what mach 1 looks like - on the ground

not quite an airplane project but close




but i present Thrust SSC the first and to date ONLY car to break the sound barrier on the ground

now if you look at the front of the car you will notice lines extending either side - thats the front of the shockwave extending 150 feet either side

How about a couple vids to go with that?

reply to post by Harlequin



Now, going supersonic on land is a wild and cool notion but can't we here, of all places, drop the "breaking the sound barrier" thing? We all know there is no such thing as the sound barrier. Nothing really happens when going supersonic.

With my eyes glued to the Mach meter on the forward cabin bulkhead, I watched as our speed increased, anticipating some kind of bump that would signify we had gone supersonic. I was pleasantly disappointed.

source

You just go faster. That's it.

so , when you watch the video`s above - you can actually hear the front of the car going passed the shockwave and thus `breaking the sound barrier` -

en.wikipedia.org...

read up on shockwaves and breaking the sound barrier

it does exist - BUT when you are inside an aircraft or in the above case a car you cannot hear the boom youeself as your are ahead of it

Originally posted by Harlequin
so , when you watch the video`s above - you can actually hear the front of the car going passed the shockwave and thus `breaking the sound barrier` -

The front of the car (or aircraft) does not pass the shockwave. The leading edge of the shockwave forms and stays at the front of the vehicle. From your source:

In smooth flight, the shock wave starts at the nose of the aircraft and ends at the tail.

The sonic boom doesn't occur when the vehicle "breaks the sound barrier". It is a continuous phenomenon that occurs as the shockwave sweeps across the ground, following the motion of the vehicle. There is no barrier. Nothing is broken.



[edit on 3-10-2008 by Phage]

[edit on 3-10-2008 by Phage]

reply to post by Phage


Bah, stop being so pedantic. It was just a misnomer that stuck because, as I seem to recall reading some time ago, there was a notion that any aircraft approaching the speed of sound would break up from stresses.

There are "things that happen" in a fluid dynamics sense and fluid velocities within the turbines are kept subsonic by the inlet diffusers. I suppose I should crack open the fluid dynamic books again.

reply to post by EnlightenUp


I know. I know. I can't stop myself.

It's just one of those things that really gets to me.

Originally posted by Phage
Nothing really happens when going supersonic.

You just go faster. That's it.

You being serious about "nothing really happens"?

I am sure that Yager would chime in on this subject if he were here and tell you about what happens right before hitting mach 1.

And Scott Crossfield would tell you what happens going from mach 1 to mach 2.

Line em up and they will tell you the truth.

Cheers!!!!

[edit on 3-10-2008 by RFBurns]

Originally posted by RFBurns
I am sure that Yager would chime in on this subject if he were here and tell you about what happens right before hitting mach 1.

Transonic buffeting and possible control reversal (indeed, there would have been loss of control on the original Bell "X-1" had they not incorporated all moving elevators).

Originally posted by RFBurns
And Scott Crossfield would tell you what happens going from mach 1 to mach 2.

Nothing.

Exactly. A smooth ride and a glass o whisky for the road..er air.

Cheers!!!!

Originally posted by kilcoo316

Transonic buffeting and possible control reversal (indeed, there would have been loss of control on the original Bell "X-1" had they not incorporated all moving elevators).

Originally posted by RFBurns
And Scott Crossfield would tell you what happens going from mach 1 to mach 2.

Nothing.

OK. But transonic buffet has been, for all intents and purposes, eliminated in supersonic aircraft though aerodynamic design.

Modern aircraft can transition through the "barrier" without it even being noticeable.

Source

"Control reversal", more a loss of control of authority than an actual reversal of response is also a thing of the past.

There is no barrier. Nothing is broken.


[edit on 3-10-2008 by Phage]

Ok I have stayed out of this thread but I think you missed the point Phage. Just because modern tech and understanding of aerodynamics have reduced compressibility doesn't mean it doesn't exist. Robin Olds would tell you different in a P-38 with its thick wing. Is compressibility sound "no" but it is one of the phenomena associated with it. Also producing lift in supersonic is a different game so then understanding there challenged the types of designs that are useable. If you don't like the name of the barrier thats fine but I question why you think that shock-waves no longer effect high performance planes. they are still there and if not respected we could still lose aircraft due to shaking themselves apart.

Also the title of this thread is a clue in a way. The effects on the ground are the result of what? the shock-waves for sure and though its not the barrier defined as a stationary object that can be passed through and out of its almost the idea of the pushing against it and moving it around you. To the point where it once was is moved I guess.

pfft I sorta ranted long enough to say I disagree that the barrier has lose relevance or meaning.

[edit on 3-10-2008 by Canada_EH]

Originally posted by Phage
There is no barrier. Nothing is broken.

Apart from the bound vortex that creates subsonic lift.

Originally posted by RFBurns
Exactly. A smooth ride and a glass o whisky for the road..er air.

Cheers!!!!

Well, Scott Crossfield would tell one nothing, since unfortunately he died 2 years ago in his plane.