What Are Day Shapes?
Black balls and cones hoisted on the mast - the international daytime language for saying 'what I'm doing', and the small rule most often forgotten.
Day shapes are black geometric shapes used by vessels to show their status by day. They are the daytime equivalent of lights and are hoisted on the mast. They are often overlooked on small craft, but are expected in busy waters and during inspections.
The table below sets out the basic signals.
Day shapes
Signal | Meaning |
|---|---|
One ball | I am at anchor |
Cone point down | I look like a sailing vessel, but my engine is running too |
Two balls, one above the other | I am not under command |
Ball-cone-ball | My ability to manoeuvre is restricted |
In practice, it comes down to two signals: the anchor ball (the daytime declaration of a vessel at anchor in a bay, proof of status under the collision regulations and in any damage dispute) and the motor cone (a vessel with sails up but engine running is motor-driven for right-of-way purposes; a “sailing vessel” without the cone puts everyone else’s judgment off).
Fold-up plastic sets are cheap, compact and once bought will last for years. The signals are for daytime use; in the dark, the lights take over (at anchor: 360-degree white).