(CNN) -- A Boise, Idaho, airport tower recording surfaced Friday that offered details of the crisis aboard a United Airlines 737 after its captain suffered a heart attack. The captain, whose name has not been released, died at a hospital after Flight 1603 made an emergency landing.
"We got a man down, chest compressions going on right now," said an unidentified crew member on an air traffic control radio frequency. "I'm not sure too much right now on status."
The flight crew coordinated with air traffic controllers about how the plane would meet up with first responders at the airfield.
"I'll just stop on the runway, and get on the other side of the aircraft and taxi off the runway, and then ambulance and maybe some air care needed off the runway," the flight crew member said on the recording.
The captain suffered the heart attack Thursday night, United said, while the airliner was en route from Houston to Seattle, prompting the aircraft to divert to Boise at 8 p.m. MT (10 p.m. ET). It wasn't immediately known if the captain was piloting the plane at the time he became incapacitated. Typically, there are two pilots in the cockpit so that during an emergency, either pilot can quickly take control of the aircraft. There were 161 passengers and six crew members aboard, the airline said.
Shortly after the emergency, crew members asked passengers over the cabin loudspeaker if anyone was a doctor, CNN affiliate KOMO reported, quoting a passenger.
On Twitter, an apparent passenger, @mannyseattle, tweeted, "Emergency landing in Boise, hope our pilot is OK. Loving the professionalism of the flight crew."
When the plane landed, paramedics boarded and rushed the pilot to Saint Alphonsus hospital, where he later died, hospital spokeswoman Jennifer Krajnik said.
Flight 1603's passengers waited at the Boise airport until United flew in another pilot from San Francisco, before they were able to continue their journey to Seattle. While awaiting the final leg of the trip, @mannyseattle tweeted, "People are tired, but calmed."
FAA regulations call for a medical examination every year for commercial airline pilots under age 40 and every six months for those over age 40. To pass the exam, they must not have an established medical history or diagnosis of coronary heart disease that has required treatment.
All airline pilots are required to get EKG heart checks at the age of 35. For those age 40 and older, annual EKGs are required.
And airline pilots are required to report any heart disease to the FAA, regardless of when they learn about it.
The mandatory retirement age for commercial airline pilots is 65.