Newbie who has spend the day reading threads related to my situation but confused by the remarkable coincidence of having BOTH my identical (infamous it seems) Seagate 7200.11 data drives die together. Drive one powers up and spins, produces 11 consecutive clicks and then spins down. Drive two spins up, produces 44 clicks with a pause between each 4 and then spins down. Drives not recognised in BIOS or OS. These are the infamous SD15 500GB drives that have left a tale of pain and suffering for various reasons over the years.

From my general reading on threads in this forum it would seem I have mechanical damage of some sort...but is it just coincidence that both drives died together? I have tried moving them to a different computer and an external USB bay but the behaviour is consistent. The two drives contain the same set of valuable data so I have two chances at recovery. They were my "data" and "backup data" drives. You can work out the rest...

Do I just send these off to a recovery specialist in Europe (closer to where I am) or do I roll up my sleeves and start playing with Serial Interface options I am reading about?

I'm afraid the first option is only viable in this situation.
The behaviour you are describing is typical for heads damage and these drives are also known to be prone to platter damage.
I would suggest that you do not power up the drives again and consult a pro.

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