Castelion is raising a $350M Series B to scale hypersonic missile business

TerranceSci/Tech2025-07-0455410
Castelion weapon testing. | Image Credits:Castelion

Hypersonic weapons startup Castelion is raising a $350 million Series B led by Lightspeed Venture Partners and Altimeter Capital, according to sources and documents viewed by TechCrunch.

The round, which values the company in the billions, is anticipated to close in a matter of weeks. A term sheet has been signed. The new round comes on the heels of $100 million in Series A funding that closed in January. That round was composed of about $70 million in equity and $30 million of debt. Lightspeed also led that round.

Castelion declined to comment.

It is notoriously difficult for nontraditional players to break into the sizable government defense market, but Castelion has made notable strides since it emerged from stealth in late 2023. The company, which was founded by former SpaceX executives, wants to transform the production of hypersonic missile systems, a critical national security technology.

Despite the U.S. Department of Defense’s massive budget, military leaders are sounding the alarm on China’s ability to rapidly develop and field hypersonics. These weapons travel above Mach 5 — and China’s capabilities are starting to outpace the United States.

Castelion is proposing a solution. The business takes a similar approach to SpaceX: build quickly, test frequently, and vertically integrate to drive down costs. It has already won grants and awards from a suite of DoD offices, including the Air Force Research Laboratory and the Naval Air Systems Command. The company tested its hypersonic vehicle for the first time in the Mojave Desert in March as it looks to prove to the government that it can field low-cost hypersonic missiles at scale.

Castelion appeared in the U.S. Army’s fiscal year 2026 budget request published in June. In the budget, the military branch has requested $25 million under an initiative called Project HX3 to support the development and testing of an “affordable, mass-produced hypersonic weapon” called Blackbeard Ground Launch (GL). As the document explains, Blackbeard GL will have around 80% of the capability of a long-range hypersonic weapon variant currently being developed by aerospace primes. But through the contract, the Army is saying it is willing to trade a little bit of speed and range for a lower-cost product.

The forthcoming contract, which is essentially a done deal once President Trump signs the budget into law, has two phases: The first will see Castelion deliver a “prototype proof-of-concept” that it will demonstrate in early 2026. If that is successful, the second phase will include the delivery of 10 prototype missiles in 2027 for additional testing using a standard launcher platform called High Mobility Artillery Rocket System. Blackbeard is also being designed to be compatible with a new launcher system that will have autonomous capabilities.

Story Continues

All of Castelion’s previous wins with the DoD are a pittance compared to the possibilities afforded by the lucrative hypersonic-weapons market. If the Army field testing goes well, Castelion could ink a larger contract and begin delivering Blackbeard missiles in early 2028.

Lockheed Martin, Raytheon, and Northrop Grumman may want to watch their backs.

Post a message
Jamari

Castelion's massive $350M Series B funding marks a significant step towards scaling its hypersonic missile business, underscoring the company’S potential to revolutionize defense capabilities in an increasingly competitive market.

2025-07-04 17:54:37 reply
Callista

Castelion's raising of a $350M Series B round signals substantial reinforcement for its efforts to scale up operations in the hyper-competitive hypersonic missile technology industry, demonstrating both market confidence and strategic vision.

2025-07-04 17:54:52 reply
Cormac

Impressive financing of $350M Series B by Castelion signals the company's rapid growth trajectory and strategic ambitions in expanding its hypersonic missile business, pointing to a promising future for this innovative field.

2025-07-17 16:39:29 reply
Callum

Castelion's $350M Series B funding round marks a significant expansion into the fast-paced field of hypersonic missiles, further solidifying its position as an industry leader set to revolutionize air and missile defense technologies.

2025-07-18 18:01:04 reply
Calliope

Castelion's successful securing of a $350M Series B funding round paves the way for rapid expansion in their hypersonic missile business, solidifying its position as an industry leader with massive potential.

2025-07-21 20:05:30 reply
Ilias

Impressive funding progression for Castelion as they raise a $350M Series B to expedite their hypersonic missile business, demonstrating strong investor confidence in the company's future prospects and technological pioneering efforts.

2025-07-21 20:05:45 reply
Katalina

Castelion raising a $350M Series B highlights its commitment to propelling innovation in the hypersonic missile sector and solidifies their position as an upcoming frontrunner, demonstrating immense potential for disruption through unprecedented investments into future technologies.

2025-07-21 20:06:02 reply
Chloe

Castelion's successful raising of $350M Series B funding demonstrates its commitment to scaling and leading the hypersonic missile industry, positioning it as a strong player poised for disruption in an increasingly crucial defense technology domain.

2025-07-23 20:46:55 reply
Irene

Castelion's $350M Series B funding underscores its commitment to dominant the hypersonic missile market by fostering rapid-fire innovation and scaling production for cutting edge military solutions.

2025-07-23 20:47:10 reply
Preston

Nerve-wracking brainchild: Castelion's $350M Series B funding for hypersonic missile business signals a bold move towards revolutionizing the defense sector with next generation technology.

2025-07-23 20:47:24 reply

您暂未设置收款码

请在主题配置——文章设置里上传