i'm leaving for distant lands next week on an airplane and i thought that i'd take my acoustic with me. the problem is that i only own one of those soft guitar bags with the fluffy interior. is it safe to put my guitar in the cargo hold in just a bag?
I'm going to Rhodes this saturday and I'm taking my acoustic with me. I have a hard case and a humidifier. Plus I have an insurance for it, so if the airline people break it I'll get a new one.

Is ~15% a big difference in humidity?
If your gonna transport your guitar on a plane make sure you have a hard case. I've also heard that you should detune your strings a half step or else your guitar neck might be damaged. (has to do with air pressure or something)
Well I work for an airline so I guess I got a little bit of inside info. First of all always check your guitar as a claim at gate bag. That way you can pick it up right when you get off the plane and more importantly it means it's loaded last and nothing is stacked on top of it. Second ask if they can throw it into the pit with animals in it. Planes have at least one pit thats heated that they put animals in. If it's with the animals, it's not subject to the extreme cold of the other pits. Usually it's in the heated pit if its a claim at gate anyways but it's good just to make sure.