Go to -3h 19min.
The ship on the left goes very close to the support and appears to stop on the other side. My guess is that it was hung up on something and they gave the engine a burst and pulled the support down. It came down in seconds.
What you see either side of the support at the base could be the water from the prop hitting it from the other side and being thrown to the sides, then it suddenly collapses.
