Updated at 2:42 p.m. ET
BOISE, Idaho A United Airlines captain suffered a heart attack while piloting a plane from Houston to Seattle and passengers stepped in to help with a doctor performing CPR and an off-duty pilot assisting in the emergency landing in Idaho.
Ada County Coroner Erwin Sonnenberg identified the captain as 63-year-old Henry Skillern of Humble, Texas. Sonnenberg performed an autopsy on Skillern late Friday morning and confirmed that he died at a Boise hospital of a heart attack.
The captain was piloting United Flight 1603 from Houston to Seattle when the emergency occurred Thursday, forcing an off-duty pilot to take over control of the plane. Two Madigan Army Medical Center doctors onboard performed CPR, according to Jay Ebbeson, a spokesman for the hospital at Joint Base Lewis-McChord.
Ebberson says the two are captains and radiology residents who were returning to the base near Tacoma, Wash., from a medical course at Fort Sam Houston in San Antonio. They were unavailable Friday to talk about the incident, he said.
The flight diverted to Boise for the medical emergency. It landed safely about 8 p.m. local time and was met by paramedics who took the pilot to the hospital. The Boeing 737-900 had 161 passengers and a crew of six on board.
The captain was still alive when he arrived at Saint Alphonsus Regional Medical Center but died overnight while undergoing treatment, spokeswoman Jennifer Krajnik said Friday.
The news lit up social media in the early morning hours Friday, with dozens of tweets sent out about the pilot's death.
Passengers told CBS Seattle affiliate KIRO-TV the crew asked for a doctor and then saw CPR being administered.
"I am sad to confirm that our co-worker passed away last night. Our thoughts are with his family at this time," United spokeswoman Christen David said in an email.
Another off-duty United pilot was onboard and helped land the plane, David said.
Pilots are required to get medical certificates that show they don't have major heart problems, according to the Federal Aviation Administration website.
David says another pilot flew the original plane and passengers to Sea-Tac Airport.