The presence of three Chinese research vessels in the Indian Ocean has drawn heightened attention from India’s maritime surveillance agencies. The deployment includes Shi Yan-6, Shen Hai Yi Hao, and Lan Hai, all currently engaged in scientific or oceanographic missions that carry potential dual-use implications.

This development reflects China’s growing interest in mapping and monitoring the Indian Ocean, a region central to India’s strategic and economic security.

Shi Yan-6, identified as China’s first geophysical ocean research vessel, is en route to Mauritius. Officially, its mission involves marine geological and geophysical surveys, but Indian observers view it as part of Beijing’s broader maritime domain awareness (MDA) effort.

Image Courtesy: Damien Symon - @detresfa

The vessel is equipped with advanced sub-bottom profilers, magnetometers, and multibeam echo sounders, which can generate detailed seabed profiles—vital for both resource exploration and submarine navigation.

Shen Hai Yi Hao, another Chinese research platform, entered the Indian Ocean in early November 2025. Commissioned in 2019, it supports the Jiaolong manned submersible, which can reach depths exceeding 7,000 metres. Nominally bound for Male, Maldives, its operations include deep-sea sample collection and topographic mapping. Given its capabilities, defence analysts suggest that such vessels could also assist in surveying undersea features vital for submarine operations or cable-laying routes.

Lan Hai, the third vessel, is already conducting survey operations in the eastern reaches of the Indian Ocean. Although framed as a scientific expedition, Indian maritime watchers suspect coordination among these vessels to map key underwater features stretching from the Bay of Bengal to the Arabian Sea.

This activity aligns with recent patterns where Chinese research ships have operated near critical sea lanes and island territories across the Indo-Pacific.

India has intensified its satellite and naval monitoring of foreign research vessels operating near its maritime boundary and Exclusive Economic Zone (EEZ). The Ministry of Defence and the Indian Navy’s Information Management and Analysis Centre (IMAC) are reportedly tracking all three ships. Such deployments typically prompt diplomatic caution and potential denial of port calls at Indian facilities, as seen in earlier instances involving similar Chinese missions.

The timing of the Chinese surveys has gained additional significance following the unexpected cancellation of a NOTAM (Notice to Airmen) related to a BrahMos missile test near the Andaman and Nicobar Islands. While officials have not linked the two events, the sequence underscores India’s sensitivity to foreign hydrographic activities that could inform future military or strategic interests.

China has maintained that its oceanographic research serves peaceful and scientific objectives. However, analysts view these missions as part of Beijing’s long-term plan to refine undersea situational awareness, especially in regions critical for the People’s Liberation Army Navy (PLAN).

The Indian Ocean, a maritime theatre historically dominated by the Indian Navy, is increasingly witnessing Chinese scientific cruises that blur the line between civilian research and naval reconnaissance.

With three Chinese vessels operating simultaneously, Indian defence planners are expected to enhance maritime domain monitoring and potentially coordinate with friendly navies for regional surveillance. The latest deployment illustrates how oceanographic research has emerged as a strategic frontier—one where data and mapping capability can translate directly into tactical and military advantage.

IDN (With Agency Inputs)