Over the winter lay-up period we ran a calibration audit across the vessels on our service contract. The intention was housekeeping — confirm what was due, schedule it, move on. What came back was interesting enough to write up, because the pattern was not the one we expected.
What we looked at
Thirty-four vessels were in scope: coastal ferries, general cargo tonnage and a handful of trawlers, all with at least one Kymaros instrument fitted and all on a contract that includes periodic calibration. For each vessel we pulled the instrument register, checked the last recorded calibration date against the interval the type approval requires, and physically verified the certificate was aboard.
The headline number
Eleven of the thirty-four had at least one lapsed magnetic compass calibration. Not lapsed by a week — the median overrun was fourteen months. Every one of those vessels had passed a port state inspection during the overrun period.
That last detail is the uncomfortable part. The paperwork chain that is supposed to catch this did not catch it, in eleven cases out of thirty-four, over a period long enough that it cannot be dismissed as timing.
Why it happens
The failure is almost never refusal. Nobody decides to skip a compass swing. What happens is that the deviation card gets renewed on the vessel’s own schedule, which drifts, while the instrument register sits in a folder that only gets opened when something breaks. There is no forcing function. A radar that fails announces itself; a compass that has quietly drifted three degrees does not.
The role of crew change
Overruns clustered on vessels that had changed masters within the audit window. Handover notes cover the things a master needs on day one. Calibration intervals are a day-ninety concern, and they fall through the gap between the outgoing officer who knew and the incoming one who has not been told.
What we changed
We now push a calibration due notice to the technical superintendent ashore rather than to the vessel, ninety days out and again at thirty. Ashore is where the continuity is. This is not a clever intervention and it should not have taken an audit to arrive at it.
We also stopped accepting a verbal confirmation that a swing had been done. The certificate scan goes into the register or the interval stays open.
On the bench itself
For anyone wondering about the reference: our compass calibration bench at Perama is certified to ±0.15° heading accuracy and is itself re-verified annually against a national standard. Bench units carry a serial prefix of KLB- and the serial appears on every certificate we issue, so a certificate can always be traced back to the specific bench that produced it. If you hold a Kymaros calibration certificate without a KLB- serial on it, it did not come from us.
If you run a fleet
Pull your instrument register this month and check it against the intervals rather than against your memory of the intervals. Our experience says roughly a third of you will find something.