Posted on 08/08/2005 11:47:34 AM PDT by EnjoyingLife
"This view of the shock wave condensation collars backlit by the sun occurred during the launch of Atlantis on STS-106 and was captured on an engineering 35mm motion picture film. One frame was digitized to make this still image. Although the primary effect is created by the Orbiter forward fuselage, secondary effects can be seen on the SRB forward skirt, Orbiter vertical stabilizer and wing trailing edges (behind SSME's)"Source: NASA's Kennedy Space Center, Kennedy Media Gallery, Photo No.: KSC-00PP-1416, September 8, 2000, http://mediaarchive.ksc.nasa.gov/detail.cfm?mediaid=4720
Credits: Title and video details from http://Linkfilter.net/?id=91010 ("Stunning view of the Shuttle Atlantis condensation cloud") and http://ChamorroBible.org/gpw/gpw-20040817.htm (ChamorroBible.org: Prandtl-Glauert Condensation Clouds, 1st Collection)
In the title replace "Column of File" with "Column of Fire".
Cool picture.
Quick question.When the shuttle passes the speed of sound does it create a sonic boom?
Yes... it also creates a sonic boom when slowing down below the speed of sound during landing... actually it creates two booms when slowing, one from the fuselage and another from the wings.
I've never heard it from the ground, but it's probably too high by that time to hear. Maybe not much air at that altitude either.
"When the shuttle passes the speed of sound does it create a sonic boom?"
That's about the point of maximum aerodynamic pressure on the shuttle (max Q). Unfortunately, one time at max Q, there were two "sonic" booms (Challenger).
This is hilarious !
> When the shuttle passes the speed of sound does it create a sonic boom?
Almost anything traveling faster than the speed of sound
in the local medium generates shock waves continuously
while at or above that speed.
The boom is not caused by the transition from subsonic
to supersonic. You hear it as a boom (or more usually,
twin booms), because the shock wave is moving.
A vehicle going nearly straight up generates an
inverted funnel-shaped cone of shock waves. For the
STS stack, these are likely audible in some locales.
The orbiter definitely makes audible booms on approach
to landing, while still supersonic.
"A sonic boom is just the shock waves generated by objects which move faster than the speed of sound. Anything moving faster than the speed of sound is normally said to be moving supersonically. ... It can be shown that shock waves are always present when the object generating them is moving supersonically, i.e., when it is moving faster than the speed of sound. ... A conclusion that can be made immediately is that sonic boom will always be heard as long as the aircraft or other object is traveling supersonically and a human is close enough to hear it." (Emphasis in original.)Link: http://fluidmech.net/tutorials/sonic/sonicboom.htm
I was at KSC for the STS-106 launch that day. It was a stunning sight, as all the launches are.
Enjoy now. It is history.
now do that with the Viking Kittie...
ping
You're probably right about no one hearing the sonic shock waves during launch, if for no other reason then the rocket engines are so darn loud.
I also think the "speed of sound" and hence the "sound barrier" is a function of air mass density & it's elastic properties ( a function of both temperature & pressure) and therefore would change dramatically as the shuttle accelerates through the atmosphere. I seem to recall that "a" (speed of sound), goes up as the altitude increases and since you can't propagate sound in a vacuum, at some point it drops to zero. But there is no doubt that the speed of sound is broken, I always assumed it to happen when the controllers call the "max Q" point of the flight. Max Q being the altitude & air speed resulting in the maximum aerodynamic forces on the shuttle/booster. After which they throttle the main engines up to full power from something like the 2/3 used for takeoff.
Regards,
GtG
The good doctor was describing the shock wave(s) produced by an object (airplane, bullet, whatever) traveling HORIZONTALLY, above the earth's surface. The first shock wave attaches to the forward end of the moving object, a second attaches to the aft end. They propagate outward from the object at the speed of sound so that they assume a conical shape which eventually impacts the ground in a parabolic arc along the flight path. Visualize it like the three dimensional bow wave of a boat traveling through water which eventually hits the shore some distance behind the boat.
Now ask the good doctor, "What happens when the flight path is more or less vertical (ie: at right angles to the ground)"? I suspect that there is a very good chance that the shock waves do not in fact ever reach the ground but rather propagate at right angles to the flight path at that altitude. They do on landing because the shuttle is in more or less of a horizontal glide as it burns off the orbital speed.
Regards,
GtG
Those photos are too cool. Thanks for posting them!
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