The US Navy has successfully launched a Solid Fuel Integral Rocket Ramjet (SFIRR) from an unmanned target drone.
The work marks a step towards the modernisation of missile technology, says the Naval Air Systems Command (NAVAIR).
The test took place over the Point Mugu Sea Range in California. NAVAIR did not give the exact date of the test and made no mention of the speed the SFIRR attained, how far it flew, and whether or not it hit a target.
NAVAIR used a BQM-34 drone to launch the SFIRR, which had been integrated with the drone’s fire control system.
Based on the known length of the BQM-34 – 6.7m (22ft 11in) – NAVAIR images suggest that the length of the SFIRR is just under 3m, or roughly the same length as the Raytheon AIM-9 Sidewinder air-to-air missile.
Solid-fuel ramjets such as SFIRR offer some benefits over liquid-fuel ramjets.
While liquid-fuel ramjets offer higher efficiency and throttle control, they are more complex and heavier due to fuel delivery systems. Solid-fuel ramjets are simpler, more rugged, and easier to store and deploy, but lack throttle control and burn less efficiently.
“This successful integration validates key aspects of our design and moves us closer to delivering an advanced propulsion system that will provide warfighters with greater range and speed,” says Abbey Horning of NAVAIR’s weapons division.
