A registered emergency room nurse who came to the aid of an ill passenger on board a United Express jet on Wednesday morning said she realized something was "very wrong" when she and others also became light-headed during the flight.
The crew of Flight 5622 from O'Hare International Airport declared an emergency en route to Bradley International Airport in Connecticut and put the plane down at Buffalo Niagara International Airport at about 11:40 a.m after a passenger lost consciousness and the pilot worried the cabin had lost pressure, the airline said.
Before the plane landed, however, the pilot dove the plane more than 20,000 feet in just minutes.
Mary Cunningham, of Niantic, Connecticut, said she responded to the crew's call for medical help on the plane when one passenger became ill.
"The passenger was lethargic. She was responding but her color was off. She didn't look good. We got her some oxygen. She was much more alert after getting the oxygen," Cunningham told NBC Connecticut.
But the end to that drama was short-lived.
"Then I went back to my seat when she was feeling better and all of a sudden the woman sitting behind her passed out, unresponsive. It was multiple people affected," she said. "The flight attendant and myself started not feeling very well while we were in the middle of the flight helping out. I had to sit down. I was short-of-breath, light-headed [and] didn't feel great."
The Federal Aviation Administration said initial information indicated the Embraer E170 jet may have had a pressurization problem, but that turned out to be incorrect.
The flight was operated by SkyWest Airlines, and a spokeswoman said the pilots rapidly descended "out of an abundance of caution." For nearly eight minutes, the plane descended at a very steep incline, dropping as fast as 7,000 feet per minute, flight tracking service FlightAware said.
"It was scary," said passenger Larry Johnson, who said he thought of the airline passengers killed on Sept. 11, 2001. "A lot of people with their heads down praying. It just felt like a re-enactment."
Marissa Snow, a spokeswoman for the St. George, Utah-based airline said the jet landed safely and that three passengers lost consciousness. An additional 15 adults and two children were evaluated upon landing, but none required treatment outside the airport, airport spokesman C. Douglas Hartmayer said.
"Anyone who said they didn't feel well was treated at the gate," he said.
The plane's oxygen masks did not deploy. FAA investigators said they were looking into the incident.