LAS VEGAS Federal and airport authorities are investigating why an air traffic controller became incapacitated during a night shift alone in the tower of bustling McCarran International Airport in Las Vegas and fell silent. Kris Van Cleave, CBS News correspondent, reports that the air traffic controller of the incident was incoherent and eventually unresponsive until he was spotted by another air traffic controller returning from a break.
"The FAA is very concerned about this incident and what happened is unacceptable," an agency spokesman told CBS News.
You can hear the controller blur her words, confused flight numbers and otherwise incoherent before an alarming open-microphone incident has occurred, causing her to hear coughing and choking.
At one point, a pilot waiting on a flight asks to fly off, "Is there anyone who knows what he's doing?"
Later in the incident, one of the flights called, "I hate to ask, but do you have a supervisor?"
Another pilot answered: "Something is wrong."
"Something's going on up there," says another concerned pilot.
On Friday, the FAA changed its occupation rules to make sure that two controllers are in the tower before midnight.
"There were no security incidents during this incident," the federal aviation authority said in a statement that officials said they were 40 minutes long, during which time the female inspector apparently lost consciousness just before midnight.
"An air traffic controller at the Las Vegas Tower was disabled during the service," the agency said. She did not identify the controller or the cause of her inability to work.
Airport Director Rosemary Vassiliadis made a statement stating that the initial results reflect the FAA rating.
Five incoming aircraft remained in the air during the incident and ground-based aircraft held positions or communicated with each other to ensure safety during the movement, the FAA said.
Air traffic records available on the Internet show that commercial airline pilots have difficulty understanding the controller during take-off, landing distances and taxiing instructions. Some start talking to each other that something is wrong.
At one point, the controller sounds drowsy and apologizes for the radio. He says she "chokes a bit". Minutes later, she gives the numbers of an aircraft wrong. Finally, her microphone opens for the sound of coughing and grunting.
She does not answer the request of a pilot before the sound of a man's voice is heard in the room as to whether the woman is okay.
Officials said a male controller who had been in the break was told to return to the tower. Paramedics responded.
The FAA said the woman was on administrative leave and the agency ordered two controllers to be in the tower during the full hours.
McCarran is one of the 10 busiest airports in the United States. The unidentified controller worked just over an hour before the trouble started, and communicated with pilots from 29 aircraft before it was replaced, the FAA said.
The head of the National Air Traffic Controller Association, Paul Rinaldi, issued a statement praising the work of thousands of union members across the country and promising cooperation in the FAA investigation "so that all the facts are known".
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