Ballast Watch Planning With Predictive Circadian Data

A VLCC in ballast from Rotterdam to Ras Tanura carries no cargo, but it carries the same bridge team, the same watch cycle, and the same circadian debt as the loaded leg. The temptation is to treat the ballast leg as recovery time. The data says the ballast leg is often where the worst cognitive troughs accumulate unobserved.

On a VLCC leaving Rotterdam in ballast for Ras Tanura, the loading terminal stress is over. The port-call paperwork is filed. The next charterer conversation is 15 days away. The ship-time of the bridge team drops. Watches still happen, but the pressure to perform them sharply often drops with them. Masters reduce daywork. Chief Mates catch up on paperwork. Second Mates sleep whenever they can. The watch board still shows a 4-on-8-off structure, but the informal tempo of the ship has gone soft.