Bob came out of the plane

[Bassim]

Are my sentences grammatically correct?

Bob came out of the plane, stumbled, and fell over. He was so drunk that he struggled to stand up again. "You can't throw me out now that we landed," he croaked at other passengers and flight attendants, who all gave him a hard stare.

 

[Charlie Bernstein]

Are my sentences grammatically correct?

Bob came out of the plane, stumbled, and fell over. He was so drunk that he struggled to stand up again. "You can't throw me out now that we've landed," he croaked at other passengers and flight attendants, who all gave him a hard stare.

Does he think they should have thrown him out before they landed?

 

[Bassim]

He thinks they might have thrown him out before they have even started flying.

 

[GoesStation]

He thinks they might have thrown him out before they [STRIKE]have[/STRIKE] even started flying.

See above.

 

[JMurray]

"You can't throw me out now that we've landed," he croaked…

My reading of this is that he was taunting them, saying they can't throw him out now because he's already out.

If your intended meaning is, 'He thinks they might have thrown him out before they even started flying', then perhaps something like:
"No use throwing me out now, you're all too late".