Fact: the official strike speed of Fl. 175[2nd plane] into WTC2 was 520 knots, which is 598 mph.
However the maximum speed of a Boeing 767-200 is stated as being 567 mph. at 35,000 ft [where the air is 1/4 of the density it is at 1000 ft.] :
Meaning that at anywhere near the altitude of 1000 ft. [ the approximate official F. 175 strike altitude on WTC2] , where the air is 4 times denser, an airspeed of anything like 598 mph would be physically impossible for a 767 jetliner.
As this Pilots For 9/11 Truth video demonstrates:
.... at that speed [598 mph] at that altitude,[1000 ft.], the plane would have simply broken apart pre-strike due to the larger than designed for forces exerted on it by the 4x denser [than at 35,000 ft.], air mass.
Therefor, any "official" 9/11 video that showed a frame to frame plane image speed of anything like 500+ mph must be fraudulent in some way, right ?
Exhibit A: Original "Live" Network Footage [as archived on line]
So what if a "big time" US network had an original "live"sequence in its official archives on line showing a frame to frame plane speed close to 550 mph?:
Here is the relevant [much shorter] part of the same Fox broadcast, specifically showing the 2nd alleged plane hit [WTC2], on Youtube:
Wouldn't that [ frame to frame plane speed of close to 550 mph] make this sequence er, "untrustworthy"?
[To put it mildly :- ) ]
Here is my evidence that the famous Fox5 live sequence showing Fl. 175's alleged collision with WTC2, as supposedly filmed by a helicopter, shows an impossible plane approach speed [of around 540 mph. ]
In order to calculate frame to frame speed of the plane, we would need to know 3 important facts:
1] Length of plane.
2] the number of frames the plane takes to travel its own length.
3] the number of frames per second of the camera.
Knowing these 3 facts we could then calculate the planes approximate speed/mph. on film.
1] Plane length- 159 ft.
According to Wikipedia Fl. 175 was 159 ft. long
2] Number of Frames Plane Takes To Travel Own Length?
This was fairly easy to establish via this online frame by frame analysis: http://www.911conspiracy.tv/chopper5_HQ_slideshow.html
Here are my 2 screen shots from the above site , starting at frame 372, with my red circle circling the nose of Fl.175 as it first enters the screen from right to left:
[ You might need to click on/enlarge this image to clearly see the plane nose I have circled in red]
Then I simply clicked the "next" button at the website to advance the view one frame at a time, until the plane image was fully in view.
I count 6 frames before the plane image is fully in view at frame 378:
So now we can see that the plane travels its own length, 159 ft. in 6 video frames.
3] Speed of Frames Per Sec For Camera Used?
Now, we need to know the frame speed of the camera in question in order to calculate the plane speed per frame.
According to my sources, there were two frame speeds for video professionals available back in 2001, 15 frames per sec. and 30 frames per sec.
The Fox 5 sequence is apparently at 30 frames per sec.
Plane Speed Per Frame = 26.5 ft.
If the plane travels around 159 feet in 6 frames, then it is traveling at a speed of 26.5 feet per frame. [159 divided by 6= 26.5].
@30 frames Per Second
At an assumed camera speed of 30 frames per sec for a plane 159 ft long, that is 795 ft feet per sec., [26.5 x30]; which is 47,700 feet per minute [795 x 60]; which is 2,862,000 ft per hour. [47,700 x 60].
Fox Plane Speed = 542 mph ?
There are 5,280 ft. per mile, so dividing 2,862,000ft. [i.e the distance the plane would travel in 1 hour, expressed in feet], by 5,280 [the number of feet per mile] gives me a plane speed of around 542 mph.
Now, an airspeed of 542 mph at 1000 ft. altitude is no more technically feasible than is the officially claimed pre-strike speed for Fl. 175 of 598 mph - that speed has already been demonstrated to be technically impossible in the "Pilot's For 9/11 Truth " video linked to above.