Exhibit D (upper right) shows what an American Airlines Boeing 757 would actually look like in the video frame, based on the 3-D simulation posted to You Tube on July 1, 2006: http://prisonplanet.com/articles/july2006/010706casestudy.htm. (The aircraft would probably appear more blurred than is shown here. The outline has been highlighted to show the size and dimensions clearly.) When the pixel difference obtained from the real video frames is superimposed on the simulated 757 (right), we see that 1) the position of the tail is significantly different, 2) the nose of the aircraft is visible in the simulation, but not in the actual frame.
Conclusion: If the "911 Case Study" simulation is correct, then the object in the video frame is not a Boeing 757.