plane

[peter123]

Hi there,
Which preposition should I use in the following sentence?
Why 'on' is the one of the answers?

She didn't feel very well on OR in the plane.

Pete

[David L.]

Native speakers have learned their prepositions as we learn to speak, by copying what we hear. It is only when someone learning a language asks us, "But why do you use that preposition instead of..." that you force us to really think about our own language. So, thank you.
Someone else may be able to suggest another better reason, but I think it is to do with the size of the means of transport.
We would say:
on a ship but in a rowing boat

on a plane (like a Jumbo jet) but in a small plane that carries about 2-4 people
in a car
on a bus
on a spaceship, but in a rocket or in a space capsule
I've just thought : we say 'on a bicycle' but a bicycle is small. Perhaps the exception here is because we are really referring to the act of 'sitting on a bicycle'.
Has anyone one else some ideas here?