The comparison of the sailship, submarine and the airplane doesn't really hold, though.
A sailship travels for weeks or months, has not a single piece of automation and has to be maintained during the journey.
Similarily the submarine is meant to travel for long periods of time during which it has to be operated and maintained.
Both of those are designed to be self-sufficient, so they have to provide facilities for the crew, and the crew grows due to maintenance required, medical and battle stations.
The airplane travels for 16 hours tops and is supported by a sizable crew of engineers, ground control, and for passenger planes, cooks and cleaning personell, on the ground.
Right. Warships try to be self-sufficient and able to deal with battle damage, which means a large on-board crew. The biggest Maersk container ships have a crew of 22. Nimitz-class aircraft carriers have about 3,000, plus 1,500 in the air units. US Navy frigates have about 220.
If you want a sense of how many people are behind an airline flight, watch "Air City", which is a Korean drama series about a woman operations manager for Inchon Airport. The Japanese series "Tokyo Airport" is similar. Both were made with extensive airport cooperation, and you get to see all the details. (This, by the way, is typical of Asian dramas about work-related topics. They show how work gets done. US entertainment seldom does that, except for police procedurals.)
A sailship travels for weeks or months, has not a single piece of automation and has to be maintained during the journey.
Similarily the submarine is meant to travel for long periods of time during which it has to be operated and maintained.
Both of those are designed to be self-sufficient, so they have to provide facilities for the crew, and the crew grows due to maintenance required, medical and battle stations.
The airplane travels for 16 hours tops and is supported by a sizable crew of engineers, ground control, and for passenger planes, cooks and cleaning personell, on the ground.