Hypoxia case
Not a commercial turbojet, but Helios comes to mind.
Jan 4th, 2018 US Coast Guard searching for missing aircraft
NEW ORLEANS – The Coast Guard is responding to an aircraft emergency in the Gulf of Mexico approximately 118 nm north of the Yucatan Peninsula, Thursday.
Watchstanders at the Eighth Coast Guard District command center in New Orleans received a report from the North American Aerospace Defense Command, Wednesday evening that one person aboard a privately owned Cirrus was unresponsive likely due to hypoxia. The pilot was leaving from Oklahoma City and was headed to Georgetown, Texas. Naval Air Station Joint Reserve Base New Orleans launched aircraft to investigate and reported the pilot was slouched over and appeared unconscious.
The Eight Coast Guard District command Center has been coordinating with SEMAR, the Mexican Navy. District Eight watchstanders directed the launch of a Coast Guard Air Station Corpus Christi HC-144 Ocean Sentry aircrew, a Coast Guard Air Station Clearwater HC-130 Hercules aircrew and a Coast Guard Aviation Training Center Mobile HC-144 Ocean Sentry aircrew to search for the aircraft.