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Re: but does the pilot hear the sonic boom?



How so?

Is not the "bow" wave created at the bow * in front of the passenjares?
Therefore, Not quite:

http://www.madsci.org/posts/archives/feb98/886430559.Ph.r.html

Check out the links, also.

* leading edge of wave. All of the plane contributes to the acoustical
disturbance.

Can sound created ahead of the 'plane be heard, e.g. another plane's bow
wave? (Didn't find a ref. for this.)

bc

Kilmer, Skip wrote:

No. In a well-designed supersonic craft the only way you know you're =
going faster that (outside) sound is to watch the Mach meter.
skip

-----Original Message-----
=46rom: Larry Smith [mailto:larry.smith@SNOW.EDU]
Sent: Monday, December 01, 2003 10:50
To: PHYS-L@lists.nau.edu
Subject: but does the pilot hear the sonic boom?


At 3:46 PM -0600 11/24/03, Jorge Salazar wrote:


*********************************************************
Wednesday, November 26, 2003
SOUND SPEED
Sound waves move at about 340 meters per second -- about two-tenths =


of a


mile per second. A listener wonders if you can hear anything when y=


ou


travel faster than sound. The answer -- after this on Earth and Sky.
_________________________________________________________

DB: This is Earth and Sky. When we visited the National Air and Sp=


ace


Museum in Washington D.C., we got this question.

Caitlin Rush: My name's Caitlin Rush, and I'm from State College,
Pennsylvania , and I ask, "When you're traveling at the speed of sou=


nd or


faster can you hear anything?"

JB: Caitlin, the answer is yes. Imagine you're seated in a parked =


car.


You switch on the radio. The car's speakers begin to vibrate. The s=


peaker


cone presses against air molecules near the speaker, which push agai=


nst


neighboring air molecules. Much like firefighters passing a bucket,=


this


wave of pressure eventually reaches your ears. Your brain interpret=


s this


wave of pressure as sound.

DB: Now imagine you attach a pointy nose to your car and add enough
horsepower to break the sound barrier. As you cruise at more than 3=


40


meters per second -- that's more than two-tenths of a mile per secon=


d -- or


faster than the speed of sound -- you reach over and switch on the r=


adio.


Your car -- and you -- and all the air molecules around you -- are
traveling that fast. So the sound wave pushes away from the vibrati=


ng


speakers in exactly the same way it did in the parked car, and you c=


an hear


the sound.

JB: And that's good news for pilots and passengers of supersonic ai=


rcraft!


Thanks for your question, Caitlin. And with thanks to the National =


Science


Foundation, we're Block and Byrd for Earth and Sky.

http://www.earthsky.com/2003/es031126.html


*********************************************************