Oswald took 10.2 seconds to fire all three shots.

[Tom Graves]

I envision him staying concealed until all of the SS agents have gotten so close to the building that they would have to be looking almost straight up to see him. Then quickly raising the rifle and preparing to shoot from behind them. A well-designed ambush.

Devil's Advocate: There were Secret Service agents in LBJ's car.

[Charles Collins]

Devil's Advocate: There were Secret Service agents in LBJ's car.

And SS agents were behind LBJ's car in the follow-up car. Yes, they too would be very close to the building. Specifically by the time the limo emerges from behind the tree (where I believe he would have planned to begin shooting).

[Brian Roselle]

The shock wave is due to the rapid compression of air by the bullet and spreads out from the nose of the bullet in a cone shape at the speed of sound as the bullet passes through the air.  The angle of the cone is called the Mach angle where the sine of the Mach angle is equal to the speed of sound divided by the bullet speed (or 1/mach no.):


In the case of the bullet fired by the M/C rifle (muzzle speed Mach 2 around 2200 feet/sec), the Mach Angle would be 30 degrees (sin(30)=1/M=1/2).  The energy in the wave is continuous as it is caused by the bullet plowing through air whereas the muzzle blast is a one-time release of energy caused by the compressed gas from the ignited gunpowder exploding out of the muzzle.

So, it appears to me that Wiegman and Kilduff and the Cabells were not within the cone and could not have heard the crack of the shock wave.  Only people west of the SN and relatively close to the bullet path could have heard it.

That looks like a very good description related to shock waves and expanding as a cone. I agree with your conclusion that those individuals around the intersection would not have encountered the shock waves.

What I think is interesting and implied by what you describe is that for any three shots (time wise) from the depository, Greer and Kellerman, even though they would have been basically right in line with the bullet trajectories, probably would not have heard shock waves either. If the bullets or fragments went subsonic just before reaching them, it seems those two would have been engulfed inside a truncated expanding shock cone, and as such never heard the shock wave. Just a consequence of the geometry.

[James Hackerott]

Many years ago I created a 3D stabilized version of the Z-film (need Red/Blue glasses for 3D effect) and I used the stabilized data to study the camera shake.

If Zapruder responded to any loud noises during shooting the Z film, then telltale jiggles would show up as involuntary camera shake. If you take any stock in involuntary "jiggling" in response to loud sounds (which is definitely a thing), this chart might interest you.

http://www.kohlbstudio.com/Images/Zshake_yd-d.png

A reflexive response to a loud noise is an up and down motion (y axis). I filtered out the X and focused on the Y because this jiggle motion is significant versus "panning", which is not associated with a gunshot jiggle. All the other jiggle analyses seemed to ignore this aspect.

Look at the "signature" reflexive response to z313. That is your control.

There appear to be a few possible candidate spikes that might have been the 1st shot. However, there were a lot of frames spliced out of the beginning of the Z-film and Zapruder can't recall ever taking his finger off the trigger. The 1st shot might be in that footage, which got spliced out. BTW, where is the original film? Zapruder only got a copy back.

Note that there's a telltale jiggle that peaks at z230, which suggests that Zapruder was responding to a sound at z225. The sound appeared to reach Zapruder 1/6th of a second after the bullet struck JFK at z222, behind the Stemmons sign.

Note the splices at z158 & z213.

Note the massive edit at z333 just when we would expect to see a hole in the back of JFK's head.

Love it! Viewed with my Red/Cyan clip-on.

[Andrew Mason]

That looks like a very good description related to shock waves and expanding as a cone. I agree with your conclusion that those individuals around the intersection would not have encountered the shock waves.

What I think is interesting and implied by what you describe is that for any three shots (time wise) from the depository, Greer and Kellerman, even though they would have been basically right in line with the bullet trajectories, probably would not have heard shock waves either. If the bullets or fragments went subsonic just before reaching them, it seems those two would have been engulfed inside a truncated expanding shock cone, and as such never heard the shock wave. Just a consequence of the geometry.

I agree.  The supersonic compression of air stops being generated when the bullet stops.  If a person is ahead of the bullet when it stops and ahead of a line from the bullet in the direction of the shock wave trajectory, that person cannot sense the shock wave:

[Royell Storing]

 So how does Kilduff while sitting inside a Hard Top/Closed Car feel a "muzzle blast" that originates from the 6th Floor? He doesn't. Now, if a gun was fired from inside that same car, you gotta story.

[Marjan Rynkiewicz]

That looks like a very good description related to shock waves and expanding as a cone. I agree with your conclusion that those individuals around the intersection would not have encountered the shock waves.

What I think is interesting and implied by what you describe is that for any three shots (time wise) from the depository, Greer and Kellerman, even though they would have been basically right in line with the bullet trajectories, probably would not have heard shock waves either. If the bullets or fragments went subsonic just before reaching them, it seems those two would have been engulfed inside a truncated expanding shock cone, and as such never heard the shock wave. Just a consequence of the geometry.

Brian u are usually good at logic/science, apart from your decision to engage with some of the morons on this forum.
But your comment means that u/me/we/us cant hear an/any/all explosions.

In other words, there is no such thing as a shock wave.
What we have is sound. And if the leading edge of the sound is powerfull then we might call it a shock wave.
So, at what distance duzz a shockwave stop being a shockwave.
Answer, there is no answer, koz there is no such thing as a shockwave, its just sound.
Trump got a bloody ear from a shockwave, a  nearmiss, lucky.