40.809]
with is the measurement of
a full-size object divided

[00:18:43.769]
by the measurement of the model.

[00:18:45.899]
When all the data is calculated
and entered in column E,

[00:18:48.109]
we are ready to find out
several scale factors

[00:18:50.019]
by adding the scale factors
by adding the scale factors

[00:18:52.969]
in column E and dividing by 3.

[00:18:55.459]
Record your result in the blank.

[00:18:58.109]
Now that we understand the
concept of proportionality,

[00:19:01.099]
we're going to test whether the
model is a true scale model.

[00:19:10.099]
[00:19:10.109]
[Voice] Great job, guys.

[00:19:12.059]
Hey, let's analyze the data by
reviewing the results of activities

[00:19:16.119]
and responding to the
following questions.

[00:19:18.779]
What can you learn
about building a model

[00:19:21.739]
that would be difficult
to learn otherwise?

[00:19:24.719]
How can a model be misleading?

[00:19:28.359]
Pretend the scale factor is 140.

[00:19:32.949]
Now let's apply this scale
factor is a simple problem.

[00:19:36.509]
Decorate the side of your paper
model with the word NASA like this,

[00:19:42.309]
using the scale factor of 140,

[00:19:44.649]
how tall would the
letters be on the X-33?

[00:19:47.729]
Are they bigger than you?

[00:19:50.239]
Let's visit NASA's

[00:19:51.449]
[unclear] Space Center
in Mississippi.

[00:19:54.209]
There, NASA scientists
are testing engines

[00:19:57.469]
to make the X-33 more efficient.

[00:20:00.999]
The difference between the linear

[00:20:02.479]
[unclear] engine and conventional
engines is the shape of the nozzle.

[00:20:07.199]
Conventional engines have a
nozzle that is shaped like a bell.

[00:20:10.499]
And the hot combustion gases
expand along the inner surface

[00:20:13.859]
of this bell.

[00:20:15.249]
However, with the arrows
bike engine, the nozzle is

[00:20:18.309]
that in the shape of
a V called a ramp.

[00:20:21.119]
And the hot combustion gases
expand a long this outer surface.

[00:20:25.279]
This unusual design allows
for more efficient performance

[00:20:30.049]
from the engine, and a more
optimal vehicle design.

[00:20:34.359]
[Voice] Once all the information
is gathered from the various tests,

[00:20:37.729]
it comes time to put
the data to use.

[00:20:46.729]
[00:20:48.809]
[ Music ]

[00:20:49.019]
[Voice] How do engineers use
their models to test their ideas?

[00:20:53.869]
[Voice] What can you
learn from a scale model?

[00:20:57.179]
[Voice] Peter Jennifer and
Dan, welcome to the Skunk Works

[00:20:59.389]
at Palmdale, California.

[00:21:00.979]
This is the location where
we build the X-33 vehicle.

[00:21:04.339]
You can see some of the
parts of the X-33 behind me.

[00:21:07.359]
That's the vertical stabilizer.

[00:21:09.469]
Most parts are mounted in
the back of the vehicle

[00:21:11.709]
to keep it steady during its life.

[00:21:14.379]
You can see here on this scale
model, this model is used

[00:21:19.019]
to evaluate the aerodynamic
performance in a wind tunnel.

[00:21:23.019]
So it is built in exact
proportions to the actual vehicle.

[00:21:27.399]
Now the vehicle is under
construction right here.

[00:21:29.819]
This is the X-33.

[00:21:31.439]
And it is also a proportionate
vehicle.

[00:21:33.609]
It is proportional to a much
larger vehicle called Venture Star.

[00:21:37.999]
Now, we've learned a lot from
proportioning this vehicle.

[00:21:41.339]
We've already changed the
design of Venture Star based

[00:21:43.839]
on what we've learned in the
proportioning exercise on page 73.

[00:21:47.449]
Well, you sure have
seen and heard a lot

[00:21:52.039]
about how proportionality
is used in science.

[00:21:54.429]
Now, bringing it to your computer
desktop is NASA's educational

[00:21:57.979]
technology program manager,
Dr. Shelley Cainwright.

[00:22:00.989]
[Voice] NASA researchers are
constantly testing new technologies

[00:22:06.399]
and designs for X planes.

[00:22:07.869]
Using everything from scale models
to full-sized flying machines

[00:22:10.979]
that carry people, these
researchers evaluate their designs

[00:22:14.249]
by using a basic formula
of building, testing,

[00:22:17.169]
and recording the results.

[00:22:18.889]
I'd like to introduce a class
of eighth-grade students

[00:22:21.299]
from Talladega County Central
High School in Talladega, Alabama.

[00:22:25.129]
They are undertaking
their own investigation

[00:22:27.429]
into proportionality using a
unique model design challenge

[00:22:31.439]
posted at the NASA
Connect web site.

[00:22:33.419]
Let's see what they're doing.

[00:22:35.459]
[Voices] Welcome to Talladega
County Central High School,

[00:22:38.819]
Talladega, Alabama.

[00:22:40.939]
We have been asked by NASA
to ask these questions.

[00:22:44.489]
Can you take a design that
works in one scale and use it

[00:22:48.869]
to design at another scale?

[00:22:50.729]
[Voice] Do you have to change the
design when you change the scale?

[00:22:54.629]
[Unclear] To find out,
we went to Norbert's lab.

[00:22:56.819]
And then went to the National
Langley Research Center kids'

[00:23:00.159]
corner web site.

[00:23:02.199]
We revealed the activity
intro, collected our materials,

[00:23:06.149]
and went to work building with
Egret, a paper airplane model.

[00:23:10.639]
We used the model shop extra
activities to build the Egret

[00:23:14.269]
[unclear].

[00:23:14.549]
We had to come up with ways
to scale up the design plan.

[00:23:19.699]
The term of the

[00:23:20.579]
[unclear] to build
the model airplane.

[00:23:24.989]
[Unclear] and record the result.

[00:23:26.999]
We learned that changing the skill
of a working design is possible.

[00:23:31.229]
[Unclear] revealed some design
problems which were fun to solve.

[00:23:35.189]
We are even planning
to increase the size

[00:23:37.629]
of the model three times
to see what happens.

[00:23:40.549]
We were also able to find
information about aerospace careers

[00:23:44.189]
and to see how NASA uses
models in their research.

[00:23:48.989]
As the students from
Talladega Alabama have learned,

[00:23:51.399]
design and testing scale
models brings its own set

[00:23:54.429]
of unique challenges and questions.

[00:23:56.439]
From Norbert's lab,
viewers can try their hand

[00:23:59.109]
at being a design engineer.

[00:24:01.159]
I encourage our viewers
to visit Norbert's lab

[00:24:03.219]
at the NASA Connect web site.

[00:24:05.029]
And to test their skills
at building the Egret 2X

[00:24:08.029]
and other paper airplane
models that are available

[00:24:10.259]
from a specially created
online aeronautic model shop.

[00:24:15.389]
[Dan] Thank you so
much for your help.

[00:24:17.359]
[Voice] It was our pleasure, Dan.

[00:24:18.489]
I sure hope it helps.

[00:24:19.689]
[Voice] And good luck in the race.

[00:24:20.999]
[Dan] Oh, Thank you guys very much.

[00:24:22.359]
[Jennifer] Thank you guys so much.

[00:24:22.929]
[Dan] Jennifer, get out of the way.

[00:24:23.789]
I've got work to do.

[00:24:24.969]
[Jennifer] Oh my gosh.

[00:24:25.819]
I'd better catch up with
Dan and see what he's

[00:24:27.489]
up to before he gets
into any trouble.

[00:24:29.029]
Dan, Dan, Dan!

[00:24:31.809]
[Jennifer] Wow, Dan, you went out
and bought a bike for this race?

[00:24:36.559]
[Dan] I did not.

[00:24:37.499]
I transformed the old
bike into a lean, mean,

[00:24:41.989]
efficient racing machine.

[00:24:45.119]
[Jennifer] OK down.

[00:24:46.799]
Tell me what you've done
your bike, this incredible.

[00:24:49.659]
[Dan] All right.

[00:24:50.119]
I replaced the old frame
with something lighter.

[00:24:53.239]
But it's still strong.

[00:24:54.919]
I actually figured out
how to work these gears,

[00:24:57.709]
which is the great thing.

[00:24:58.629]
[Jennifer] So you're
not in third gear.

[00:24:59.949]
[Dan] Of course not.

[00:25:00.469]
I'm using them all the time.

[00:25:02.039]
I made the entire bike more
aerodynamic by getting rid

[00:25:04.759]
of these big clunky bags
and using something smaller.

[00:25:07.199]
I'm not carrying around
these shirts.

[00:25:09.519]
[Jennifer] All right.

[00:25:10.619]
So that's what you've
done to the bike.

[00:25:12.249]
What have you done to yourself?

[00:25:14.499]
[Dan] Well, I got an outfit
that you can see today

[00:25:17.629]
to make me more aerodynamic.

[00:25:19.629]
And also this morning, I
ate a very good breakfast

[00:25:22.779]
[unclear] the vehicle.

[00:25:25.169]
I did a 5 mile bike ride.

[00:25:28.429]
It went very well.

[00:25:30.299]
It's proportionately a
fifth of the real race.

[00:25:32.629]
[Jennifer] Gosh, you
sure have learned a lot.

[00:25:34.089]
That's great.

[00:25:36.379]
Show me more about the gears
and show me what else....

[00:25:38.779]
[Dan] Sorry.

[00:25:39.509]
I can't. I've got to
get back to the grind.

[00:25:41.939]
I've got to perfect my bike.

[00:25:43.929]
[Jennifer] All right.

[00:25:44.399]
I'll let you be.

[00:25:45.189]
Well you know what,
good luck in this race.

[00:25:46.979]
Break a leg.

[00:25:47.789]
I mean, win.

[00:25:48.769]
[Dan]

[00:25:48.769]
[Laughter] That's OK.

[00:25:49.899]
[Jennifer] Bye.

[00:25:50.159]
Good luck.

[00:25:51.369]
[Dan] Thanks.

[00:25:51.779]
[ Music ]

[00:25:51.779]
[Voices]

[00:25:52.169]
[Jennifer] Way to go, Dan.

[00:25:57.719]
Well that about finishes up
this episode of NASA Connect.

[00:26:05.829]
But before we go, would like to
thank Marshall Space Flight Center,

[00:26:08.939]
all the NASA researchers,
Lockheed Martin, Peter Frederick,

[00:26:12.749]
Dr. Shelley Cainwright, University
of Alabama at Huntsville,

[00:26:15.949]
and all the middle school
students and teachers

[00:26:17.689]
that helped make this
episode possible.

[00:26:19.449]
Hey, why don't you pick
up a pen or a mouse

[00:26:21.739]
and right as at NASA Connect?

[00:26:23.579]
Dan and I would love to hear your
comments, ideas, and suggestions.

[00:26:27.489]
So here's our address:
NASA Connect.

[00:26:30.479]
NASA Langley Research Center.

[00:26:32.339]
Mail stop 400, Hampton
Virginia, 23681.

[00:26:36.669]
Or pick up your mouse and e-mail
us at connect@edu.LARC.NASA.gov.

[00:26:45.139]
Hey teachers, if you would
like a videotaped copy

[00:26:48.219]
of this NASA Connect show and the
educator's guide lesson plans,

[00:26:52.819]
well then contact CORE,
the NASA central operations

[00:26:56.319]
of resources for educators.

[00:26:58.379]
All this information
and more is located

[00:27:01.299]
on the NASA Connect web site.

[00:27:03.469]