But the horn sound was probably white noise so it might have gone right past anyone nearby. I know I don't think anything when I hear the horns in Baltimore, having stayed there many times for conferences and the like.
You CAN see smoke coming out of the ship shortly before impact too though. Just awful. It could be a bit...Titanic-esque, in that by the time the problems of the ship became clear to the captain, it was too late. It can't be easy to stop a ship of that size. The last time the power came back on, it was like, IMMEDIATELY before impact.