Sonic boom?

Question

When a jet fighter travel at supersonic speed across the sky, it will leave a sonic boom. This is especially so if it is flying low in the sky.

However, if the fighter aircraft were to fly very high up in the sky, nearly reaching the stratosphere where the air is very thin, will it still create the sonic boom?

Will a thin atmosphere reduce the sonic boom?

Answer 1

There is a lot of confusion among the general public about supersonic flight, caused in fair measure by articles such as the one Nova put out. Typical of the media, they got it wrong. And the speed of sound REDUCES as you increase altitude, not the other way around. That speed is 763 mph at sea level on the defined standard day. At altitudes around 40,000 feet, that speed is 663mph. The article in Wiki comes closest to accuracy and they rely on the tests performed by NASA, not some reporter's interpretation of data he doesn't understand to begin with. In point of fact, the boom is reduced for those on the ground by lower altitudes. The stratosphere is a defined piece of sky that starts around 32,000 feet and extends upward to about 158,000 feet. That's a lot of sky. Above 40,000 feet the boom is actually greater than at altitudes below that. Military aircraft flying in the 70,000 foot and slightly above that still produce a pronounced boom, and very few aircraft fly that high or much higher. Certainly no civilian craft do. There has been a lot of study on the subject and there is still a lot unknown. It is an interesting study if you have the time, though.

Answer 2

Most definately I can remember the days were a sonic boom was legal. I heard about thyis after asking the same question at Wright Patterson Airforce Museum you may here the boom but by the time you do and look for the plane it will be far out of site. Look at the SR-71 it leaks feul all over the place on take off re-fuels in the air and heads towards space! They were going to retire it because of spy Sattlites but they found a new use for it studying the O-zone as far as I know they still use it for that purpose and their is back in legislation to lift the ban on the sonic boom for several reasons #1 it hasn't had the effect on the enviroment as they thought. Maybe in the near future we will hear these booms on a regular basis again they are awesome. The Blue Angels were here for a airshow and the make a wish fondation got there very own special show since alot of the kids were deaf the piolot made a sneak pass causing a very low level sonic boom which I was in a farm field taking pics and he scared me and knocked me on my hind end. It was worth it though seeing the flame coming out the hind end those guys are awesome. In my book any military pilot is awesome no matter what aircraft they fly it takes a special talent. Also there are movies out there about when they tried to reach mach-1 or the speed of sound which was done by Chuck Yeager with a couple broken ribs and help getting into the craft. The night before he had a horse throw him! A lot of men lost their lives trying to reach the speed of sound and break that sound barrier. Basically the planes couldn't structally hold up

Answer 3

Any time an aircraft or spacecraft breaks the sound "barrier", it creates a shock wave, and the resulting "Sonic Boom".
It is not the density of the air, but the distance from the ground that matters. The shock wave and "boom" is still created, but, due to the extreme altitude, the intensity of the sound is far less than at lower altitude.
Just as the sound of an explosion on the ground is much louder the closer you are to it, so it is with a "sonic boom" the closer a supersonic aircraft is to the ground.

Answer 4

I'm not exactly sure if my answer is completely true, but based on my knowledge of sound, I will do my best. Since the air is thinner in the stratosphere, it stands to reason that the sonic boom would be decreased because the sonic boom is, of course, a sound. And all that a sound really is is air particles pushing together and traveling in waves. So, if there is less air to push together, it would make sense that a sound would be quieter.

Answer 5

Sonic boom is a step change in pressure in the air. If the aircraft is travelling at transonic speeds in air, then a shock wave will be created. At high altitudes, the chances of the wave reaching the ground is much smaller.

Answer 6

The boom will still occur, however it may not reach the ground, for the simple reason that as a sound wave descends towards the ground it tends to curve upwards and a boom created at high altitudes may actually miss the ground completely.

Answer 7

No, when the space shuttle comes back into the atmosphere even at ultra high altitudes it creates a sonic boom

Answer 8

The thinner the air, the more speed needed to reach supersonic and create a sonic boom.

Also, of course, the higher you are the less chance it will be heard on the ground.

Answer 9

When near to the edge of the stratosphere a sonic boom may occur but it would require a higher speed and it may not be heard. :] Wow! Air cadets did come in handy.

Answer 10

When an aircraft breaks the sound bearer it leaves a sonic boom.