Transcript for NASAConnect - Plane Weather

[Commentator:] NASA's aeronautic
safety program is a program

designed to help pilots
fly their planes safer.

To know where storms are so
they could fly around it.

To be sure they know where other
planes are so they won't crash

with them, to understand
where the ground is

so they won't have
difficult emergency landings.

It will help them
maintain the planes better

so they won't have engine problems.

They won't have cracks in the
wings they won't have electronics

that fail.

It will help them see through
storms and see through the night

and it will make airport
much safer.

[Van:] Hi!

I'm Van Hughes for Connect.

You know it seems everybody is
always talking about the weather.

I mean anyone can easily adapt to
the change in weather conditions.

There are many variables that
help define weather like the sun,

the rain, and even the snow.

But weather can also influence a
lot of things in our everyday life.

In this program you will learn how
weather impacts air transportation

and the actions taken by pilots
and ground operators in preparation

for planes to fly during
inclement weather conditions.

You will see two examples
of NASA and FAA research

that is currently being conducted

to address weather related
air travel concerns.

For example, the F106 behind me
was subjected to lightening strikes

by NASA researchers to study
how lightening impacts air

borne aircrafts.

So that's pretty cool.

In this program you'll
be asked to participate

in the math based problem

and experience first
hand a demonstration

of how weather can
impact air travel.

At any time during this
program when you hear this,

and you see that on the screen
write down the connect web address.

By using an internet accessible
computer you'll be able

to access NASA and the
FAA researchers and hear

from them their perspectives

to questions presented
throughout this program.

You'll also find other
experts highlights including

meteorologists, pilots
and even kids like us.

But for right now, join us as we
began a new season of Connect.

The United State is
subjected to some

of the world's most
diversified weather conditions.

During the course of a normal year
our country may experience plus one

hundred degrees temperatures,
jungle humidity,

negative thirty degrees cold,
severe draught conditions as well

as being the world leader
in tornado activity;

not to mention an occasional
east coast hurricane.

As our transportation system has
expanded so too has our tendency

to commute on a daily basis to
work in the recreational events.

The potential for weather

to complicate our lives is
therefore also increased.

Aviations perhaps more than
other readily available mode

of transportation today
is strongly impacted

by weather conditions.

Did you know that
seventy five percent

of all airport delays
are related to weather?

In 1996, the estimated price tag

for weather related delays
diversions cancellation

and unexpected operating costs
was two point one billion dollars.

The US government invested
approximately eight hundred

and thirty million dollars

in aviation weather
efforts during 1997.

As the magnitude of these numbers
indicate ensuring weather related

safety and efficiency
of flight has economic

and human lifeline applications
to business and travel

in public communities.

Weather has continual impact
on both the safety of aircraft

and flight and the efficiency

of operations throughout the
national aerospace system.

To complicate things even more
air traffic is projected to triple

over the next twenty years.

More planes and people in the air
flying longer distances more often

and as you know weather
delay will mean

with more air traffic
talk about a traffic jam.

How important is weather

to your daily activates, how well
we understands the weather system

and interaction of the various
elements on the daily forecast,

but most of all how might weather

in one location affect your
plane travel to different region.

Today's meteorologists have the
tools and advanced technology

to explain complex weather
phenomena in a way that is simple

to understand; thanks largely
the satellite information

and computer based modeling.

Dennis Smith of weather channel
in Atlanta, Georgia has offered

to explain and help us understand
the fundamentals of weather.


[Dennis Smith:] Thanks Van, as many

of you know the weather channel
provide twenty four hour weather

information both from a national
and international prospective.

Our meteorologists
constantly monitor

and update weather information.

Now today we are going on fly
through some basic weather concepts

and talk a little bit
about winter weather

which can cause some
problems for aircraft.

To explain how our weather
occurs we must first travel

out pass the boundaries

of our atmosphere ninety
three million miles away.

Our sun emits visible
and invisible energy

that we call solar radiation.

Radiation from the sun travels

through the earth's atmosphere
heating the air, the land

and the water it contacts.

The earth surface absorbs much
more radiation in the atmosphere,

this means that the
sun heats the ground

and the ground heats
the atmosphere.

Not all parts of the
earth are warmed equally.

Regions around the equator receive
more concentrated solar radiation

than to area around the
poles; the result is

that the equator is
warmer than the poles.

Temperature differences
also result because land

and water do not absorb
solar radiation equally.

Because air moves warm air and
cold air are constantly mixing

in the atmosphere.

This mixing not only even out
the global temperature contrast,

but results in the various
weather conditions we see everyday.

If solar radiation
penetrates all layers

of the atmosphere then why
does nearly all weather occur

in the lowest layer,
the troposphere?

The troposphere is
warmest near the ground

and cooler the higher you go.

Its temperature pattern is
favorable for the development

of vertical air turns
relatively warm air tends to rise

and relatively cool
air tends to sink.

As warm air rises in the
atmosphere it expands and cools

as air cools clouds can form
and precipitation and fall.

Warm air rising causes
less pressure to be exerted

by the atmosphere lower air
pressure cool air falling causes

more pressure be exerted, high air
pressure as warm and cool air flow

from one region to
another pressure changes

and soak in the weather.

When air pressure falls quickly it
usually means a stormy weather is

approaching that's a result
of low pressure system.

When air pressure rises there
weather typically results;

that's result of a
high pressure system.

Wind is another bi-product
of changing air pressure,

winds flow because of the pressure
differences in the atmosphere.

Air moves from the areas of high
pressure to areas of low pressure,

winds spiral inward toward
low pressure causing a piling

up of air forcing air to
rise and cool forming clouds

and eventually precipitation.

Around high pressure wind
spiral outwork promoting sinking

in and fair weather.

Okay now while you are
surfing of that information,

lets think of something
a little bit more fun.

When you think of winter is
this the picture you see,

snow, snow and more snow.

But there are other types
of winter precipitation.

The type of precipitation of
falls during winter depends

on how warm air moves over
a layer below freezing air.

A good place to start
is with sleet,

sleet is frozen precipitation
falling is ice pellets.

These ice fall ups warm and snow
flakes pass through a thin layer

of warm air and melt, they
refreeze in the ice fall ups

as they fall to another layer of
colder air close to the ground.

Freezing rain is made of
water droplets that fall

to the earth surface and freeze
upon contact with the ground

or objects near the ground.

For freezing rain to
develop cold air close

to the ground needs to be shallow.

The rain doesn't have time
to freeze in the ice pellets

but upon contact with frozen
objects, it turns in the ice.

Snow is frozen precipitation in
the form of six sided ice crystal.

Snow is produced in clouds where
water vapor changes directly

into ice crystals that remain
frozen as they fall to earth.

Snow will fall when
temperature remain below freezing

from the clouds to the ground
or on a very shallow layer

or above freezing air is
present near the ground.

Winter weather can be a
lot of fun to play in,

but it can cause some problems
for us when we try to get out

and travel either by foot, by
car, and especially by air.

Now you have better
understanding of weather,

here is a question for you.

Weather reports of snow are
typically based on visibility.

Snow fall is considered heavy when
an observer cannot see very far

to the flakes, but visibility
is not the critical element

to the meteorologist interested
in your craft operations.

What do you suppose is the
main issue that is considered

and looking at snowfall from
the perspective of aviation?

Back to you Van.

[Van] Thanks Dennis.

We have just seen the
weather channel for people,

but can you believe that airplanes
need their own weather channel.

To tell us more about the aviation
weather channel is Tom Vanmeder

of the Federal Aviation

[Tom] Thanks Van.

Pilots need to have a continual
awareness of the changing nature

of the atmosphere on
their regular flight.

In order to be able to react
to changing weather conditions

in a safe, efficient, and
timely manner; it is the job

of the weather coordinators here

at the FAA's air traffic
control system command centre

to provide aviation
weather information.

The operational aviation decision
makers such as traffic management

and severe weather specialist
here at the command center,

along with the traffic management
units and severe weather specialist

in the field facilities.

While the national weather
service looks at a wide range

of weather conditions.

Information that the weather
coordinators are looking

for as aviation related, such as
icing conditions and thunder storms

that can have a major impact on
the national aerospace system.

Weather phenomena such as thunder
storms, clear air turbulence,

volcanic ash, and severe
icing can cause large portion

of the national aerospace
system to be unusable.

Geographical features and
altitude also have an affect

on aviation weather.

Moisture drawn from the great lakes
can causes light effects no storms

to form on the east side of
the great lakes for the rest

of the Midwest remains clear.

When icing conditions such as
freezing rain occur at an airport,

ice may build up on air craft
wings changing their shape

and adding a considerable amount
of weight to the aircraft.

This change in shape and addition

of weight can cause the
aircraft to be unable to fly.

To counter the effects of icing

at certain airports the airport
may go into deicing status.

Deicing is a slow procedure

in what's the entire aircraft
is spread with the deicing fluid

to remove the ice and temporarily
prevent additional build up because

of the time it takes to deicing
aircraft there is a reduction

in the number of aircraft that
can depart from that airport.

When this happens if a
corresponding reduction

in the arrival traffic is not
made the number of aircraft

on the airport would grow

until there is no longer
any ramp space left in which

to park additional aircraft.

This situation is
known as grid lock.

The traffic management
specialist at the command centre,

monitor the situation at the
air ports and the deicing status

and if necessary will adjust
the arrival flows in order

to accommodate the airports
capacity and prevent it

from going into grid lock.

When icing conditions are lot
impact a large geographical area.

The traffic management specialists

in the command centre
severe weather unit work

with the affected
facilities to develop routes

around the icing conditions.

Aircraft that are not
equipped for flight

in icing conditions may use
these roots or may divert

to another airport to wait until
the icing conditions have passed.

Aircraft's that are equipped for
flight in icing conditions may fly

through the area of desire.

Consider the weather
related condition of icing.

Our icing characteristic are same
everywhere so let me ask you,

how my geographic and
atmosphere features contribute

to icing differences in different
regions of the United States.

So now you know people are the only
one who need a weather channel.

[Shelly:] Consider the
dilemma in working in the field

of meteorology unlike
other science fields

where laboratory test can be
performed under tight controls,

meteorology has no laboratory
accept the vast dynamic

atmosphere outside.

Our friends at the weather channel

and FAA air traffic systems
command centre has helped

demonstrate the science and art
in making weather predications

and decisions that effect us
on the ground and in the air.

Hi I am Shelly Kenley

[inaudible] officer for NASA
and host for the Connect series.

Thus far we haven't given
some basic understanding

of weather fundamentals
and the impact weather have

on aviation operations.

Meteorological conditions
which have been quickly causes

of aviation delays injuries

and accidents include poor
visibility thunder storms,

wind shield or micro-burst, clear
air turbulence, snow storms,

freezing rain and icing.

In today's program you
will hear from leaders

in the federal government
what made aviation safety

and aviation weather
a specific mission.

Central to this is research it's
a key factor in the developmental

and implementation of
new technologies related

to aviations weather and
because of all that you are going

to have the opportunity to
present some unique NASA facilities

and witness the ground breaking
research and as you listen

to the researcher's stories

on their investigations
consider these questions.

What is the relationship
between science and technology?

What is the role of mathematics
and mathematical tools

in scientific inquiry?

What is the value of
collaborations and partnerships

in conducting research?

We have already mentioned the many
types of meteorological conditions

that can effect aviations

for the remaining portion
of this program we are going

to learn our focus
on one type icing.

Icing can have a profound
effect on the in flight

and ground operations
of the aircraft.

Let us visit to NASA research
centers that are involved

in various icing research studies.

We'll start our icing travels by
visiting NASA Louis Research Center

in Cleveland, Ohio and
its Icing Research Tunnel.

Now this facility is the world's
largest refrigerated wind tunnel.

So bundle up, let's go
visit that's a giant cooler

and have a closed look at
icing effects on air craft

and the icing research
been conducted.

Listen to learn how one
measures the effect of ice

on aircraft performance.

[Judy:] Thanks Sherry.

My name is Dr. Judy Van Zante and
I'm standing in the test section

of the Icing Research Tunnel.

Right it's nice and warm in here,

but later on its going
to get really cold.

Alright, what this tunnel was built
for was to stimulate down here

on the ground what is
like when air plane to fly

through an icing cloud up there.

We do this by creating a cloud
that mimics what you see up there.

As one of the research
engineers, I ask the operators

to select by five parameters.

One is the air speed coming pass
the model one is temperature how

cold it is or below freezing.

Two parameters are about the cloud
density, how much water I have

in the cloud density
how big each drop sizes.

The final parameters I select is,

the time that I will be
flying through that cloud.

I select the cloud conditions,

I select the model I
either select an engine

which provides the airplane
forward trust or select a wing

which provides the plane live and
I want to see one of three things.

One is what kind of ice do I grow
on my model what is it look like

for the given cloud condition and
the other thing that want to look

at is how to keep icing growing
on that and ice protection system

and the third thing and
that I want to look at is

to see how well I can predict with
the eye-shape is gonna look flat;

using a mathematical
module and a computer.

All these three functions
are done in the tunnel.

I use this tunnel along with Conrad

[inaudible] for the tail
plane icing program.

We did there was to see how
ice contamination effects the

operations of the tail plane.

Let's take a look at
what the tail plane is

and how it effects
their craft operation.

What we have here is an animation
of an airplane or flight.

The forces acting on this
airplane are the weight which acts

through the centre of gravity.

The upward lift is provided by
the wings and the tail plane

on the right side of the screen
provides a downward lift.

In equilibrium flight we
got the following force

and movement balances to consider,
we've got the weight which acts

through the centre of gravity

which is also the
aircrafts pivot point.

That's always forward of
the wing centre of lift.

Those two forces acting
together create a nose

down pitching movement.

The tail comes in to
provide a downward lift.

As you can see that's a
simple geometry problem.

The plane acts an often
lot like a sea-saw.

The tail plane icing
project that Tom and I worked

on investigated the question
of what happens if you move

that wing centre of
the further back.

How does tail plane if you
got an eye-shape on it.

We NASA Louis

[inaudible] centre took
this information and gave it

to the pilots so they
can make better

and safe operating decisions.

Back to you Shelley.

[Shelley:] Good science
boils down to making as many

of high quality observations
as possible and then analyzing

and interpreting them.

At NASA Langley Research
Centre in Hampton Virginia,

a five year research program
called the Joint Runway friction

measurement program is under way.

This international effort is
investigating aircraft losing

touching on icy runways.

This icing research program is
having some groovy spin offs.

Let's meet with Tom

[inaudible] and learn more
about runaway, runways.

[Tom:] Thanks Shelley.

I am standing here this morning

in our aircraft landing
dynamics facility shop area.

Behind me you can see one of
our test carriages we have got

to display here all the landing
gear system that we are looking

at to evaluate from a standpoint

of reducing the loads
going into the fuselage.

On my right here is a display
showing some of the work

that we have done to support the
shuttle tire program that's started

in the mid-70s and has been
quite successful since then.

We have done several modifications
to the runway down there based

on the research data
that we obtained here

at our aircraft landing dynamics
facility in Hampton ,Virginia.

We've also done work in
modifying the tire design

and the break unit that's used on
the shuttle that's been flown later

on this month from
Kennedy Space Centre.

We do a lot of work,
you are looking

at aircraft set design how
the grooves are positioned

and minimized the hydroplanic
potential can occur,

join aircraft landing and take
off operations on wet runways.

You are doing a typical aircraft
landing your tire touching

down on a contaminated
or ice coverage surface.

And due to the reduced friction
the capability between the tire

and the ice that takes
a considerably long time

for this tire to spin up,
to a spin that's equal

to the forward motion
of the airplane.

We are currently involved in
fourth year of a five year program

with partnership with the
FAA, Transport Canada,

the National Research Counsel of

[inaudible], the National Defense
Department out of Winnipeg as well

as several aviation organizations
supporting this activity

where we are evaluating
aircraft breaking performance

under winter conditions.

These conditions improve
snow, ice, slash and water

and today the majority of the
tests have been taking place

and North Bay on Ontario,
which is about two

and half hours north
of the Toronto.

We have evaluated breaking
performance of the Falcon Twenty

at the Dehavilland
Dash Eight airplane

in FAA Boeing Seven
Two Seven airplane

and a NASA Boeing Seven
Three Seven airplane.

Coming up in this program you'll be
involved in classroom experiment,

that will give you a better
idea of how coefficient

of frication influences
the motion of two objects

for example pavements and
tiers in order to work here

at the track facility we
have identified the fact

that the higher the
friction coefficient,

this short is the stopping
distances for an airplane operating

on a runway and the last chance he
has of going off either the side

or the end of the runway.

Some of equations that determine
this behavior of vehicles operating

on pavement surfaces
will be explain to you

in the classroom experiment and I
want to wish all of you a good luck

in conducting that experiment.

[Shelly:] Just see that the tip

of the iceberg regarding
the amazing research,

researches and research tools.

Make you wonder though whatever new
technologies are under development

for reducing ice in
hazards, but you know what,

now the time to put you to work
coming up is a high school student

who has spent this
summer at NASA Langley

in a nine week mentorship
working closely with Tom


John has prepared a special hangs,
on minds on activity which a group

of students will demonstrated.

Following in the program
you are encouraged

to replicate the same

[John:] I spent nine
weeks in the NASA program

for high school student
called Sharp.

Under this program I had the
opportunity to work with Mr


I learned a great deal about
the research being done

on runway frication, tier designs
and new types of runway services

to minimize bad weather effects.

Aftermath I was little
nervous at to beginning just

because of I wasn't sure if I knew
enough math and science to be able

to graph the research
and to be able help

out in the evaluation
of the research data.

But I did okay I found that math
I had taken in middle school

and high school gave me a good
foundation that I could build on.

But help of two undergraduate
students that I worked

with during the summer
Brian and Jonathan,

I have a simple experiment
that I would like you to try.

In this experiment you will
investigate how surface conditions

influence the coefficient of
friction between to surfaces.

Your surfaces will include
a ruler, sand paper,

and objects found in the classroom.

Now my friends and I did an
experiment similar to the one year

about to do but it is a
little more complicate

and it involves the
little more math.

This experiment has been recreated
on Connect Plane Whether website.

So you might try this
with your friends

or your family following
the program.

Enough said, let's get started,
the math formula you need

in doing your experiments
looks like this.

The friction coefficient close
height divided by length.

[Student:] The final materials
were collected for our experiment;

three matching rulers at least one
of the rulers has to be plastic,

sheet of sand paper large enough
to cover ruler and four objects

to test a rubber eraser, a large
amount of paper clip, plastic


John how does I identified
the dependent

and independent variables
for our experiment.

The independent variable
which is roughly

with the changing is
the ruler surgface.

We used a plastic ruler to
simulate a smooth runway surface

and then it cover some sandpaper,
stimulate a rough on your surface.

The dependent variable
for the experiment was the

classroom object.

Before giving our test we talked

about how each object
was alike and different?

We shared ideas on how the
surface condition, which we --

what why these objects cross
may affect friction force

of each objects.

We have prophesized about the
affect the surface change could

have on the objects.

Here are the test
procedures we followed,

one metric ruler we identified
as the test based enabled

with the number one, it would
be used to measure the line.

A second ruler in label two
was held up right for the test.

We would measure the
height from this ruler.

The third rule labeled
with three was plastic

and will represent the run light.

One person handles
the runway ruler,

one person held the height ruler,
third person is responsible

to the height and base measurements

and the fourth person was
responsible for recording that.

Running our two surface
tests, we were interesting

in collecting the heights
measurement for that vertical ruler

and the length measurement from
the base ruler at the point

when an object began to
slide down the runway ruler..

We tested each object three times
on both smooth and rough surface.

The smooth surface was the
backside of our plastic ruler.

The rough surface was the sand
paper attached to the ruler.

Here is a diagram to show you
how the experiment worked.

Each test object that faces at the
end of a ruler and then one end

of the ruler was slowly raised.

We start raising the ruler one the
object start to slide down the sofa

from one way and then tip our
measurements of height and length.

Now that we have finished
our testing we are ready

to look closely at our data.

First we will calculate the height
and length average for each object

on each of the surface types.

[ Music ]

[Student:] Using these averages
we will apply John's formula

to find the friction coefficient.

That formula as friction
coefficient equals height divided

by length.

Now we are ready to
answer our question.

What affect the surface
conditions have

on the friction coefficient
between two surfaces?

Well, this is our experiment and
we leave you with the challenge;

what other variables can you think
of after testing this experiment?

[Shelly:] Okay gang you've
received your challenge.

Complete your own runway traction
experiment and then do further test

on different surface conditions.

As we bring this program to
close, let me remind you to check

out the Connect website for
responses from a variety of experts

to questions posted
throughout this program.

And also to participate in
an online such an experiment.

Let me slight things to Van
now for some closing comment.

This is Shelly Kenley for Connect,
connecting you with real science

and with real scientist
in near real-time.

Take it away Van.

[Van:] Thanks Shelly, I hope
you know the plain understanding

of plane weather, I
know I assured you.

Join us for other Connect programs.

Simply access or Connect
website for information

and program availability.

So until next time stay CONNECTed.


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