How?
How does he go unnoticed by two barges, even after lighting the flares? And one was at night even!
Aren't they equipped with enough people to keep watch of the ship's surroundings at all times?
I guess the captain etc. of the transport barges weren't paying attention.
The second one at night was after the barge had gone by, pretty much.
"Did you make coffee? Make it!"--Cheyenne.