Secret Service agent Clint Hill quickly ran forward from the follow up car, just before the head shot at Z-313. He mounted the limousine then fell back, but managed to hold onto the rear bar (designed for agents standing on the rear running board). He recalled that if he let go and fell to the ground, he would have been run over by the follow-up car. Then followed a famous superhuman dash to get back on the limo. Analysing AntdavisonNZ’s panoramic Nix footage, his footfalls occur at the following Zapruder frames:
348 lands back on ground after first attempt to mount limo
349 left foot forward, right leg back
350 left leg planted, moving right leg forward
351 legs passing
352 legs together right slightly forward?
353 right leg forward
354 right foot planted, left leg back
355 right foot down, left leg back
356 legs together
357 left foot moving forward right foot leaving ground
358 left leg planted right leg back
359 left leg planted right leg moving forward
360 legs together
361 left leg back right leg moving forward (obscured)
362 right leg planted, left leg back
363 legs together
364 left leg back right leg obscured
365 left leg back right leg obscured
366 left leg back leaving ground right leg obscured
367 right leg on car left leg rising
368 right leg on car left leg rising
369 right leg on car left leg rising
370 right leg on car left leg dragging close to ground (hopping?)
371 right leg on car left leg dragging close to ground (hopping?)
374 right leg on car left leg dragging close to ground (hopping?)
375 right leg on car left leg dragging close to ground (hopping?)
376 right leg on car left leg dragging close to ground (hopping?)
377 right leg on car left foot on ground ground (hopping?)
378 right leg on car left leg raising
379 right leg on car left leg raising
380 both feet on car
I might have the left and right legs mixed up as it’s hard to tell which is which, but that doesn’t change the number of footfalls. He manages a footfall every four frames. Nix’s camera was running at 18.5 frames per second, or one frame every 0.054 seconds. This means Hill was completing a leg swing every 0.21 seconds.
In 1998 Harvard biology student Deborah Sternlight decided to look into what limits human running speed. Long story short, it’s a human limitation – we can only swing our legs so fast…
“To Sternlight’s amazement, whether people ran fast or slow, or whether they ran uphill or downhill, everyone had approximately the same swing time at top speed. Those running 14 miles an hour and those running 27 miles an hour both took between 0.37 and 0.40 second to swing one leg in front of the other.”
Harvard Gazette April 30, 1998
It would seem that Hill’s leg swing rate is physically impossible for a human. This leaves three possibilities. Either Nix’s film rate was about 9fps (I doubt it), or he wasn’t human (I’m assured he was), or frames have been cut from the Nix film in this sequence.
The latter hunch is supported by the work of many others over the years analysing the various films as well as witness testimony stating that the limousine slowed almost to a stop during the final head shot at Z313. Hill’s fancy footwork didn’t finish until at least Z362, suggesting that the limousine ambled for at least 2.5 seconds afterward the main head shot.
Whatever the reason for the frame deletions (perhaps just embarrassment that the limo had become a sitting duck?), it means that at least half of the Nix frames from this sequence are missing. If the Nix film is missing frames, then the concurrent Zapruder film could be too, as Costella has reasoned, as part of his claim that the film has been recreated.
This post was added a few days ago to the JFK Assassination Forum. Go there for a suggestion from Gayle Nix Jackson that a contributing reason could be that the film might not have been wound correctly. So I will look at the effect of over or underwinding on frame rates and what that might mean…