By Mauro Orru

Quantum Systems said it had raised $1.2 billion at a valuation of roughly $8 billion, bringing in fresh capital to expand drone production and invest in software for autonomous systems powered by artificial intelligence.

The startup said European aircraft maker Airbus, asset manager Blackstone, private-equity firm Advent and equity investor Noteus Partners co-led the financing round, which also attracted interest from technology investment firm BOND, financial services firm Fidelity Investments, asset manager Wellington Management, investment firm A.P. Moller Holding, venture-capital firm Elephant Lake Ventures and existing shareholders like Balderton and HV Capital.

"We are profitable, deployed around the world and with the latest financing round we now have more than $1.2 billion of dry powder to execute," Florian Seibel, co-founder and co-chief executive, said.

The startup said the financing round had more than doubled its valuation, underscoring investor appetite for a company in the burgeoning defense sector after Russia's invasion of Ukraine sparked a wave of investments from governments of the North Atlantic Treaty Organization to replenish their stockpiles of weapons and be better positioned to fend off potential threats.

Quantum Systems makes multisensor unmanned aerial systems that can assist government agencies and commercial clients with aerial data intelligence. The company also offers unmanned ground vehicles for land missions and is working on a unmanned surface and underwater platforms for marine operations, according to its website. Its systems executed over 19,000 missions in Ukraine last year, it said.

Quantum Systems is seeking to expand production and ramp up investments in software and AI capabilities. Its production footprint spans Germany, Ukraine, the U.S., Australia, Romania, the U.K. and the Baltics.

"The future is unmanned. Defense will be defined by autonomous systems that can operate together across domains in real time," Seibel said.

Write to Mauro Orru at mauro.orru@wsj.com