Data Recovery Case File · Drones & Aerial · The Sea Landing

Dried is not decontaminated: a drone's sea-soaked microSD, the corrosion clock, and the holiday footage recovered

The accident report was admirably concise: while on holiday, the drone "unfortunately landed in the sea." Recovered from the water, dried out, its 128GB SanDisk microSD now registers on nothing — his laptop reads every other card fine, so the fault is cleanly isolated to this one. The card was two weeks old; the footage was the holiday's. And his enquiry carried a calibrated hope worth addressing directly: he'd researched, and understood "it's very likely the data can be recovered." Broadly right — with two corrections that decide whether "very likely" stays true: what salt water actually is to electronics, and what drying doesn't do about it.

Calibrating the hope: what the sea leaves behind

His research's optimism has a sound basis — a microSD is a sealed monolith with no moving parts, and the memory inside routinely survives immersion — but the optimism has a clock on it, and the clock is chemical. Sea water is the harshest common liquid electronics meet: aggressively conductive while wet (shorting circuits the moment power arrives) and aggressively corrosive after, because drying removes the water and concentrates the salt — a residue that keeps attacking contacts, traces and the card's fine structures indefinitely, drawing moisture back from the very air to continue its work. "Having dried" is therefore the trap phrase in every sea-water enquiry: a dried card feels resolved while its corrosion is still on shift, and the two habits that most reliably convert "very likely recoverable" into "recovered" are the two he'd already half-performed — no repeated power-up attempts (each connection pushes current through salt-bridged circuitry) and promptness (his card arrived weeks, not months, into its corrosion timeline, with the damage still superficial). The non-recognition itself decoded conventionally: the card's exposed contacts and controller interface salt-compromised, the sealed memory behind them untouched — the standard sea-water autopsy, caught early.

The recovery — chemistry first, then the chip

Decontamination led, as it must: the salt residue neutralised and cleaned from the card's contacts and accessible structures, halting the chemistry before any further electrical conversation. The card's controller had taken the exposure's real damage, so the route ran past it: test points exposed and mapped against the VNR's references, the memory read out directly and in full, and reconstruction performing the controller's duties offline — error correction, descrambling, layout — until the drone's filesystem rose whole from the dump. The holiday came back as footage: the aerial video of two weeks' flying, including — inevitably, and intact — the final flight's record of its own descent, verified by playback across the card and delivered on new media. The card itself, salt-scarred and two weeks old, retired to the report; the drone's fate stayed between him and the sea.

Outcome

Full recovery, hope vindicated on schedule — and the drone-owner's drill this page exists to publish, because aerial photography puts more cards over more water than any hobby in history. When a drone ditches: retrieve the card, resist the urge to test it — every "will it read?" attempt is powered current through salt — skip the rice, the airing cupboard and the hairdryer (drying concentrates; it doesn't clean), keep it cool and enquire promptly, because corrosion is the only part of this story that worsens with time. And the habit that beats the drill entirely: offload flight footage the same evening it's shot — a drone's card should never hold more than one day's flying, because the aircraft's whole job description involves the possibility of not coming back. His footage did. The margin was chemistry, and days.

Our case files are drawn from genuine enquiries received by our laboratory over the past ten years, anonymised to protect client confidentiality. Each one describes the diagnostic and recovery procedure our engineers apply to that fault, using the equipment listed.