Castelion

Castelion was founded in late 2022 by a group of former SpaceX engineers, including Bryon Hargis, Sean Pitt, and Andrew Kreitz, with the goal of building affordable long-range strike systems for the United States and its allies. The company is headquartered in El Segundo, California, with additional operations in Allen and Midland, Texas, and a planned solid rocket motor campus in Sandoval County, New Mexico. Its first major program, Blackbeard, is a ground-launched hypersonic missile aimed at delivering roughly 80 percent of the capability of legacy systems like PrSM Increment 4 at a significantly lower price point. The team conducted its first hypersonic vehicle test in the Mojave Desert in March 2024 and went on to complete more than twenty development flight tests in 2025. Subsystems including solid rocket motors, control actuation, flight computers, seekers, and thermal protection are all manufactured in house. A $350 million Series B closed in late 2025 to fund mass production.