HellFireMC

Hi guys. Just want to say this isn't incredibly urgent, this is more out of annoyance and curiosity than anything else. Yesterday I spent around 2 hours creating an airship which I made for the Archimedes ships mod. This morning I load my world, work on it a bit more, and it crashes. I try to gain access to the world twice, both times it fails. I try once more, gain access to my world, but the airship is gone. I was in creative after having made the ship, but just fell down into the empty space where the airship would've been in my world. Is this a bug or what? An answer would be much appreciated. Sorry for spelling am on phone.