Signal flag Zulu

Four triangles: black, yellow, blue, red.

Also known as: Zulu flag, Code flag Zulu

Sometimes confused with: Z pennant

Maps & navigationSafety & hazardStandard profile

Meanings

The International Code of Signals flag for the letter Zulu, whose single-flag meaning is: I require a tug.

Officially standardisedVerified fact
Flown alone, signals: I require a tug.
Contexts: Public information, Navigation
Officially standardisedVerified fact
Among vessels engaged in fishing in sight of one another, the same flag signals instead: I am shooting nets.
Contexts: Public information, Navigation

A rectangular flag divided into four triangles meeting at the centre, yellow at the hoist, blue at the fly, black above and red below.

IdentityHigh confidence: High confidence because the identity is defined by a current official standard.
Historical originModerate confidence: Moderate confidence because the historical origin is documented in encyclopedic references, but early or supporting evidence is limited, but the regional or cultural match to this specific claim is not precise.
Current useHigh confidence: High confidence because the current use is defined by a current official standard.
Visual matchHigh confidence: High confidence because the visual match is documented in encyclopedic references.

IMO Resolution A.1116(30), Escape route signs and equipment location markings
International Maritime Organization · retrieved 2026-08-22
The resolution text is not reproduced here and has NOT BEEN READ in full. Registered so records can state that a life-saving appliance marking is defined by the IMO rather than by convention, and which broad class it belongs to. See docs/paywalled-standards.md.
ITU Radio Regulations and the maritime signalling appendices
International Telecommunication Union · retrieved 2026-08-27
Cited for the identity of maritime and radio signalling conventions defined by the ITU. Not cited for national licensing arrangements.

Last reviewed 2026-08-27

Meanings

The International Code of Signals flag for the letter Zulu, whose single-flag meaning is: I require a tug.

Officially standardisedVerified fact

Flown alone, signals: I require a tug.

Officially standardisedVerified fact

Among vessels engaged in fishing in sight of one another, the same flag signals instead: I am shooting nets.

Confidence

IdentityHigh confidence: High confidence because the identity is defined by a current official standard.
Historical originModerate confidence: Moderate confidence because the historical origin is documented in encyclopedic references, but early or supporting evidence is limited, but the regional or cultural match to this specific claim is not precise.
Current useHigh confidence: High confidence because the current use is defined by a current official standard.
Visual matchHigh confidence: High confidence because the visual match is documented in encyclopedic references.

Sources

IMO Resolution A.1116(30), Escape route signs and equipment location markings
International Maritime Organization · retrieved 2026-08-22
The resolution text is not reproduced here and has NOT BEEN READ in full. Registered so records can state that a life-saving appliance marking is defined by the IMO rather than by convention, and which broad class it belongs to. See docs/paywalled-standards.md.
ITU Radio Regulations and the maritime signalling appendices
International Telecommunication Union · retrieved 2026-08-27
Cited for the identity of maritime and radio signalling conventions defined by the ITU. Not cited for national licensing arrangements.

Last reviewed 2026-08-27