Never again buy a non-removable backup drive!
Like some others on this forum, after a little more than a year I noticed that my Time Capsule seemed to be running warm, but I received no alarms or warning until it failed completely, and wouldn't power up.
I MIGHT have been able to claim a warranty under my Apple Care, if I could find the receipts, but in that case they would require me to surrender my drive (and my Time Machine backups, which I would not like to have fall into someone else's hands). The other alternative was to take the TC apart and salvage the hard drive, in which case I would presumably have access to my data, but that would void the warranty.
Since there was no way of recovering the data or at least zapping the drive so that no one else could read it, I opted to disassemble the TC and salvage the drive. Once I did that, I copied the Time Machine backups to another drive, using an inexpensive USB to SATA converter. I was never able to re-integrate that copy with Time Machine, but it didn't really matter, as I still had the originals in good shape, with multiple other backups.
Once I had saved the data, I added that drive to one of my five Drobos, and I am using it (plus two other somewhat suspect drives) for a tertiary backup drive.
I bought into the Apple mystique and bought three Macs after some bad experiences with Vista soured me on Microsoft. But this kind of a failure, just past the unreasonably short 1 year US warranty period, will make me very wary to buy an Apple product the next time around.
And I will never, ever, again buy a non-removable hard drive for use in a data backup application. If I could have removed the hard drive and replaced the rest of the TC, I might have done so, but their terms and conditions prevented me from doing so, so screw them. Maybe someone should file a class action law suit on behalf of the innocent believers.