The 47-year-old from the north west was arrested by armed officers who met flight QR23 from Doha, Qatar, when it arrived at Manchester Airport on Tuesday, escorted by an RAF Typhoon jet.
A spokesman for Greater Manchester Police said: "Following his arrest he was assessed by medical staff and again by a mental health team. He was subsequently sectioned to allow for a fuller assessment and appropriate treatment."
The alert was sparked by fears of "a possible device on board" but Greater Manchester Police pronounced the Airbus A330-300 clear after searching it.
Some of the 269 passengers on the flight described seeing the fighter come close to the civilian aircraft as it flew towards Manchester.