WASHINGTON — Anduril Industries won a $19 million contract from the U.S. Navy to develop a 21-inch diameter solid rocket motor for the second stage of the Standard Missile 6 — a surface-to-air naval weapon used to intercept aircraft and ballistic missiles.

Anduril, a defense contractor known for its use of robotics and artificial intelligence in military drones, has set its sights on becoming a major supplier of solid rocket motors to the Pentagon. The company last year acquired the startup Adranos, which invented a fuel called Alitec — a mixture of lithium and aluminum to power solid rocket motors used in tactical missiles and space launch vehicles. 

Solid propellant — a stick of fuel and oxidizer pre-mixed and molded into a specific shape —  powers weapons systems ranging from tactical munitions to nuclear-armed intercontinental ballistic missiles. The ongoing conflicts in Eastern Europe and the Middle East have strained existing production capacity for tactical solid rocket motors, and the Pentagon worries that there are not enough domestic sources.

Currently only Northrop Grumman and L3Harris Technologies supply solid rocket motors to DoD. L3Harris is the current supplier of rocket motors for the Standard Missile 6, made by Raytheon

Under the Navy contract, Anduril will “demonstrate a high-performance, 21-inch diameter second stage rocket motor for an SM-6 variant for potential use in fleet area air defense against advanced, fast-moving threats,” the company said June 12 in a news release. 

The Navy is interested in qualifying a third supplier as it plans to acquire hundreds of SM-6 variants in the coming years, said Neil Thurgood, senior vice president of Anduril. He said the company is currently supplying sub-20-inch diameter rocket motors to several other DoD programs and customers.

Anduril manufactures solid rocket motors in McHenry, Mississippi. The company this week announced it is investing more than $75 million to increase the propellant mixing and solid rocket motor annual production capacity at the facility from 600 to more than 6,000 tactical-scale solid rocket motors.

“The investment will allow Anduril to significantly expand the Mississippi Solid Rocket Motor Complex, a 450-acre propellant mixing and solid rocket motor production facility that has been sited for millions of pounds of explosives,” the company said. Anduril plans to renovate 92,000 square feet of factory space, adding new robotics equipment and manufacturing systems.

L3Harris: no more primes needed

The Pentagon’s push to expand its roster of prime solid rocket motor suppliers is facing some pushback. 

Christopher Kubasik, CEO of L3Harris Technologies, has argued that the Pentagon does not need more prime contractors for solid rocket motors and should focus investments on bolstering the sub-tier vendor base supporting the existing primes.

L3Harris last summer acquired Aerojet Rocketdyne, one of the nation’s two top suppliers of solid rocket motors.  

During a first-quarter earnings call April 26, Kubasik said he expects a rising demand for solid rocket motors. “Over the long-term, between five to seven years, double-digit growth on the top line does not seem unreasonable to me,” he said. “We have to, of course, invest in the capacity.”

He said the bottlenecks experienced in the supply of solid rocket motors are due to shortages in lower-tier items. “We’ve made good progress in that regard, investing in our suppliers, getting additional suppliers. I continue to think the more money the government can give to the supply chain, the better off we are.”

“And I continue to believe we don’t need an additional solid rocket motor prime. What we need is someone working on the igniters, the nozzles, and the cases,” said Kubasik. “We’ve ordered equipment to continue to expand, whether it’s mixers, ovens. They unfortunately tend to have a 50 to 60 week lead time.”

Sandra Erwin writes about military space programs, policy, technology and the industry that supports this sector. She has covered the military, the Pentagon, Congress and the defense industry for nearly two decades as editor of NDIA’s National Defense...