Two drives dropped from the same height can end up in entirely different conditions, and the difference is whether they were spinning. Powered off, the heads are parked and the mechanism tolerates real shock. Running, they are flying a fraction of a hair above the platter — and an impact closes that gap.
$ cdr diagnose /dev/sda → Device: Seagate ST1000LM048 · 1 TB · 2.5" → Status: DROPPED — head crash / heads not reading → Client: confidential · Newmarket, Cambridgeshire $ cdr engineer-working → Donor heads matched: from stock · 0 days wait → Head-stack swap: complete → Imaging: 0.81 TB / 1.00 TB (81%) $ cdr verify → ✓ photos — 58,210 files → ✓ university_work — 3,940 files → ✓ everything reachable — recovered
Almost everything about the prospect of recovery follows from that single fact.
Modern drives park their heads off the platter when idle. A drive dropped while off has a good chance of nothing worse than a stuck head stack or a shifted spindle — frequently a complete recovery.
The heads fly microns above a surface spinning at 5,400 or 7,200 rpm. An impact at that moment can drive them into the platter, scoring the coating. That damage is permanent.
If the drive kept running after the impact, damaged heads continued to travel across the surface. This is the scenario that turns a recoverable disk into a partial one, and it is entirely avoidable.
First, do not power it on to see whether it still works. That is the instinct and it is the single most damaging thing available, because a drive with a disturbed head stack will drag those heads across the surface the moment it spins up.
Second, do not shake it, tilt it or listen to it by holding it to your ear and turning it over. If something has come loose inside, moving the drive moves that debris across the platters.
Third, pack it properly and send it. Anti-static bag, firm padding, a box with room around it. A drive that has already suffered one impact should not suffer a second in the post.
Liquid as well as impact? If the drive was dropped into water or a drink went over it, do not dry it out and do not power it up. A wet drive that has never been spun is a far better prospect than a dry one that has.
Impact damage is mechanical-class work from £300 +VAT, agreed in writing after the free diagnostic. Where platter scoring is present we will say so at that point, along with a realistic estimate of what proportion is likely to come back.
Clean-air work carries a 50% deposit because the costs commit when the work starts. The balance is payable only if the recovery succeeds.
Yes, enough to back it up today. A drive that survived an impact may have sustained damage that only shows up under load weeks later. Copy everything important off now while it is still cooperating.
Possibly. Drives are more fragile than their casing suggests, particularly while running. If it has developed any new noise or slowed noticeably, treat it as damaged and stop using it.
Do not dry it and do not power it on. Salt water is considerably worse than fresh but both are workable if the drive has not been spun since. Send it as it is, sealed in a bag.
It ranges from everything to very little, decided almost entirely by whether it was running at the time and whether it ran afterwards. The diagnostic tells you which case yours is before you commit.
No. Opening a drive outside filtered air introduces particles onto a surface with sub-micron clearances. A single dust particle under a head is enough to score the platter.
Entirely plausible. Impact damage frequently causes gradual degradation rather than immediate failure, and a drive can run for a long time on heads that were disturbed by an old knock.
Every repair is backed by a 10,000-piece donor store, opens with a free written diagnostic, and on most jobs is no fix, no fee. Begin today.