Castelion has secured a $350 million Series B round to scale production of its hypersonic weapons, sharpening the United States’ conventional deterrence posture. The Torrance, California based defense technology company says the new capital will allow it to move from prototype programs to sustained industrial output of its flagship system, Blackbeard. The raise comes as the Pentagon treats affordable, mass-produced hypersonic munitions as one of its highest modernization priorities.
Financing to Scale Hypersonic Production
The Series B financing is led by Altimeter Capital and Lightspeed Venture Partners, with participation from Lavrock Ventures, Andreessen Horowitz, General Catalyst, First In, Space VC, Cantos, BlueYard, Avenir, Champion Hill, and Interlagos. Castelion plans to use the funds to complete integration of Blackbeard with U.S. Army and U.S. Navy launch platforms and to support multi-service testing campaigns scheduled for 2026. Chief executive and co-founder Bryon Hargis said Blackbeard is intended to narrow the hypersonic gap with China and Russia and that the funding enables the company to “build fast, test often, and produce at volumes that matter in the real world.”
Manufacturing Build-Out Across the United States
A significant portion of the capital will accelerate Project Ranger, Castelion’s new production and final-assembly hub in Sandoval County, New Mexico. The 1,000-acre solid rocket motor manufacturing campus, announced in November, is designed to produce thousands of Blackbeard missiles per year and sustain hundreds of high-skilled industrial jobs in the region. Combined with existing operations in New Mexico, Texas, and California, the facility is intended to anchor a domestic hypersonic manufacturing network focused on throughput rather than niche volumes.
Investor Confidence in a New Defense Industrial Model
Investors frame the round as a bet on speed, scale, and a new model for the U.S. defense industrial base. Erik Kriessmann, partner at Altimeter Capital, highlighted that a team of SpaceX alumni took a clean-sheet hypersonic concept to more than 25 flight tests and major integration contracts in roughly two and a half years, arguing this justifies scaling from hundreds to thousands of missiles annually. Lightspeed partner Connor Love said Castelion is not only building missiles but also rebuilding America’s industrial depth, pointing to its ability to move from blank-sheet design to hardware under test faster than expected across the sector.
Strategic Importance of Hypersonic Capacity
Several backers tied the investment directly to long-term geopolitical competition. Lavrock Ventures partner Alex Poulin said hypersonic weapons only influence outcomes if they can be produced at scale and praised Castelion for engineering a production-ready capability geared toward real-world deployment rather than demonstrations. Andreessen Horowitz general partner Katherine Boyle argued that hypersonic capacity will shape great power dynamics for decades, noting that China began deploying such systems at scale years ago and positioning Castelion as a core player in a renewed American arsenal, while General Catalyst managing director Paul Kwan said the company is transforming the economics and tempo expected of modern deterrence.
Breaking the Cost and Speed Paradigm
In 2025, Castelion ran more than 20 development flight tests to validate critical subsystems such as internally produced solid rocket motors, control actuation systems, flight computers, seekers, thermal protection materials, and mission software. Each campaign has focused on low-cost, mass-producible architectures in place of bespoke designs that traditionally emerge in small quantities over multi-year schedules at very high cost. By compressing design-to-launch timelines from years to months and building an industrial base aimed at high-rate missile production instead of boutique inventories, the company aims to change how advanced strike weapons are engineered, certified, and fielded.
Castelion describes Blackbeard as the first U.S. hypersonic system designed from day one for industrial-rate output, commercial-grade unit costs, and continuous flight test iteration. With a $350 million Series B, a large coalition of venture and growth investors, and a national manufacturing footprint taking shape around Project Ranger, the company is positioning itself as a primary supplier of affordable hypersonic capacity to the Pentagon. If it delivers on its testing cadence and production targets, Castelion will not only add a new weapon to U.S. inventories but also help redefine expectations for speed, scale, and cost in strategic weapons manufacturing.