It's just that a frame like Z162 is "just about in front of me".
Chism would be watching the car as it neared him. The Willis photo is about two seconds later and the Chisms appear pretty close to the car, so certainly some looking up towards the car before that.
However, Chism seems to recount just two shots:
"And just as he got just about in front of me, he turned and waved
at the crowd on this side of the street, the right side; at this point
I heard what sounded like one shot, and I saw him, "The President,"
sit back in his seat and lean his head to his left side. At this point,
I saw Mrs. Kennedy stand up and pull his head over in her lap,
and then lay down over him as if to shield him."
In that case, the "first" shot is the one before the head shot. He's describing as the "first shot" the SBT shot in the Z220s. Another thing, too, Chism wasn't sure about the number of shots, allowing for up to three. But he could only really recount what happened during two of those.
If the first of the three shots was the one he lost track of, it's possible he heard it while the car was further up Elm.
His wife, Marvin Faye, is also "first shot" before the head shot:
"As the President was coming through, I heard this first shot, and the
President fell to his left. The President's wife immediately stood over
him, and she pulled him up, and lay him down in the seat, and she
stood up over him in the car. The President was standing and waving
and smiling at the people when the shot happened.
And then there was a second shot that I heard, after the President's
wife had pulled him down in the seat."
Likewise, Jean Newman. So basically, their statements could be a way to situate the moment of the second shot, rather than the first. The general consensus is that three shots were fired, with the head shot being the last.
The eyewitness accounts are interesting but often not reliable. I look at the film for subjectivity (yes, film and digital recording can be manipulated, but this one seems accurate).
The turning of the heads of the Connallys and Mrs. Kennedy just as Rosemary Willis begins to slow to stop: that's first shot territory. The simultaneous reactions of both men in the Z220s: that's second shot territory. The head shot: obvious, but the head initially goes forward first, so consistent with SN.
Both Chism and Newman could not have been more explicit in declaring they only heard two shots. It does not require any explanation or interpretation if you just read what they stated. Jean Newman states the first shot occurred after the car was past her not before. The first shot took place when the limo was between where Jean Newman and the Chisms were standing not before it got to them.
Jean Newman:
My name is Jean Newman. I live with my parents, my father's name is G. O. Kimbriel. I work at the Rheam Manufacturing Company.
I was standing right on this side of the Stemmons Freeway sign, about half-way between the sign and the edge of the building on the corner. I was by myself, there were other people around watching the motorcade. The motorcade had just passed me when I heard that I thought was a firecracker at first, and the President had just passed me, because after he had just passed, there was a loud report, it just scared me, and I noticed that the President jumped, he sort of ducked his head down and I thought at the time that it probably scared him, too, just like it did me, because he flinched, like he jumped. I saw him put his elbows like this, with his hands on his chest.
By this time, the motorcade never did stop, and the President fell to his left and his wife jumped up on her knees, I believe it was, in the back of the car on her knees, I couldn't say that for sure. And I realized then it had been a shot. I looked in the car and she was on her knees, and he wasn't even visible in the car. I looked around then, and everyone was running every which way, I don't know why I didn't run, I just stood there and backed up and looked around to see if I could see anything, but I saw no one whatever with anything that resembled a gun or anything of that kind.
I just heard two shots. John Chism:
When I saw the motorcade round the corner, the President was standing and waving to the crowd. And just as he got just about in front of me, he turned and waved at the crowd on this side of the street, the right side; at this point I heard what sounded like one shot, and I saw him, "The President," sit back in his seat and lean his head to his left side. At this point, I saw Mrs. Kennedy stand up and pull his head over in her lap, and then lay down over him as if to shield him.
And the two men in the front seat, I don't know who they were, looked back, and just about the time they looked back, the second shot was fired. At this point, I looked behind me, to see whether it was a fireworks display or something. And then I saw a lot of people funning for cover, behind the embankment there back up on the grass.
And at this point, I turned back around and saw the motorcade beginning to speed up, and everybody was laying down but the driver, of course. I didn't notice where it went. My wife and I began seeking cover, and we went to our car, and then we told the policeman about what we knew.
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This particular statement by John Chism exactly matches to what Kellerman testifies to in his WC testimony about turning after the first shot and before the second, the head shot.
"And the two men in the front seat, I don't know who they were, looked back, and just about the time they looked back, the second shot was fired"Kellerman Official Report
"We were still traveling at the normal rate of speed of from 12 to 15 miles per hour when
I heard a noise, similar to a firecracker, exploding in the area to the rear of the car, about 12:30 p.m....... I turned around to find out what happened when two additional shots rang out, and the President slumped into Mrs. Kennedy's lap and Governor Connally fell_to Mrs. Connally's lap."
WC testimony:
Mr. KELLERMAN. As we turned off Houston onto Elm and made the short little dip to the left going down grade, as I said, we were away from buildings, and were there was a sign on the side of the road which I don't recall what it was or what it said, but we no more than passed that and you are out in the open,
and there is a report like a firecracker, pop. And I turned my head to the right because whatever this noise was I was sure that it came from the right and perhaps into the rear, and as I turned my head to the right to view whatever it was or see whatever it was
Mr. SPECTER. Would you say the acceleration--
Mr. KELLERMAN. Between the second and third shot. Senator COOPER. Might I ask a question there?
Mr. SPECTER. Yes.
Senator COOPER. A few minutes ago you said in response to a question that when you spoke to the driver the car leaped forward from an acceleration immediately.
Did that acceleration occur before the second shot was fired?
Mr. KELLERMAN. Yes, sir. Just about the time that it came in.
Senator COOPER. About the time it came in?
Mr. KELLERMAN. Yes, sir.
Senator COOPER. Not before?
Mr. KELLERMAN. No.
