Your best bet (other than not flying) is the gate check route, but to do that you'll need to convince the airline to let you do that when you check in and again at the gate. At the gate, you'll get a special tag from the clerk, then you carry it down to the plane's door, and leave it there. A baggage carrier will take it down to the cargo hold and it will be waiting for you as you step off the plane at arrival. Most of what's going this way will be baby strollers - but most other stuff that's big doesn't get this far (golf clubs, skis, etc.). That stuff needs to be checked prior to security.
Often delicate oversize stuff can come onboard if you buy it a seat, but I'm not sure that they'll let you do that with a hardshell bass case as it's probably bigger than what would fit in a seat. This is intended more for saxes, trumpets, violins and the like.
Finally, just to make this all even more frustrating, unless you purchase special travel insurance for the instrument beforehand, I think it's unlikely that you will be able to depend on any insurance from the airline if you check it. They have a limit of $750 or $1000 for personal items in a regular suitcase, but they provide no coverage for any other items you might check unless it is in a certified ATA-approved case (e.g., a real Anvil), and even then, it's probably subject to a limit well below what your instrument is worth.
The airlines don't make it easy but this is definitely out on the edge for them. It may be easier to send your instrument ahead if you can do that (yes, I know that's not much fun either, but at least you can insure it fully).
David Fung