On December 4th, Northrop Grumman announced the successful testing of a solid rocket motor, SMASH!22, as part of their ongoing internal program focused on improving solid rocket propulsion technologies. The static-fire test occurred at the company's facility in Promontory, Utah.
The SMASH!22 motor, measuring 22 inches (56 centimeters) in diameter, fired for approximately 30 seconds. This motor is part of what Northrop Grumman calls Solid Motor Adaptable, Scalable, Half Time/Cost configuration. Its development aimed to assess new manufacturing techniques and materials designed to reduce production time and cost for both missile and space applications.
The development of SMASH!22 falls under Northrop Grumman's Solid Motor Annual Rocket Technology Demonstrator, or SMART Demo, program. This initiative seeks to conduct annual tests of innovative solid motor technologies. Launched in 2023, the company held another test in August.
According to Jim Kalberer, vice president of propulsion systems at Northrop Grumman, the SMART Demo program involves “taking on more technical risk” compared to typical development programs. He explained during a briefing before the test that, “We bring on new materials from new suppliers, things that are not typically part of or have not historically been part of proven rocket motor development, and we do that so we can find new ways to move with speed.”
For this test, Northrop Grumman achieved a critical design review within eight months from a clean sheet. Kalberer noted that, “Typically, a solid rocket motor design and test effort would take three years” to achieve similar progress.
The program has already yielded benefits, including a low-cost propellant developed from a prior SMART Demo test. Kalberer stated, “We have identified places where that will be inserted into existing products, but it also positions us to offer affordable solutions.”
The SMART Demo program has also assessed a new robotic method for motor development. “We spray a liner inside the rocket motor. In the past that has been a hand operation,” said Kalberer. “These robotic processes allow us to more quickly and efficiently remove touch labor and apply liners to the inside of the case.”
The SMASH!22 motor utilized a steel case fabricated using new welding and manufacturing processes, as well as 3D-printed components. It also incorporated the previously demonstrated low-cost propellant.
Kalberer clarified that the motor's size is comparable to those used on interceptor missiles and sounding rockets, but there are no current plans to integrate it into any specific Northrop Grumman products. “What we do is work with our customers to understand emerging requirements and then demonstrate a flight-relevant size that we believe could meet those requirements, so it may have more than one application as the technology moves forward.”
Northrop Grumman also revealed the development of a second motor under this phase of the SMART Demo program: the 29-inch Bombardment Attack Missile Motor, BAMM!29 2.0. A test firing for this motor is scheduled for early 2026.