Castelion Announces Series A Funding

On a path to being outgunned

China is actively eroding the combat power advantage of the United States and its allies. Its combined air forces are the largest in the Indo-Pacific. By a simple count of ships, China’s navy is already the largest in the world. With improved missile capabilities, China can project power further from its own shores and could surpass the United States and its allies in total firepower. Each year the ability of the United States and its allies to deter China from using coercion and force to pursue its interests diminishes.

Increasingly undeterred, China routinely contests United States and allied economic and security interests: impinging on freedom of navigation through international waters, challenging territorial sovereignty, and threatening democratic self-determination. To deter aggression and preserve peace, the US and its allies must rebuild their combat power advantage relative to China by preparing to fight and win.

Rebuilding America’s advantage

An affordable, mass-produced hypersonic long-range strike capability is needed to rebuild a decisive combat power advantage. Simply put, the United States and its allies need far larger quantities of long-range strike weapons to hold the large number of military assets China has built-up at risk. Hypersonic speed delivers lethality, survivability, and standoff range. These weapons must also be sufficiently low-cost to enable mass production and widescale fielding. Mass production of larger quantities gives the United States and its allies an advantage in magazine depth and the ability to mass fires. Widescale fielding of low-cost weapons imposes an unfavorable cost-exchange dilemma on China, undermining its build-up of combat power. By holding threat assets at risk through a decisive combat power advantage, the US and its allies can credibly signal to China that the cost of aggression is so high that it is not worth it to even try.

Doing things differently

Castelion is helping America and its allies preserve peace through deterrence by developing mass-producible hypersonic long-range strike weapons. Given the nature of the threat, we need to move fast and do things differently to deliver the needed capabilities on operationally relevant timelines. Existing development and production models will not deliver the needed capabilities in time.

Castelion achieves low-cost and speed to capability by designing for mass production, vertically integrating to control schedule, and using rapid iterative design cycles with modern manufacturing practices. By intentionally avoiding exquisite designs, embracing agile hardware development, and maintaining a focus on cost and manufacturability, we can field capabilities in months instead of decades.

Rapid progress

Castelion used its seed round funding to demonstrate the feasibility of using historic American hardware development approaches in a modern context. We designed, built, and flew internally developed solid rocket motors, low-cost missile avionics, and hypersonic thermal protection material for internal development and industry use, successfully executing three internal flight tests in less than a month.

We are under active contracts funded by the US Navy, US Air Force, and US Army and have made rapid progress in the development and test of our first low-cost, mass-producible hypersonic strike weapon.

Now, Castelion is excited to announce a $100M capital raise. This includes a $70M Series A, led by Lightspeed Venture Partners with participation from a16z, Lavrock Ventures, Cantos, First In, BlueYard Capital, and Interlagos, and $30M in Venture Debt financing provided by Silicon Valley Bank, with final close expected in February. With this funding we will further accelerate test cycles, scale our mass production facilities, and execute a capability demonstration of our first hypersonic weapon. These efforts will move us faster and closer to regaining a decisive advantage and thereby creating credible deterrence.