Strange flash drive behavior--random deletions

[Dreamstalker]

I've had my current flash drive (Corsair Voyager 4GB) for a few years now, recently purchased a new one. I travel with my flash drive loaded with PortableApps and a few miscellaneous files. I have about 8 separate folders.

I get home from a trip, to find some folders/files that were on the Corsair drive erased or showing up as empty

--Portable Thunderbird: initially the folder was reading as empty, a start/abort of the delete process somehow restored everything.
--Portable Firefox; OK except for the bookmarks
--OO Portable: gone
--Various photos: gone (I have a backup)
--Music (one song from BT and clips from TV shows for a forum project): gone
--Utilities (AVG, CCleaner, etc): gone (I have an intact backup)
--Running invoice for a friend/client, and a few other small files: empty, although the size and "last modified" stamp is intact. I can most likely recreate the invoice as I do have a printout from a couple months ago.

I accessed the flash drive before coming back here, and everything was fine.

I'm not saying the airport X-ray scanner did anything, but it does seem like an odd coincidence that this happened after the fourth trip though the scanner. If the drive was failing, I would expect it to be less particular in what it decided to eat.

Any ideas?

[LionMan]

Since everything came out fine, I suggest backing up everything on the drive and then do a low-level format on the drive. You might have some bad sectors or the hardware is failing. A low-level format (not the quick format), should detect and prevent writing on the bad sectors at least. If you see a lot of bad sectors (large change in drive capacity), I would suggest throwing it away because when they start going bad, they go downhill quickly.