Flag seen on China’s new aircraft carrier is used for communication

The false claim surfaced after China conducted maiden sea trials of the Fujian, its third and largest aircraft carrier, on May 1, 2024. The tests were a key next step in a vast naval build-up by Beijing as it carves out a more assertive role for itself in the Pacific and beyond.

But decades of animosity between China and Japan — driven by its previous occupation of China and current territorial disputes — often spurs the spread of misinformation on Chinese social media.

Similar false claims misidentifying the flag seen on the vessel were shared elsewhere on Weibo and on X here and here.

In fact, the flag seen on the ship is used for signalling and communication at sea.

Signalling flag

A Google keyword search found a video report by Chinese state broadcaster CCTV on May 1, 2024, with the headline “Navy’s Fujian leaves for the first set of sea trials” (archived link).

The image used in the false posts corresponds to the CCTV report’s 25-second mark, where a triangular flag with a red disk in the centre can be seen flying next to China’s national flag.

Below is a screenshot comparison of the image in the false posts (left) and the CCTV footage (right):

Further keyword searches on Google led to the International Code of Signals for visual, sound and radio communications guide released by the US National Geospatial-Intelligence Agency, which is a method of communication used in seafaring to convey messages about navigation safety and related matters (archived link).

The triangular flag with a red circle corresponds to the number “1” in this system. Meanwhile, the white flag with a red cross corresponds to the number “8” and the flag with diagonal red and yellow lines corresponds to the letter “Y”, as seen in the screenshot below:

By contrast, Japan’s national flag “the rising sun” is usually rectangular with a height to width ratio of 2:3, according to the Japanese government (archived link).

In a Weibo post on May 2, the ship’s manufacturer China State Shipbuilding Corporation rebuffed the claim, writing: “These are signalling flags hung in accordance with the International Code of Signals, it has nothing to do with the ‘sun’ flag.”

A group of signalling flags is usually made up of three alphabet or number flags, and the “sun” flag was actually the signal flag for the number “1”, the post states.