Pattern quiz

Can you read a blackout?

Five alarm-log snapshots. Call the cause before you open the answer. Every scenario is a generic engine-room pattern — no vessel, no owner, nothing traceable to any ship.

One rule that carries all five: read the timestamps, not the order the alarms printed.

Snapshot 1 of 5

10:14:02  DG2 REVERSE POWER — TRIP
10:14:02  DG1 OVERLOAD
10:14:03  DG1 GENERATOR BREAKER OPEN
10:14:03  MAIN SWITCHBOARD — BLACKOUT
10:13:58  DG2 FUEL RACK AT MINIMUM

One set drops, the other cannot hold. What failed first?

Snapshot 2 of 5

03:41:11  BOW THRUSTER START REQUEST
03:41:12  BUSBAR VOLTAGE 380 V → 291 V
03:41:13  DG3 UNDER-VOLTAGE
03:41:13  PREFERENTIAL TRIP STAGE 1 — NON-ESSENTIAL
03:41:15  BUSBAR VOLTAGE RESTORED 379 V

Manoeuvring, thruster started, lights dipped, non-essentials shed. What is this?

Snapshot 3 of 5

18:02:40  DG1 GEN VOLTAGE 8.1 kV  (nominal 6.6 kV)
18:02:41  DG1 EXCITATION — HIGH
18:02:44  DG2 GEN VOLTAGE 8.4 kV
18:02:47  DG4 LOSS OF EXCITATION (40Q) — TRIP
18:02:47  BLACKOUT

Two sets read high, a third trips on loss of excitation. Where is the fault?

Snapshot 4 of 5

21:55:00  ME LO INLET PRESS 1.9 bar (LOW)
21:55:00  ME LO INLET TEMP 61 °C
21:52:00  ME LO INLET PRESS 2.4 bar
21:52:00  LO FILTER DIFF PRESS 0.9 bar (HIGH)
21:56:10  ME SLOWDOWN — LO PRESS

Main engine slowdown on lube oil pressure. What is the actual defect?

Snapshot 5 of 5

07:30:00  EMERGENCY GENERATOR — AUTO START OK
07:30:12  EMERGENCY GENERATOR — RUNNING, ON LOAD 0 kW
07:31:00  EMERGENCY SWITCHBOARD — NO VOLTAGE
07:31:05  TEST COMPLETED — SATISFACTORY

The weekly test passed. Did it?

Your score

0 / 5

5 snapshots left to call.

Read the casualty files

Keep your results

Have this sent to you, with what usually comes next.

The five alarm-log snapshots with the full reading of each one, plus the leading indicator that was visible before every blackout in the set — the signal you can look for on your own ships next week.

Now: the five snapshots, the causes, and the signal that preceded each.
Day 3: how a single fault becomes a three-week cascade — the mechanism, not the anecdote.
Day 8: turning alarm history into a leading indicator across a fleet, with the trade-offs stated.