epic UFS crash

[siur]

Hello!

Some days ago I had situation with server running under FreeBSD 7.3.
Power supply unit suddenly broke down so server switched off
incorrectly. After that hardware raid controller marked one disk in
RAID1 as degrated. We've boot system from other disk and found out,
that almost all data was gone. To be exactly, it's looks like
everything created during last uptime had just dissappeared. I mean,
literally, server looked like from the past -- there was no data newer
than summer 2010. All databases, websites, user's files -- everything
was created/modified a year ago.
Fsck created much staff in lost+found directories, but, for example,
directories looks like empty for 'ls -la', but hex dump shows
information (that's, actually more like file, not a directory).

So, could anybody help me find out how it possibly could happen? (my
creepy story contains very few details, I understand). Does anybody
saw something like that?
I appreciate any ideas, all that shit just blowing my mind.

P.S. Generally, is there possibility to recover data from filesystem
with corrupted metadata?(My assumption was about corrupted meta, I
hope, superblock and data itself is alive).
P.P.S Sorry for my english 8(