hey, I am a Colombian helicopter pilot and I flew on a tuna boat around a year on Panama.
i) Can you eat as much Tuna as you want when not flying?
Yes you can, but all the time you are flying.
ii) Can the Captain (of the boat) order you to launch even if the weather is $hit?
Not, he can't is your last desition.
iii) What is the most hours you have flown in a 24 hour period?
daily between 6 and 9 hours all days without rest until you fill the boat
and pay is a !!!!. But nice experience.
iv) Who does all the maintainence?
A mechanic in the tuna boat. He goes with you.