Japan's 'ninja tech' UNICORN masts to give India's warships greater stealth capability

Japan's cutting-edge UNICORN mast technology — part of a suite of systems informally dubbed 'ninja tech' for its stealth properties — is set to be extended to India's warships, marking a significant leap in bilateral defence technology sharing. The UNICORN system consolidates multiple sensors, antennas and electronic warfare components into a single integrated mast, sharply reducing the radar cross-section and electromagnetic emissions that make modern warships detectable.

Traditional warships bristle with separate antenna arrays and sensor housings that scatter radar returns and generate distinctive electromagnetic signatures. UNICORN's unified architecture addresses this by shrinking and combining all these elements, making vessels substantially harder to detect, track and target at sea. Japanese destroyers have pioneered the approach and it has drawn considerable attention from partner navies.

The offer to India comes in the context of the broader India-Japan defence and technology partnership, which has deepened steadily over the past decade through joint exercises, defence equipment agreements and now the AI and technology pacts signed during the Modi-Takaichi talks. The Indian Navy has been modernising aggressively, and stealth-enhancing technology for surface combatants fits squarely into that programme.

For Japan, sharing a sophisticated naval technology with India serves its own strategic calculus in the Indo-Pacific, where both countries share concerns about Chinese maritime assertiveness. The partnership effectively extends the reach of their aligned interests across the Indian Ocean region.

If the UNICORN mast integration moves forward, it would represent one of the most substantive Japanese defence technology transfers to India to date — and a strong signal of the trust embedded in the bilateral relationship.