Recovering partitions from disk image?

[snott]

Hello FreeBSD gurus,

I recently had the pleasure of trying to recover a failed RAID1 array.  It
consisted of two 120GB disks in mirrored configuration.  Both drives have a
ton of bad sectors, so bad that the 3ware RAID card stopped recognizing that
there was a mirror at all.  Having no other options that I could think of, I
pulled the drive with the one with the least read errors, directly connected
it to ATA bus and used GNU ddrescue to make a disk image with only about 7
read errors.

Neither fdisk nor bsdlabel can read the disk image.  I wonder if there's
some funny data at the beginning of the hard drive the 3ware card used for
RAID configuration?  If this is true, is there a way to search for the
beginning of the real fdisk data and lop it off to make a possibly valid
disk image?

Here's how it was laid out before the crash:

Filesystem      Size   Used  Avail Capacity  Mounted on
/dev/twed0s1a   4.9G   2.8G   1.7G    62%    /
/dev/twed0s1e   9.8G   5.0G   4.0G    56%    /var
/dev/twed0s1f   9.8G   952M   8.1G    10%    /usr/home
/dev/twed0s2e    88G    15G    65G    19%    /mnt

TestDisk can find all the old partitions, but I can't figure out what if
anything it can actually do with them.  It only finds them if I do a "quick
search" and specify "Non partitioned media" as the partition type:

-----------------------------------------------------------------
Disk disk0.img - 123 GB / 115 GiB - CHS 15018 255 63  

     Partition                  Start        End    Size in sectors  

   P UFS                      0  15 31   652 196  7   10485760 [/]   
   P UFS                    652 196  8  1958  47 24   20971520 [/var]   
   P UFS                   1958  47 25  3263 153 41   20971520 [/usr/home]  
   P UFS                   3394  14 31 15017  14 27  186723492 [/mnt]         

Write isn't available because the partition table type "None" has been
selected.
-----------------------------------------------------------------

It doesn't look like scan_ffs works on files.  
Can I use the testdisk output to extract some portion of the disk image and
mount it somehow?

Any suggestions on how to get to the data is much appreciated.  I've learned
the hard way that RAID1 is no substitution for a backup plan :/

Thanks,
Skye

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