Back and to the right?

[Royell Storing]

I'm starting to think JFKs head just went limp after being shot in the back of the head and the forward movement of the limo caused JFKs limp head to fall back, just like his body goes back too shortly thereafter.

   The subtle head movement/tilt is caused by Jackie Pulling DOWN on JFK's arm/wrist. Then the EXPLOSION!. What we See as a result of the Head Shot is Unlike any Other Shot fired that day. Different Ammo, Different Weapon, Different Shooter.

[Royell Storing]

Yes, but the limousine was moving at a pretty steady speed of 8 mph, with only a little acceleration, a fraction of the acceleration that we see in JFK’s head, mild as it was. The movement (from Physics) inside a vehicle moving at a constant speed are the same as if the vehicle was stationary, relative to the vehicle.

    You need to look at the Z Film. JFK Limo Driver/SA Greer is Turned Around and looking BACK toward JFK. NO DRIVER turns and looks into the backseat of a moving car and maintains anything close to the speed they were previously traveling. SA Greer ain't Gumby.

[Joe Elliott]

    You need to look at the Z Film. JFK Limo Driver/SA Greer is Turned Around and looking BACK toward JFK. NO DRIVER turns and looks into the backseat of a moving car and maintains anything close to the speed they were previously traveling. SA Greer ain't Gumby.

You need to look at the Z Film. From my estimates, the limousine runs a steady 8 mph from z305 to z345.

From the study by William Hoffman, a physics graduate student, with much better skills at measuring than I have, and working from higher quality frames of the Zapruder film than I have access to, measured the speed of the limousine during z304 through z325. The limousine slightly accelerated from 7.89 mph to 8.22 mph. A very small acceleration. A much smaller acceleration than we see in JFK’s head, either in the forward or the backward movement. For all practical purposes, a steady 8 mph.

I don’t care if it shows the driver doing a handstand. If the Zapruder film shows the limousine moving a constant 8 inches forward with each Zapruder frame, then the film shows the limousine moving at 8 mph.

And in earlier head turns, yes, the driver did slow down the limousine but not the last one. With the limousine slowed to 8 mph, he could briefly look backwards without crashing, which is what he did.

[Joe Elliott]

Or is it? The limo was open to the air. This is not like being inside an airplane travelling at 500 miles an hour. JFKs head was open to the air.

Yes. The limousine was traveling at 8 mph. And the limousine was travelling into a head wind of 10 to 15 mph. So relative to the limousine, the wind was blowing at 18 to 23 mph.

On the other hand, the windshield would deflect a lot of this wind.

I don’t know what effect the wind would have on a limp head.

[Gerry Down]

Yes. The limousine was traveling at 8 mph. And the limousine was travelling into a head wind of 10 to 15 mph. So relative to the limousine, the wind was blowing at 18 to 23 mph.

On the other hand, the windshield would deflect a lot of this wind.

I don’t know what effect the wind would have on a limp head.

What i'm saying is, isn't the back seat pushing JFKs body forward at 8mph? And this would cause JFKs limp head to fall backwards. Just like if someone pushed you from the back without you expecting it. Your head would snap back?

[Royell Storing]

You need to look at the Z Film. From my estimates, the limousine runs a steady 8 mph from z305 to z345.

From the study by William Hoffman, a physics graduate student, with much better skills at measuring than I have, and working from higher quality frames of the Zapruder film than I have access to, measured the speed of the limousine during z304 through z325. The limousine slightly accelerated from 7.89 mph to 8.22 mph. A very small acceleration. A much smaller acceleration than we see in JFK’s head, either in the forward or the backward movement. For all practical purposes, a steady 8 mph.

I don’t care if it shows the driver doing a handstand. If the Zapruder film shows the limousine moving a constant 8 inches forward with each Zapruder frame, then the film shows the limousine moving at 8 mph.

And in earlier head turns, yes, the driver did slow down the limousine but not the last one. With the limousine slowed to 8 mph, he could briefly look backwards without crashing, which is what he did.

     Z304 - Z325 = Essentially 1 Second. Plus, the Limo is traveling DOWNHILL. COASTING DOWNHILL all by itself would increase the speed of an Extremely Heavy car like the JFK Limo. Get Real.

[Bill Chapman]

Or it is simply a neurological spasm, where all muscles are momentarily activated by a spurious signal. The signal starts at the top of the spinal column. It first reaches the neck muscles, which is why only the head is first affected. A little later it reaches the torso, which is why the torso did not start to move immediately, only the head. This explains which the acceleration is gradual and not all at once, as would happen with a bullet from behind.

I read where they had a hell of a time getting Kennedy out of the car; his feet were really jammed under the jump seat in front of him, apparently. Sounds like something related to a spasm of some sort. And someone said he had no shoes on when brought into the ER.

[Joe Elliott]

What i'm saying is, isn't the back seat pushing JFKs body forward at 8mph? And this would cause JFKs limp head to fall backwards. Just like if someone pushed you from the back without you expecting it. Your head would snap back?

No. If the limousine is moving at a steady speed, it acts as an ‘inertial frame of reference’. Everything that happens inside will happen the exact same way as if the limousine is still.

Inside a moving vehicle, moving at a constant speed, you can toss a ball back and forth normally. The seats won’t seem to be pushing against you. Acceleration will affect you, but not velocity.

If you slow down or speed up, that’s a different story. But at a constant speed there is no effect. Afterall we are moving on a rotating Earth at hundreds of mph. And hurdling around the sun at thousands of miles an hour. But we don’t notice it. The velocity does not vary much from second to second.

The limousine did speed up slightly, but way too small an amount to account for the movement of JFK’s head.

However, my understanding of Physics is limited to only the most basic principles of Classical Newtonian Physics, which I learned in high school. We could use William Hoffman to evaluate if the wind could have been a significant force in pushing JFK’s head backwards.