The Most Important Error the FBI told the Warren Commission about the Rifle

[Robert Prudhomme]

And, of course, the simulations all show JFK being wide open, although looking at the first animation, JFK is just barely visible a z313, and becomes almost hidden at the 307 foot range, first claimed for the head shot by the FBI in WCD 298. We can certainly see that the two SS agents standing on the running board of the QM would be lined up with the trajectory of the bullet.

[Brad Milch]

I believe it's a sad state of affairs when an interested global public has to rely on 'cartoons' to explain how a homicide, carried out in public, filmed & witnessed by a multitude of people actually transpired. This is the gift initial investigators & MSM gave the public in their distorted version of events on Elm Street IMHO; this is their sordid legacy IMHO.

The public has wised up to this over the decades & some seek relief answers here at EF with diligent educators like Robert Prudhomme. That's why I pop up in his threads from time to time. The assassination of President Kennedy has always been, above all else, a shooting story. One or more humans shot & killed another human & wounded a couple more humans. Some sort of weaponry, ammo & shooting skills accomplished that evil deed 51 years ago. People have a right to study the case, examine the evidence & pursue alternate explanations of what occurred. Doing such does not make them 'kooks'.

BM

Edited February 8, 2015 by Brad Milch

[Robert Prudhomme]

I think I have worked out a diagram that will tell us if JFK was visible, at the z313 position and also at the position of the 307 foot trajectory first determined by the FBI, from the sill of the SE corner window of the 6th floor of the TSBD.

We know that the height of the shooter's rifle was 61.2 feet above street level. We also know that, from this point to the z313 position, Elm St. drops 11.76 feet. Therefore, it was necessary to add 11.76 plus 61.2 to make a total of 72.96 feet. Using the range of the head shot, as stated by the WC, of 265 feet as the hypotenuse, and the vertical height of 72.96 feet as the altitude, we were able to use Pythagorus's Theorum to determine the base of the triangle as 255 feet.

I drew this triangle on a piece of paper, and measured 11.76 feet up on the altitude to mark where the surface of Elm St. would be, and then drew a line down to the z313 position. This line, however, is not a true indication of the slope of Elm St., for when I entered all of these numbers into a grade calculator, it indicated an angle of 2.6°, not 3.13°. I believe what has happened is, as Brad says, Elm St. is not a steady 3.13° slope all the way from the corner to the Triple Underpass. As he stated, the true drop does not begin until almost to the bent tree on the south side of Elm St. In this case, we must make allowance for another .5° at z313, placing JFK lower than whatever our calculations show. For example, at 2.6°, there is a drop of .6 feet for every 12 feet forward, while at 3.13°, there is a drop of .7 feet for every 12 feet forward.

One simple way to allow for this is to simply calculate a position on our triangle's vertical side for a 3.13° angle, and draw it in; which I did. This gives us an unreasonable figure at the base of the TSBD, but gives us a realistic relationship between the trajectory of the bullet, the tops of the SS agents' heads and the base of JFK's head.

I have only a rough draft so far, and want to plot it all out on a much larger piece of paper but, so far, it is not looking good for the WC. It would be good to know the distance from JFK to the first standing SS agent. At the moment, I have simply marked off distances of 10, 20, 30 and 40 feet. I will keep everyone informed as I go.

P.S.

This is only the shot at z313 so far. If it looks this bad, the FBI's head shot of 307 feet, being roughly 45 feet further down Elm St., will be totally impossible.

Edited February 9, 2015 by Robert Prudhomme

[Jon G. Tidd]

Robert Prudhomme,

Excellent.

[Chris Davidson]

Robert,

http://www54.zippyshare.com/v/5AR0J73a/file.html

Robert West, the surveyor, had the ElmSt. slope average (3.13 degrees) begin at Station# 2+50 = elevation 429.7ft.

This is directly aligned with the snipers nest. Which was 15.5ft from the Houston/ElmSt corner.

chris

Edited February 10, 2015 by Chris Davidson

[Robert Prudhomme]

Hi Chris

There must be something going on here that is throwing the numbers off. I took all the numbers I had, the 265 foot trajectory to z313, the 61.2 foot vertical from the street to the rifle, and the 11.76 foot drop from the corner of Elm and Houston to z313, and calculated a right angle triangle with a base of 255 feet and a vertical of 72.96 feet. This gave me a right angle triangle with an acute angle of 16°. Either I have made a serious error somewhere, or the WCR was wrong in saying the trajectory at z313 was 18°.

But, there is another problem. I went to a handy site with a Rise/Run/Angle/Pitch/Slope calculator and entered all of the figures. One thing I wanted was a 3.13° sloping line inside my triangle, to represent Elm St. ascending to the TSBD from a point on the back of JFK's head. By placing the follow up car on this 3.13° sloping line, it will be possible to see if the standing SS agents are above the trajectory or not.

However, when I entered a run of 255 feet and an angle of 3.13° into the calculator, it told me there was a vertical difference of 14 feet between the bottom of the TSBD and z313. When I entered a run of 255 feet, and a rise of 11.76 feet, it told me the angle was only 2.6°.

The only place I can see where I could be using incorrect data is that the 265 foot trajectory is measured to the back of JFK's head, and the 11.76 foot drop is measured to the pavement beneath JFK at z313. I might have to recalculate, and use a drop that corresponds to JFK's head.

Just to go over it again, Chris, was the 11.76 drop measured all on the pavement, and the 61.2 feet measured from the sidewalk to the rifle? Did you mention something about also adding in the height of the curb, as well?

Edited February 10, 2015 by Robert Prudhomme

[Chris Davidson]

Robert,

http://www14.zippyshare.com/v/KQ8Quc1X/file.html

The 215.3ft would be the physical location on Elm St. to Z313, not from the base of the TSBD which forms the right triangle.

I wanted you to become familiar with the straight line street distance and vert/horiz ratio first.

The 52.78 inches "JFK head above ground" = 4.39ft.

Previously, I posted testimony from Robert Frasier I believe, who said they used an approx 2ft rise above the window sill as the rifle end height.

The equation is going to look something like this:

60.7ft sill + .5ft curb + 11.76ft ElmSt slope = 72.96ft

72.96ft - 4.39ft = 68.57ft

68.57ft + 2 ft = 70.57ft

The actual Z313 survey has this side at 70.25ft

A difference of 3.84 inches.

265.3ft hypotenuse, 70.57ft side and 255.74ft side = right triangle.

265.26ft """"""" 70.25ft """" and 255.8ft """ = Z313 survey.

Mr. EISENBERG - Could you show the lead in that diagram, Mr. Frazier?

Mr. FRAZIER - In Commission Exhibit 556, it shows a triangular diagram with the vertical line on the left-hand side illustrating the height of the building. The figures of a 60-foot building height plus--

Mr. EISENBERG - That is height of the muzzle above the ground?

Mr. FRAZIER - No--window sill--60-foot window sill height above the ground, with an assumed 2- foot height in addition to accommodate the height of the rifle above the possible. the possible height of the rifle above the window sill.

The horizontal line extends outward from the building to a small rectangular block, and then a sloping line illustrates a 5-foot slope from the 175-foot point to the 265-foot point.

chris

[Robert Prudhomme]

Okay, I think I am starting to get this now. I see how you made allowance for the height of the curb.

I entered the numbers from the z313 survey into the calculator, and it spat out an angle of 15.4°. Thinking to myself that we are having the bullet striking the pavement in this scenario, and, as you say, JFK's head was 4.39 feet above the pavement, I began to see a problem again. To correct for JFK's head being 4.39 feet above the pavement, would I simply subtract 4.39 from 70.25, and enter this into the calculator, along with 255.8 for the base?

I'm already seeing a problem with the FBI's numbers, as the FBI claimed the downhill angle of the shot to be 18°, and the calculator tells me their numbers work out to 15.4°. If I take away from the vertical side of the triangle by 4.39 feet, this angle decreases to 14.4°.

Edited February 10, 2015 by Robert Prudhomme

[Chris Davidson]

I'm not sure where you are getting the 18degree downhill angle of the shot from.

But, 18degrees - 2.6degrees = 15.4 degrees.

From CE884, entry for Z313, "Angle to horizon" rifle to JFK's head = 15.35 degrees included in the link at the right side

http://www76.zippyshare.com/v/ZasquaR6/file.html

chris

[Robert Prudhomme]

Hi Chris

Just made a post at the DPF where I explained my mistake. You're right, the WCR states the shot at z313 (265 feet from window) to be at an angle of 15.35°, while the FBI's WCD 298 has the second shot at 262 feet from the window, but at an angle of 18°. I confused the two sets of data.

I read your post again, more closely this time, and see now that you have already adjusted for the 4.39 foot elevation of JFK's head above the pavement in the manner I assumed would work. From what I recall, was the 4.39 foot measurement not to the top of JFK's head? As the autopsy placed the entrance wound in the head just to the right of the external occipital protuberance, could this account for the 3.84 inch vertical difference you pointed out?

[Ray Mitcham]

Bob, didn't software engineer, Tom Wilson, conclude that the head shot happened further down Elm Street. (I forget what distance he said). Could this help with your calculations?

[Robert Prudhomme]

Hi Ray

Yes, there seem to be rather a lot of indications, including the FBI report of 20/01/64 to the WC that was designated WCD 298, that the head shot occurred almost at the concrete steps.

Considering the difficulty of what I am attempting, that of seeing if the follow up car and its SS agents were blocking Oswald's view at the time of the head shot, I am going to work everything out at z313 first; simply because there is so much more data available for that location. If I am able to prove JFK was not visible at z313, it will almost be a foregone conclusion he would not be visible 45 feet further down Elm St., assuming the lateral alignment of the two cars does not change.

Edited February 10, 2015 by Robert Prudhomme

[Brad Milch]

Hi, Robert & Chris:

What you both are working on & presenting here is historically significant in this case. It hasn't been addressed, analyzed & published from Government investigation bodies & has been missed by researchers studying the case; namely, did a sniper's nest shooter have an unobstructed line of sight to JFK the ENTIRE length of the ambush. The public was simply told by the WC & its supporting MSM that a solo shooter shot JFK multiple times from the TSBD sniper's nest but failed to visually prove this in their photo re-enactments published in the WC Report & supporting volumes by omitting the SS guards & their transport car entirely. Robert & Chris are addressing what the initial investigators had swept under the rug.

If it helps, the last time I visited Dealey Plaza a couple years back, the 'flat spot' I described on Elm Street is still there. A visitor can feel it briefly while driving in the center lane. It's noticeable just past the reflecting pool & monument.

My friends & I used a thin tie-down nylon rope held between them to simulate the Queen Mary's windshield at Z-313 & our JFK 'actor' tried to see the bottom of the sniper's nest window above & below the rope. Unscientific? Yes. It was all we had to work with.

Also we had no correct height specs to work with, so we 'guestimated'. Our unscientific conclusion: with agents Landis & Ready out of the way (off the running board [simulated] and in the street, a shot to JFK's head from the sniper's nest at Z-313 would have probably struck Emory Roberts in the head or just missed him and cleared the windshield by a fraction or would have struck the windshield.

Dave Powers film is invaluable to visualizing the back of JFK's head & his back in relation to the Queen Mary's windshield. Powers had to stand up & film JFK in order to clear the windshield.

I concur with Robert that the sniper's nest shooter would have no shot at all around the pergola sidewalks steps. The more my friends & I traveled (on foot) down Elm Street towards the steps, the more the entire 6th floor sniper's nest window becomes blocked from view by a larger 'tailgater'. At Z-313 we didn't see an unobstructed shot possible either. These many years later, acknowledging that our amateur re-enactment was indeed amateur, I'm willing to concede that IF a sniper's nest shot occurred at Z-313 it was unbelievably tight in missing agents Landis, Ready, Roberts & the windshield of the Queen Mary, making such a shot from a mediocre shooter (Oswald) all the more remarkable when viewed in context of the entire ambush.

I left out the part we experienced where a DPD officer drove up & threated to take us to jail if we didn't get out of the street & leave. The thought of being arrested in Dallas & facing a possible jail transfer sent chills down our backs & we left before we could re-enact more. We had wanted to explore more.

BM

Edited February 10, 2015 by Brad Milch

[Robert Prudhomme]

This gets complicated but please bear with me.

Using the figures Chris obtained from the WC, I have been able to draw a right angle triangle depicting the shooter's trajectory from 2 feet above the sill of the 6th floor SE corner window to the back of JFK's head; 4.39 feet above the pavement. There is a little discrepancy here, as I believe the 4.39 foot measurement was to the top of JFK's head, and Humes reported the entrance wound on the lower back of JFK's head but, there will be plenty of time to address this.

My next step was to establish, on this diagram, where exactly Elm St. was in relation to the shooter and JFK's head. The simplest way to do this was to add the 4.39 feet to the vertical side of the triangle, or 4.39 + 70.25 = 74.64 feet. This number represents the vertical drop from the shooter's rifle, 2 feet above the window sill, to the pavement directly under JFK. I simply extended the vertical side of my triangle by 4.39 feet, and drew a lower base in parallel to the one going to JFK's head.

Knowing that Elm St. drops 11.76 feet, at a 3.13° angle, from the TSBD to the z313 position, I measured this amount upwards on my triangle from the new lower base line and marked it on the vertical side of the triangle. I then drew a sloping line from this point to the point I established on the pavement at z313, directly under JFK. This sloping line becomes Elm St., and JFK can be seen on this "street" with his head 4.39 feet above the "street". It is now a simple matter of marking points backward from the limo of 20, 30 and 40 feet on the "street" as varying positions for the follow up car, establishing heights for the SS agents and the follow up car, and placing them on the "street" to see if they project above the bullet trajectory or not.

So far, I've done everything with a pen, paper and ruler, and the results are a little rough. I have a friend who worked in a drafting office years ago, and he thinks he can produce something a little more polished for me. Once I get that, I'll see about getting it onto this thread.

Edited February 10, 2015 by Robert Prudhomme

[Jon G. Tidd]

Robert,

Your method works, assuming a constant downward slope for Elm Street as it moves west from the TSBD. I'm going to be real interested in any diagram you present.

FWIW, I've always believed re-enactments are worthless unless they take into account the follow-up car and its SS agents, as you're doing. Great work.