While vessels are still approaching or waiting at the canal anchorages, the on-duty traffic controllers plan the optimal passage for each ship. They take into account the opposing traffic already in the Kiel Canal (NOK). The goal is to guide all ships through the canal as quickly as possible while ensuring safety and smooth operations.
Traffic on the nearly 100 km-long canal runs in both directions. Since mostly large seagoing vessels use the relatively narrow waterway, two large ships cannot meet just anywhere. Meetings are only possible at one of the twelve wider sections – called “passing places” – where one vessel waits until the oncoming ship has cleared. Light signals at these passing places (similar to traffic lights) tell ships when to proceed or hold. To ensure safe passages with minimal and brief waiting times, controllers must plan ahead and act with foresight.
Depending on a vessel’s length, breadth, draft, and cargo, ships are classified into six traffic groups (TG). TG 1 includes the smallest vessels and TG 6 the largest. Adding the TG numbers of two meeting ships yields the encounter factor. The canal is divided into sections with different maximum encounter factors based on its varying widths. On most stretches, the permitted encounter factor is either 6 or 7, allowing, for example, a TG 3 meeting another TG 3 or TG 4 without restriction. In the passing places, there is no encounter factor limit, so even two TG 6 vessels may meet there.
Using traffic group assignments, the encounter factors for each canal section, fixed speed limits of 15 km/h (12 km/h for vessels over 8.5 m draft), and continuously received vessel position data from the planning system, controllers can produce an optimal passage plan for each ship before it enters the lock.
Top image: Traffic controller in front of the distance-time diagram
Bottom image: Vessel traffic in the Kiel Canal 74:48:59 WNO SMOKING