at the same time, yvonne morrow and her group are looking over the river. >> we were looking across at new jersey and pointing things out when all of a sudden we heard this pop and it made us look up. >> seemingly from out of nowhere, a small plane appears as the helicopter is ascending. >> oh, my god! >> a devastating collision is captured on video. the remains of both aircraft fall to the water. captain corcoran is almost directly below the falling debris. >> basically at this point is when we had seen two major splashes. i didn't know what it was, to be honest with you. the corner of my eye, just at this point right here. and it just went plop, plop. what the crew members heard was people screaming. that's when i realized it was a small plane and a helicopter. >> emergency responders arrive on the scene almost immediately. >> within seconds, it seemed, nypd aviation, the helicopter came swooping down and dropped one of their rescue divers into the water. it was just amazing. >> stunned bystanders watched the tense scene unfold. >> you couldn't believe what you were seeing. it really