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NASA captures amazing images of sound waves from supersonic jets

Nick Whigham, March 18, 2019 6:30PM news.com.au

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Two T-38 aircraft flying in formation at supersonic speeds producing shockwaves that are heard on the ground as a sonic boom. NASA has been able to “see” the shockwaves moving around the planes. Picture: AFP/NASA media_cameraTwo T-38 aircraft flying in formation at supersonic speeds producing shockwaves that are heard on the ground as a sonic boom. NASA has been able to “see” the shockwaves moving around the planes. Picture: AFP/NASA

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NASA has photographed sound waves from two supersonic* jets in flight.

The incredible images will help NASA better understand how supersonic waves work and further its quest* to design supersonic aircraft that quietly rumble rather than boom when they crash through the sound barrier*.

Supersonic flights could then be allowed over land.

It took NASA 10 years to get these groundbreaking photos.

The T-38 aircraft are flying faster than the speed of sound. As they move through the air faster than sound they produce shockwaves, which these images have captured. Picture: AFP/NASA media_cameraThe T-38 aircraft are flying faster than the speed of sound. As they move through the air faster than sound they produce shockwaves, which these images have captured. Picture: AFP/NASA

The scientists could hardly believe their eyes when the images were developed.

“We never dreamt that it would be this clear, this beautiful,” said JT Heineck of NASA’s Ames Research Center in a statement.

The pictures show two T-38 supersonic jets tearing through the atmosphere and creating sonic* shockwaves*.

Shockwaves are created by aircraft flying faster than the speed of sound. The shockwaves produced by aircraft merge* together as they travel through the atmosphere and are responsible for what is heard on the ground as a loud sonic boom.

NASA wants to design a quiet supersonic aircraft and these results will inform its plans to build its experimental X-59 QueSST quiet supersonic jet dubbed “the son of Concorde” which it began work on late last year.

A drawing of what the Lockheed X-59 QueSST could look like. Picture: NASA media_cameraA drawing of what the Lockheed X-59 QueSST could look like. Picture: NASA

The photos were taken by advanced camera equipment on a plane that flew about 600m from the two T-38 jets as they flew less than 10m apart from each other.

“I am ecstatic about how these images turned out,” said Mr Heineck.

Supersonic shockwaves created by a single T-38. Shockwaves created by a single aircraft look like straight lines emanating like a cone off the tip of the aircraft. The shockwaves seen in the images where two planes are close together are shaped differently. Picture: AFP/NASA media_cameraSupersonic shockwaves created by a single T-38. Shockwaves created by a single aircraft look like straight lines emanating like a cone off the tip of the aircraft. The shockwaves seen in the images where two planes are close together are shaped differently. Picture: AFP/NASA

For the first time, the interaction of the shocks can be seen in flight, NASA said.

“What’s interesting is, if you look at the rear T-38, you see these shocks kind of interact in a curve,” said Neal Smith, a research engineer with AerospaceComputing Inc. at NASA’s Ames fluid mechanics laboratory.

“This is because the trailing T-38 is flying in the wake of the leading aircraft, so the shocks are going to be shaped differently. This data* is really going to help us advance our understanding of how these shocks interact.”

SOUND
Sound is a wave that moves, or vibrates, through air, water or other material. We hear sound when the waves or vibrations reach our ear.

Low frequency waves (spread out, slow waves) we hear as low sounds. High frequency waves (close together, fast waves) we hear as high sounds.

Sound is a wave that moves, or vibrates. We hear a sound when the wave reaches our ears. media_cameraSound is a wave that moves, or vibrates. We hear a sound when the wave reaches our ears.

CONCORDE
Concorde was a type of supersonic passenger jet that flew between 1976 and 2003.

They flew at Mach 2.04, which means just more than twice the speed of sound.

Flight time between New York, US and London, UK, was about three hours.

They were expensive to develop and run and very noisy because of the sonic boom.

Only 14 jets ever flew and they were never profitable.

Concorde aircraft, which were the world’s first supersonic passenger aeroplanes. media_cameraConcorde aircraft, which were the world’s first supersonic passenger aeroplanes.

GLOSSARY

  • supersonic: faster than the speed of sound
  • quest: journey of discovery
  • sound barrier: or sonic barrier; sudden increase in drag when an aeroplane is about to go as fast as sound
  • sonic: relating to sound and sound waves
  • shockwaves: sudden change of pressure caused when something moves through an area faster than sound
  • data: information

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QUICK QUIZ

  1. Do supersonic jets go slower or faster than the speed of sound?
  2. How long did it take for NASA to get these images?
  3. What sort of jets are in the pictures?
  4. What is the name of the experimental supersonic jet?
  5. What were some of the reasons Concorde wasn’t a success?

LISTEN TO THIS STORY

CLASSROOM ACTIVITIES
1. Supersonic Travel
Supersonic jets that travel faster than the speed of sound could have a huge effect on the travel industry and the way people work and live.

Work with the person beside you. Divide a page up into a table of six sections. Your heading is:

SUPERSONIC TRAVEL — HOW WILL IT AFFECT THE FOLLOWING GROUPS

Label each of the six sections as:

businessmen and businesswomen

international conferences and events

holidaying families

international students

airlines and other transport companies

holiday industry, including resorts and hotels

Brainstorm as many ideas as you can and fill in your table as you go.

Time: allow 25 minutes to complete this activity
Curriculum Links: English, Personal and Social, Critical and Creative Thinking

2. Extension
Look carefully at the NASA images of the supersonic jets flying close to each other. What observations can you make about the patterns? Does anything else strike you?

How does the image of one jet differ to the ones with the two jets?

Time: allow 10 minutes to complete this activity
Curriculum Links: English, Critical and Creative Thinking

VCOP ACTIVITY
With a partner see if you can you identify all the doing words/verbs in this text. Highlight them in yellow and then make a list of them all down your page. Now see if you and your partner can come up with a synonym for the chosen verb. Make sure it still makes sense in the context it was taken from.

Try to replace some of the original verbs with your synonyms and discuss if any are better and why.

HAVE YOUR SAY: Would you fly on a supersonic jet?
No one-word answers. Use full sentences to explain your thinking. Comments will not show until approved by editors.

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