When a passenger with an accent tried to alert the co-pilot in the cockpit, the co-pilot became alarmed and notified air traffic controllers, according to a recording of the radio exchange from the website LiveATC.net.
"The captain has disappeared in the back, and I have someone with a thick foreign accent trying to access the cockpit right now, and I've got to deal with this situation," the co-pilot said.
Indianapolis-based Chautauqua Airlines, which operates the flight for Delta, said the pilot had decided to take a bathroom break about 30 minutes from LaGuardia after controllers told the crew to expect to be in a holding pattern.
The sole flight attendant on board had entered the cockpit when the captain left because security rules require two crew members in the cockpit at all times. The Embraer 145 commuter jet was carrying 14 passengers.
The captain gave the passenger a password to get into the cockpit, but the co-pilot and flight attendant were still doubtful, the recording shows.
"Someone with a thick foreign accent is giving me a password to access the cockpit, and I'm not about to let him in," the co-pilot said.
As the minutes ticked by, a controller told the co-pilot to consider declaring an emergency, which would give the plane priority over all others.
"OK, Chautauqua, you guys ought to declare an emergency and just get on the ground," the controller said.
The captain eventually freed himself from the lavatory and came on the radio to tell controllers there was no danger.
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