Subject: Re: Speed of JFK Limosine
Date: 02 Aug 1999 17:33:12 GMT
From: sfz@aol.com (Sfz)
Organization: AOL http://www.aol.com
Newsgroups: alt.assassination.jfk

I'm reposting just the smoothed speed figures, since the multicolumn
version was pretty messy.

I can now say that the speed of the car is almost certainly related to
Greer turning around to look in the back seat.  I've written before that
there are two turns by Greer:  F285:  Driver Greer appears to be looking
in the rear view mirror
   F291-5: driver takes a very quick glance to the rear
   F302-5: Driver twists to look into back of car
   F316: driver begins turning back to front, and will duck forward In the
smoothed data we can see very clearly that the car actually goes through
two deccelerations, both of essentially the same rate (of between 3.6 and
5 mph/sec) with each episode lasting about a quarter of a second.
Although Greer is in shadow, we can verify what direction he is looking by
comparing the outline of his head - an oblong outline means his head is
looking forward or backward, and a rounded, smaller outline means he is
looking towards the camara.

Thus I repeat: the car slowed down when Greer turned to look into the back
seat.  I slowed down because the act of twisting to look back caused his
right (accelerator) foot to lift.

I also note that Greer essentially stomped the accelerator at F338,
yielding an acceleration of about 11 mph/sec - not a bad zero-to-sixty
time for a big car.  The force on Jackie as she rose would have been
terrific, especially as she was facing rear and without warning or
support.  It is amazing to me that she didn't slide right out of the car -
and migh have had Greer not let up apparently because he saw Jackie and
perhaps Hill on the trunk.

Frame   smoothed
        speed
260
263     11.7
266     11.3
269     11.8
272     11.6
275     11.6
278     11.4
281     11.1
284     11.2
287     11.1
290     10.8
293     10.3
296     9.8
299     9.4
302     9.5
305     9.5
308     9.7
311     9.3
314     8.9
317     8.7
320     8.3
323     8.4
326     8.3
329     8.5
332     8.6
335     8.8
338     8.9
341     9.3
344     10.1
347     11.3
350     11.8
353     12.6
356     13.2
359     13.9
362     14.4
365     15.0
368     15.7
371     16.3
374     16.7
377     16.8
380     17.1

Note:  after F380 the car stops accelerating for a bit, apparently to let
Hill and Jackie get situated, and then it takes off again.

regards

Steve Zeigler