Looks fake, as has been said, it is too perfect. Looks like it was originally a 4 plane formation that has been copied and pasted a number of times to provide the picture observed.
There are slight variations between the 5 aircraft as the "parade" arcs to the upper right.
A precision flying team can hold an amazingly accurate line (Blue Angels, Thunderbirds and Snowbirds come to mind here) and this is a basic banking formation shot in time-lapse.
I have a friend that does photos like that stitching multiple exposures together to make it look a bunch of planes. Problem is that they all look the same, including registrations and other markings. Neat effect, but not real.