DARPA's New Missile Goes To Next Stage
Posted by Bill Sweetman at 11/12/2010 8:19 AM CST
On the surface, LRASM does not look like a DARPA program. It may not involve radical airframe and propulsion technology (the air-launched version may be a modified JASSM) and it is a mainstream mission. However, what makes LRASM “DARPA-hard” – the catchphrase for a challenge on the verge of impossibility – may reside in the guidance and navigation system.
The LRASM-B will be sized for a vertical launch. Contract language suggests that it will have a ramjet sustainer from Pratt & Whitney, based on “residual” assets from an unidentified program. (Here is a fascinating history of Navy ramjet missiles.)
The Navy has been talking, in the air-sea battle context, about a “net-enabled” ASuW (anti-surface warfare) weapon that would take targeting cues from P-8As or MQ-4C UAVs. LRASM is apparently fundamentally different in that it is designed to be autonomous, and to acquire, classify and hit warships at their most vulnerable points without outside assistance, while evading defenses. The idea is to operate in an environment where networks and GPS are denied by enemy jamming and where hostile ships may be taking cover among commercial traffic.
The result is that the LRASM demonstrators will be pushing the state of the art in GPS-denied navigation (using high-accuracy inertial systems and, possibly, astro-tracking), sensors, sensor fusion and automatic target recognition.