November 6, 2007 Lockheed Martin’s Guided Multiple Launch Rocket System (GMLRS) has achieved all its test objectives in Unitary rocket Phase II product qualification test flights at White Sands Missile Range. The tests verified the missile’s ability to perform in a GPS jamming environment at long range – an essential feature for air strikes in close proximity to friendly troops, or with a low collateral damage threshold.
The GPS jamming did not affect the missile, or the functionality of the warhead’s Point Detonating fuse. The tests also revealed the effects of the unitary warhead on the target post-detonation, and demonstrated the compatibility of "Follow-On" configuration hardware and software with the program’s requirements.
The first rocket tested employed the GMLRS “vertical trajectory shaping” software, allowing it to impact the target vertically, while the second missile used the “nominal trajectory shaping” software, which resulted in a standard ballistic trajectory flight pattern.
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