Kelluu

Kelluu Oy was founded in 2018 and is headquartered in Joensuu in eastern Finland, where it builds and operates its own fleet of unmanned airships. The hydrogen-powered airships are about 12 metres long, fly autonomously at low altitude for about 12 hours and carry sensor payloads of up to 6 kg, such as electro-optical and infrared cameras and passive sensors for electromagnetic emissions.

The company offers its airships for persistent situational awareness in defence and for civil tasks such as wildfire detection and infrastructure monitoring. In 2025 Kelluu took part in Finland's Atlantic Trident and in NATO's REPMUS and Dynamic Messenger exercises, where NATO assessed the airship for maritime surveillance; it has completed two phases of NATO's DIANA accelerator.

Besides electro-optical and infrared cameras, Kelluu lists hyperspectral, radar, RF and communications payloads for its airships, and electronic support measures and magnetic anomaly detection sensors have been flown in exercises. The company states that its airships navigate in GNSS-denied or jammed environments and are proven in Arctic conditions down to –30 °C. In December 2025 it received an award from NATO Allied Land Command at a technical demonstration for the Eastern Flank Deterrence Line in Finland, after multi-day autonomous flights in severe icing, and it is preparing to join experimentation under NATO’s Layered Counter-UAS Initiative as part of a layered counter-UAS and ISR architecture. In 2026 Kelluu reached the final phase of the US Defense Innovation Unit’s Project G.I. with Arctic test events in Alaska, and at a defence technology event in Lapland it carried a 5G small-cell base station with satellite backhaul to provide airborne 5G coverage on the 3.5 GHz band.

In April 2026 Kelluu raised 15 million euros in a Series A round led by the NATO Innovation Fund, its first investment in a Finnish company.