HDD head crash
This story is from a recent data recovery case where a RAID 1 was shipped to our labs, the RAID comprised of 2 Seagate 2TB hard disks.
Initially the client thought that it was a RAID 0, however after a brief investigation it was discovered that it was a RAID 1, (mirror), thankfully as one of the disks was completely destroyed due to a head crash, and the hard drive was left running for some time, which clearly exacerbated this situation.
The destruction of the disk was the most severe we had seen, please take a look at the pictures for confirmation.
Clear deep scratches on the platter can be seen.
All 6 heads have been completely destroyed! this is the most extreme case of head failure we have seen to date.
The RAID was running in a rack at a data center, and sadly was left running for some time before the issue was picked up by the technicians.
If your hard disk has been dropped, or knocked or is making strange noises it is possible that you have head failure & that the heads have come into contact with the disk surface, thus literally scraping off the data and destroying any chances of data recovery, so our advice is; if you drop or knock your disk do not re-power it up, as further damage will be caused, also if your drive does start to make unusual noises, power it down as safely as possible, and do not attempt to try connecting it again to a computer system.