+

Cookies on the Business Insider India website

Business Insider India has updated its Privacy and Cookie policy. We use cookies to ensure that we give you the better experience on our website. If you continue without changing your settings, we\'ll assume that you are happy to receive all cookies on the Business Insider India website. However, you can change your cookie setting at any time by clicking on our Cookie Policy at any time. You can also see our Privacy Policy.

Close
HomeQuizzoneWhatsappShare Flash Reads
 

Here's what happens during a sonic boom

Jun 5, 2023, 22:41 IST
Business Insider
Two US Air Force F-16 Fighting Falcons.US Air Force photo by Tech. Sgt. Matthew Lotz
  • A sonic boom is the loud noise that results when something breaks the sound barrier.
  • You break the barrier by traveling faster than the speed of sound, which is 768 mph at sea level.
Advertisement

An F-16 scrambled to intercept a nonresponsive plane on Sunday, and the fighter jet caused a sonic boom heard in the DC area.

A sonic boom is a loud noise that people on the ground can hear when an aircraft, for example, breaks the sound barrier by traveling faster than the speed of sound.

Supersonic flight is banned over land in the US without special government authorization because of the inconvenient noises and tremors it can produce.

Here's what happens when a plane breaks the sound barrier:

When a plane goes fast enough, it compresses the air it's flying through so much that it can change its density, creating shock waves in the shape of a cone.

These shock waves act just like the wake behind a boat, which happens because it disrupts the water by moving faster than the water waves were moving.

Advertisement

Air pressure right at the tip of the cone in front of the plane is normal, while the pressure inside the cone is high because of the plane passing so quickly through it and pushing the atoms of air together.

Since the plane concentrates the sound wave energy into one place, you hear it all at once — producing a "boom" noise instead of the typical sound of a jet flying by.

This T-38C, a supersonic US Air Force training jet.US Air Force

NASA developed a way to see supersonic shock waves, and the images are gorgeous

NASA and the US Air Force have been trying to visualize this effect for years so they can build better supersonic aircraft and enable them to go faster than the speed of sound.

Until recently, these kinds of tests were contained to wind tunnels on the ground.

There, researchers used the Schlieren technique, invented by German physicist August Toepler in 1864, to understand more about how air travels around supersonic aircraft.

Advertisement

Schlieren imaging is a way to see the differences in air density, using a particular setup of lenses and cameras.

Decades later, NASA researchers have adapted this method to visualize supersonic aircraft in flight.

Bringing the Schlieren method into the air has been challenging because the aircraft carrying the imaging equipment has to fly right above the plane it's recording, and travel just as fast — which, during supersonic imaging, is faster than the speed of sound.

The T-38C, a supersonic US Air Force training jet that NASA imaged, traveled at a top speed of Mach 1.09 during the tests. (Mach 1 is the speed of sound, which is about 768 mph at sea level.)

But the tricky maneuvering was worth it for these gorgeous images, showing the shock wave of the T-38 flying over the Mojave Desert:

Advertisement
This schlieren image dramatically displays the shock wave of a supersonic jet flying over the Mojave Desert. Researchers used NASA-developed image processing software to remove the desert background, then combined and averaged multiple frames to produce a clear picture of the shock waves.NASA

Here's another Schlieren image visualizing the supersonic flow of the T-38 jet in flight:

NASA is using a 21st century version of schlieren imagery, invented by a German physicist in 1864, to visualize supersonic flow phenomena with full-scale aircraft in flight.NASA

Understanding more about how supersonic aircraft affect the air around them could help develop ways to make planes quiet enough for commercial travel, opening the door to make the trip from New York to London a whole lot faster.

You are subscribed to notifications!
Looks like you've blocked notifications!
Next Article