Here are two examples of fake UA175 photographs I quickly made in Photoshop using Flight Simulator to generate the correct image of a Boeing 767. It took about 1 hour to manufacture each image and they aren't particularly convincing, but it does demonstrate that photographic forgery is achievable for the layman.

Please note the second image is deliberately showing a Boeing 767-300 unlike the Boeing 767-200 below:

If this is what can be achieved by a novice Photoshop user in an evening then imagine what a skilled team of professional forgers could achieve in a few days.

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