Program Information

Series: NASA Connect
Program: Quieting the Skies
Segment Number: 3 (Watch entire program)
Duration: 00:06:44
Year Produced: 1999
Description:

NASA Connect segment exploring the research and study efforts applied towards acoustics and noise, especially that related to aircraft. The segment also explains the study of psychological effects of noise on people.

NASA CONNECT™ is a series of Emmy®-award-winning, math-focused programs. Each program supports the national math, science, and technology standards and has three components that include (1) a 30-minute television broadcast; (2) a companion educator's guide; and (3) an online activity that further explores topics presented in the broadcast. These programs establish a connection between the math, science, and technology concepts taught in the classroom to those same concepts used everyday by NASA researchers.

For more information visit: http://connect.larc.nasa.gov/

Transcript

OH, GREAT.

YOU'RE JUST IN TIME.

EVERYBODY, LET ME INTRODUCE YOU
TO BRENDA SULLIVAN
AND RICHARD SILCOX.

WE'RE HERE AT NASA LANGLEY
IN A BUILDING WHERE
THEY DO ACOUSTICAL RESEARCH.

LET'S GO HERE FIRST,
TO RICH.

YOU ARE A SENIOR
RESEARCH ENGINEER, RIGHT?

CORRECT.

ALL RIGHT, AND, BRENDA--
HMM, I'M GONNA GET
THIS NAME WRONG.

BRENDA, YOU ARE
A PSYCHOACOUSTICIAN.

NO, CAN YOU CORRECT
MY WORDING
AND THEN TELL ME A LITTLE BIT
ABOUT WHAT THAT IS?

WELL, I'M
A PSYCHOACOUSTICIAN.

A PSYCHOACOUSTICIAN
IS SOMEBODY
WHO DESIGNS, CONDUCTS,
AND ANALYZES TESTS
TO STUDY THE PSYCHOLOGICAL
EFFECTS OF NOISE ON PEOPLE.

OH, PSYCHOLOGICAL
EFFECTS.

NOW THAT'S--THAT'S
KIND OF INTERESTING.

AND, RICH,
HOW ABOUT YOU?

CAN YOU DESCRIBE FOR US

JUST WHAT EXACTLY IS
A SENIOR RESEARCH ENGINEER?

WELL, SHELLEY, THERE'S A LOT
OF NOISE RESEARCH
THAT GOES ON HERE
RELATING TO AIRCRAFT NOISE.

AND I WORK WITH RESEARCHERS
BOTH HERE
AND AT NASA GLENN IN OHIO
AND NASA AMES IN CALIFORNIA
TO COME UP WITH WAYS
TO REDUCE THE NOISE
THAT AIRCRAFT MAKE.

(Silcox)
THE WORD ACOUSTICS MEANS:

WHY DON'T WE BEGIN
WITH THE RESEARCH
THAT BRENDA'S DOING?

BRENDA, WHY DON'T YOU
INTRODUCE SHELLEY
TO YOUR FELLOW
SOUND RESEARCHER?

CERTAINLY. SHELLEY,
MEET FRED THE HEAD.

THIS IS FRED?

THIS IS FRED.

FRED AND HIS FRIEND
NORM, HERE,
ARE ESSENTIALLY
MY RESEARCH.

TESTING FOR NOISE STARTS
WITH DECIDING
WHAT ASPECT OF NOISE TO STUDY.

FOR INSTANCE, THE SOUND
IN A COMMUNITY NEAR AN AIRPORT,
OR THE NOISES INSIDE
AN ACTUAL AIRPLANE.

SEE, THAT'S WHERE NORM
COMES IN.

I TAKE HIM UP
IN THE AIR--
INSIDE THE AIRPLANES
SO HE CAN RECORD THE NOISES
IN THERE IN FLIGHT.

SEE, HE'S GOT A MICROPHONE
IN EACH EAR.

THEY'RE KIND OF HARD TO SEE
ON NORM.

THEY'RE EASIER TO SEE ON FRED.

LET ME SHOW YOU.

(Canright)
OKAY.

YOUCH!

HE'S ALL RIGHT; HE'S USED TO
THAT SORT OF TREATMENT.

SEE, HE'S GOT A MIC IN THERE.

IT'S HARD TO SEE.

LET ME TAKE HIS SKULL OFF.

(Canright)
OH, WOW.

SEE, HE HAS A MICROPHONE
IN EACH EAR.

ANYWAY, THESE LITTLE MICROPHONES

RECORD THE SOUND
THAT'S HEARD BY EACH EAR
JUST AS YOU WOULD HEAR IT
YOURSELF.

I TAKE THIS BINAURAL RECORDINGS
I MAKE WITH NORM
AND BRING THEM BACK TO THE LAB.

I CAN EDIT THEM ON THE COMPUTER
AND PLAY THEM BACK
TO THE PEOPLE WHO COME IN
TO ACT AS SUBJECTS IN MY TESTS.

FOR INSTANCE,
I CAN TAKE SOME OF THE TONES
MADE BY THE PROPELLERS
OF THE PLANE AND REDUCE THEM.

AND PEOPLE CAN TELL ME IF
THEY PREFER THE REDUCED VERSIONS
AND HOW MUCH THEY PREFER THEM
SO THAT WE CAN PREDICT
THEIR REACTIONS
TO FUTURE NOISES.

OH, HOW INTERESTING.

SHELLEY,
IF YOU'D LIKE,
I CAN ARRANGE TO SHOW YOU
NASA'S 757 RESEARCH AIRCRAFT.

AND I CAN SHOW YOU THE PHYSICS
INVOLVED IN PRODUCING THE SOUND
AND HOW ONE GOES ABOUT
CONTROLLING THE SOUND.

OH, MAN,
THAT WOULD BE SO COOL.

I KNOW
I'D BE INTERESTED.

I'M SURE THE VIEWERS
WOULD BE INTERESTED
IN SEEING A REAL LIVE
NASA JUMBO JET RESEARCH PLANE.

[airplane thrumming]

SHELLEY,
THIS IS THE NASA 757
IN WHICH WE CONDUCT
VARIOUS TYPES OF RESEARCH.

NASA HAS A 10-YEAR GOAL
TO REDUCE NOISE IMPACT
FROM AIRCRAFT
SO THAT COMMUNITIES
HEAR 1/2 THE NOISE
THAT THEY HEARD IN 1997.

THE AMOUNT OF NOISE REDUCTION
IS SIMILAR TO THE DIFFERENCE
BETWEEN HEAVY TRAFFIC NOISE
AND LIGHT TRAFFIC NOISE.

THE NOISE IMPACT
REDUCTION EFFORT
IS LEAD
BY NASA LANGLEY RESEARCH CENTER
AND IS CONDUCTED
IN CLOSE PARTNERSHIP
WITH NASA GLENN RESEARCH CENTER
IN OHIO
AND NASA AMES RESEARCH CENTER
IN CALIFORNIA,
ALONG WITH HELP FROM ACADEMIA,
INDUSTRY, AND THE F.A.A.

WOW, THIS AIRCRAFT
IS HUGE.

WHERE DO YOU EVEN
BEGIN TO START
TO FIND
THE MANY SOURCES OF NOISE
THAT MUST COME
FROM THIS AIRCRAFT?

(Silcox)
IN SOME MODERN AIRCRAFT,
LIKE THIS 757,
A LOT OF NOISE IS GENERATED
FROM THE AIR TURBULENCE
CREATED BY THE WING FLAPS,
SLATS,
AND LANDING GEAR
SLICING THROUGH THE AIR.

TO CONTROL THIS TYPE OF NOISE,
WE USE COMPUTERS
TO CREATE DETAILED MODELS
OF THE AIRFLOW
OVER THESE SURFACES
AND LOOK FOR WAYS
TO SMOOTH OUT THE FLOW
AND REDUCE THE TURBULENCE.

SHELLEY, OF COURSE,
MOST OF THE NOISE
IS PRODUCED
BY THE JET ENGINE.

MODERN JET ENGINES
HAVE THESE LARGE FANS
THAT MOVE LARGE VOLUMES OF AIR
THROUGH THE ENGINES.

HOWEVER, THE FAN ITSELF PRODUCES
WHAT WE CALL FAN TONES.

THIS TYPE OF NOISE IS REDUCED
BY TREATING THE INLET
AND EXHAUST DUCT
WITH SPECIAL ACOUSTIC LINERS,
SORT OF LIKE TILES
FOR OFFICE CEILINGS.

AND, SHELLEY, THE BIGGEST
NOISE PROBLEM WE HAVE
IS THAT
OF JET EXHAUST NOISE.

WOW.

AND WORKING WITH US
IN JET EXHAUST NOISE
IS MARTHA BROWN.

HI, MARTHA.

HI, RICH.

YEAH, WELL,
HI, MARTHA.

HI, SHELLEY.

MARTHA, SHELLEY
HAS A PARTICULAR PROBLEM
IN NOISE ABATEMENT.

I WAS WONDERING IF YOU COULD
EXPLAIN TO MARTHA WHAT IT IS.

YEAH, THANKS, RICH.

MY PROBLEM IS THAT
I'M TRYING TO GET
SOME POINTERS
ON HOW TO REDUCE NOISE
FOR MY FRIEND, VAN,
AND HIS BAND, THE NOODLES.

THEY REHEARSE IN A GARAGE.

AND IT SEEMS
THAT THEIR REHEARSALS
ARE DISTURBING THE NEIGHBOR
AS HE'S TRYING TO TAKE A NAP.

SO WE'RE TRYING TO FIGURE OUT,
HOW CAN WE REDUCE THE NOISE,
OR THE SOUND,
COMING OUT OF THE GARAGE?

DO YOU THINK
YOU COULD HELP?

I'LL BE GLAD TO HELP,
BUT FIRST LET ME TELL YOU
A LITTLE BIT ABOUT MYSELF
AND WHAT I DO
A NASA LANGLEY.

OKAY.

I WORK AS AN ENGINEER
IN THE JET NOISE
LABORATORY.

I STUDY WAYS TO CHANGE THE AIR
COMING OUT OF A JET
WITH THE HOPE OF REDUCING NOISE
CREATED BY THIS AIR.

HIGH-SPEED AIR IS NEEDED
TO MOVE AN AIRPLANE FORWARD.

I WORK WITH A TEAM OF ENGINEERS
TO INVENT WAYS
TO CHANGE THE SPEED
OF THE AIR EXITING THE JET
BY JET MIXING.

SO JUST HOW DO YOU INCREASE
JET MIXING?

WELL, SHELLEY,
WE USE NON-ROUND SHAPES
LIKE
THIS RECTANGLE NOZZLE...

MM-HMM.

THIS ELLIPTICAL NOZZLE,
AND ALSO
THIS CORRUGATED NOZZLE.

OH, NOW, THIS REMINDS ME
OF A FLOWER WITH PETALS.

I SEE WHAT YOU MEAN,
BUT IN FACT,
THEY'RE CALLED LOBES.

LOBES?

YES.

AND ALSO WE MAY CHANGE
THE ROUND NOZZLE
AND HOW IT LOOKS
BY ADDING TABS AT THE ENDS
THAT YOU SEE HERE.

OH, NOW, THESE TABS
LOOK LIKE SHARK TEETH.

SO WHAT OTHER WAYS DO YOU HAVE
TO REDUCE NOISE?

WELL, SHELLEY,
WE USE MATERIALS
TO LINE THE INSIDE
OF THE NOZZLE.

YOU SEE,
THIS IS CALLED A LINER.

AND WHAT IT'S USED TO DO
IS TO ABSORB THE SOUND
BEFORE IT EXITS THE NOZZLE.

HMM.

LIKE A MUFFLER.

YES.

OKAY, LET'S GO BACK
TO VAN NOW.

WHAT ONE POINT MIGHT YOU MAKE
BACK TO VAN
THAT COULD HELP HIM
WITH HIS PROBLEM?

HMM...

I RECOMMEND
THAT HE BUY CEILING TILES
TO LINE THE CEILING
OF HIS GARAGE.

OH, OKAY.

MM-HMM.

AND, SHELLEY, HE CAN
INSTALL CARPET ON THE FLOOR
AND DRAPERIES ON THE WINDOWS
TO HELP REDUCE THE SOUND.

OH, RICH AND MARTHA,
THAT'S GREAT SOUND ADVICE,
AND I WILL SHARE THAT
BACK WITH VAN.

THANK YOU SO MUCH.

YOU'RE VERY WELCOME.

ALL RIGHT, AND TO THE REST
OF YOU, GANG,
I'M GONNA SEND YOU FIND VAN
AND SEE WHAT HE'S UP TO.

MEANWHILE,
I'M GONNA HEAD BACK
TO THE NASA CONNECT STUDIO
AND GET READY
FOR OUR SPECIAL GUEST.

AND IF YOU HAVEN'T THOUGHT
OF SOME QUESTIONS,
THINK ABOUT SOME,
BECAUSE IN A MOMENT,
YOU'LL BE ABLE TO CALL IN
WITH YOUR QUESTIONS.

I'LL SEE YOU BACK
AT THE STUDIO.