Kevin Townsend was aboard a Hawaii-to-LA flight when he says the 757 jet dropped 600 feet to avoid colliding with another plane.
"The coffee pot in the back fell down. Passengers started screaming. There was a kid behind me who started screaming," he said. "It was noisy and violent and really terrifying, but over quickly, thankfully."
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It happened April 25 on a flight from Kona, Hawaii, to LAX. Passengers on United Airlines Flight 1205 said the plane felt like it was in a free-fall in the close call with a US Airways jet as the plane flew at 33,000 feet.
"I was weightless. We all were. Thirty-three thousand feet up in a cloudless sky, our plane had suddenly pitched into a steep dive," Sullivan wrote in a lengthy article online entitled, "Two Weeks Ago, I Almost Died in the Deadliest Plane Crash Ever."
When it was over, he said, "The voice of an audibly flustered flight attendant came over the speaker. 'OK. That was obviously unexpected.'
"A moment later, after we'd laughed and settled back into the friendly fiction of air travel as a mundane commute, her voice returned to notify us that 'the pilot took evasive action to avoid an aircraft in our flight path.'"
He said after the plane had safely landed at LAX, he asked the flight crew about it.
They told him the collision warning system had gone off in the cockpit, giving pilots about 15 seconds to react.
"The captain looked out the windshield, exclaimed 'Holy s***, there it is!' and immediately took the plane into a sharp dive. The first officer later told me the US Airways flight was 'certainly too close for comfort.'"
The FAA, NTSB and both airlines are investigating the incident.