Rule 24 · USCG Navigation Rules
Barge pushed ahead or towed alongside
A barge pushed ahead shows sidelights at its forward end; towed alongside she adds a sternlight — Inland adds a special flashing light.
Situation
Viewpoint
Display
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From the port bow you see:
- red — Port sidelight (forward end)
→ Barge pushed ahead or towed alongside — Pushed ahead (not a composite unit), seen from the port bow.
US Inland difference
Inland Rule 24(f): barges pushed ahead or towed alongside ALSO carry a SPECIAL FLASHING LIGHT at the forward end — yellow, flashing 50–70 times per minute, showing over an arc of 180°–225° (Inland Rule 21). It does not exist in the International Rules.
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Memory aid
“Barges up front wear the sidelights. Inland only: plus a yellow special flashing light at the head of the tow.”
What it means
Pushed ahead (not a composite unit)
Sidelights at the forward end only — no sternlight, because the pusher's sternlight covers the aft sector. Any number of barges pushed in a group is lit as one vessel.
Towed alongside
Adds a sternlight to the forward-end sidelights. Fog signal (one prolonged + three short) only if manned.
Day shapes
No special day shape — by day this vessel is recognised by sight, not by shapes.
Light details
Pushed ahead (not a composite unit)
| Light | Colour | Arc | Position |
|---|---|---|---|
| Port sidelight (forward end) | red | 112.5° to port | Port side, deck level |
| Starboard sidelight (forward end) | green | 112.5° to starboard | Starboard side, deck level |
Towed alongside
| Light | Colour | Arc | Position |
|---|---|---|---|
| Port sidelight (forward end) | red | 112.5° to port | Port side, deck level |
| Starboard sidelight (forward end) | green | 112.5° to starboard | Starboard side, deck level |
| Sternlight | white | 135° aft | Stern |
2D profile
Labelled side view — works without WebGL and in print. Variant shown: Pushed ahead (not a composite unit).
In fog, she sounds
Don’t confuse with…
Official source
Rule 24, reproduced from the public-domain COLREGs Rule 24(f) — USCG Navigation Rules. Diagrams and 3D scenes are original to boatrules.com.