Castelion, a defense technology startup focused on low-cost hypersonic weapons, has secured a $1 billion Series C funding round that values the company at $13 billion. The round comprises $800 million in equity and a $250 million credit facility, co-led by Andreessen Horowitz, Carlyle, and JPMorgan Chase’s Strategic Investment Group, with participation from additional institutional investors.
The capital will accelerate mass production of Castelion’s flagship system, the Blackbeard hypersonic strike missile. Designed and built in California, Blackbeard progressed from a clean-sheet design to an official U.S. government program of record in under four years — a timeline the company says is virtually unprecedented in traditional defense contracting. The missile is engineered for high-volume manufacturing from the outset, leveraging vertical integration to control quality and reduce unit costs.
A significant portion of the new funding will flow into Project Ranger, a thousand-acre campus in Sandoval County, New Mexico. Billed as the largest dedicated hypersonic missile manufacturing facility in the United States, Project Ranger will house high-volume assembly lines intended to ensure the military can deploy hypersonic capabilities at a fraction of historical costs.
Over the past 18 months, Castelion has won more than $500 million in military contracts. The company says it is transitioning from prototype testing to full-scale production and targets initial field deployment as early as 2027. Beyond Blackbeard, the investment will also support development of longer-range precision weapons and next-generation defensive systems.
Castelion’s approach addresses a persistent bottleneck in defense acquisition: the high upfront cost and slow pace of traditional hardware development. By applying rapid iteration and manufacturing-first design — methods more common in Silicon Valley than in legacy defense primes — the startup aims to deliver capable strike systems in quantities sufficient to sustain credible deterrence against peer adversaries. The funding round and production scale-up mark a notable shift toward domestic manufacturing capacity tailored for speed and affordability in modern strategic competition.
