Photogrammetry is quite limited with only a single camera, so I attempted to analyze the Security Camera images frame by frame, measuring the distance the fuselage (and only the fuselage) traveled from frame to frame. Since the aircraft is basically traversing a straight line (down the runway), I used fixed points in both the foreground and background as references. My technique was to draw 2 straight lines (through foreground and background reference points) on the images, one marking the position of the nose of the aircraft on each image, and one marking the position of the nose from the previous image. I could then determine how far the fuselage had moved forward from the previous image.
This technique seemed to work for the first few frames, but then seemed to fail in the later frames as the aircraft's speed begin to skew towards 160 knots in the later frames (161 being the highest I measured). I assumed this might be due to greater pixilation, greater view angles or some other artifacting in the images, as the aircraft got further away from the camera. I also assume there's no way this aircraft could have been accelerating towards 160 knots after touchdown.
The results also seem to indicate that the time stamps on the images are quite accurate.
Some portion of the aircraft is recorded in 9 images. I'm only posting the results for the first 3 measured frames because they are consistent and the following frames start the skewing towards 160 knots.
I used the following formula in Excel to calculate speed. I'm an American so I like to measure in feet
ESN = 1/TD*DTF*3600/FNM
Where:
Assumed Aircraft Length = 123ft 3in
ESN = Estimated speed in knots/hour
TD = Time Difference from previous frame to current frame
DTF = Distance Traveled in Feet
FNM = Feet per Nautical Mile = 6076.1155
Frame 19.828 - First reference frame, marked nose position only
Frame 20.031 - TD = .203 sec, DTF=53.4ft, ESN =
155.9 knots
Frame 20.421 - TD = .390 sec, DTF=102.7ft, ESN =
156.0 knots
Frame 20.828 - TD = .407 sec, DTF = 106.8ft, ESN =
155.5 knots
Again the speeds begin to skew towards 160 knots after this, which can't possibly be right.
Now if someone else knows where the camera is, has access to an accurate scale drawing of the airport (and immediate surroundings), and can reference structures in the background, they should be able to determine where the aircraft was located on the runway in each frame. But I leave this task to someone else.
