Lockheed Martin says PrSM Increment 4 clears propulsion milestone on path to flight tests

Lockheed Martin said on June 3 that its Precision Strike Missile Increment 4 offering reached a pivotal propulsion milestone in a recent Direct Connect Transition Test conducted with L3Harris and the U.S. Army. The company said the development missile cleanly transferred from booster to ramjet inside L3Harris’ high-speed-air-breathing propulsion facility, a step it described as a major risk-reduction event before flight testing.

The test matters because Lockheed Martin said it removes the primary technical barrier to flight-testing the PrSM Inc. 4 design. The company said flight testing is expected to begin in the fall of 2026, keeping the program on a path toward operational fielding, though that timing is still a company projection rather than a completed program milestone.

PrSM is already a core part of Lockheed Martin’s Army missile lineup, and the company describes the baseline weapon as a next-generation long-range precision-strike system built for the U.S. Army. On the company’s product materials, the current missile is described as delivering 499+ kilometers of range and remaining compatible with HIMARS and M270 launchers.

Increment 4 is meant to push that envelope further. Lockheed Martin said the ramjet-powered architecture would give the missile more than 1,000 kilometers of standoff distance, while still fitting the Army’s existing launch platforms and logistics flow. That compatibility is central to the pitch: more reach without forcing the service to buy a new launcher fleet.

The company also framed the ground test as evidence that the propulsion concept has matured beyond the lab. In a companion L3Harris release, the partner company said the test confirmed the transition from the rocket booster to the ramjet engine, and Lockheed Martin’s Randy Crites said the result shortens the path to warfighter delivery.

This milestone lands against a broader production push. In March, Lockheed Martin announced a framework agreement with the Department of War to accelerate PrSM production, saying the arrangement would quadruple capacity; in April, management said munitions commitments for Patriot, THAAD and PrSM would support investments to raise production rates to three to four times current levels.

That industrial buildout is not just about one missile. Lockheed Martin has been signaling for months that munitions demand is rising and that it plans to spend heavily on manufacturing infrastructure, supply chain resilience and workforce expansion. The company’s first-quarter results also showed PrSM among the tactical and strike missile programs contributing to production ramp-up costs.

The timing also fits the Army’s broader long-range fires modernization effort. PrSM Increment 2 completed its first flight test in March, and Lockheed Martin has been positioning the program as a family of munitions that can evolve from baseline strike to maritime and extended-range missions while staying inside existing launcher architecture.

For investors and defense buyers, the near-term question is execution rather than concept. The next checkpoints are the fall flight tests, any follow-on Army decision-making and whether Lockheed Martin and its suppliers can keep pace with the company’s stated production goals while moving a more complex ramjet design toward fielding.