NYC helicopter crash looks like a "catastrophic failure," Chopper 2's Dan Rice says

    NEW YORK CITY (WCBS/WLNY) -- An active investigation is unfolding after a helicopter took off in New York City and crashed into the Hudson River, killing all six people on board.

While the cause of the crash has not been determined, CBS News New York's Dan Rice, who reports from Chopper 2 and flies over the river daily, says eyewitness accounts and video point to a "catastrophic failure of the aircraft."

Witnesses saw helicopter spinning before crash

Some witnesses said they heard an explosion and saw the helicopter spinning. One described hearing a loud noise, "like thunder," then seeing "black particles flying" through the air.

"Booms and noises like that indicate some sort of mechanical issue," Rice said. "There's one video in particular where you see the main component of the helicopter, the fuselage, upside down. And what struck me, what scared me, is the main rotor system was gone. There's no main rotor on the helicopter and the tail boom was also gone, and it's just a vessel at that point with no direction."

Chopper 2 is the same model helicopter as the one that plunged into the Hudson River with a family of five tourists from Spain and a pilot on board Thursday. Rice said the video of the crash appeared to show the rotor system was lost before the helicopter hit the water.

"I can't say that I've ever seen an incident where such a major component of the helicopter has separated with no other aircraft or some other component hitting it. So I can't even begin to imagine, if this is true, how they would have lost the main rotor system," he said.

Crash video supports eyewitness accounts

While there is still a lot for investigators to confirm, Rice said that could explain why witnesses reported seeing the helicopter spinning.

"I'm not a pilot, I'm the reporter and the camera operator. But what I can tell you is the tail rotor is what keeps the helicopter from spinning out of control. That's your anchor, so to speak, that keeps the helicopter from being a top," he said. "If there's a problem with the helicopter, it can glide down to the river. But that's coming off of the main rotor blade. If they're separated, there's no control of the vessel. It's just going to end up the way we saw it, unfortunately."

The FAA and NTSB are investigating the crash. The Coast Guard also established a safety zone in the Hudson River.

What could have caused the Hudson River helicopter crash?

CBS News New York's Dick Brennan asked retired naval flight officer Armen Kurdian about the possible causes of the crash.

"Something physically broke in the shaft, something physically broke in one of the blades that would cause a massive vibration that would have essentially caused the rotor to shake itself apart," he said.

But Kurdian says the NTSB will also check if the aircraft was properly maintained and inspected.

He says a mechanical problem is another possible cause.

"Something just came loose. Something wasn't fixed properly. Something wasn't attached properly. Or perhaps one of the fasteners actually failed that caused the blade to actually come apart," Kurdian said.

Investigators will now sift through what was recovered on land and the water, and Kurdian says they could possibly get an answer quickly.

"The NTSB folks are gonna be looking at this, and once they pull it out, I think they are gonna have a solid idea of what happened within 72 hours, and I would be surprised if it takes them that long," he said.

Kurdian says since the helicopter was already in the air for a while, the chances are nothing was mechanically missing when they left, but something could have come loose in the air and then everything could cascade.

Dick Brennan contributed to this report.