Naval Surface Warfare Center, Crane Division (NSWC Crane) Expeditionary Electro-Optic Systems Branch and Electro-Optic Maintenance Branch personnel recently finalized the development of a test station along with test processes and analysis tools to measure the thermal drift of weapon-mounted electro-optic (EO) scopes and sights. The initiative addressed the tendency of a current Special Operations Forces (SOF) weapon sight’s reticle to shift with variations in temperature. The Electro-Optics Team that collaborated to develop this test capability included Ron Volpone, Scot Curry, Matt Thurner and Brandon Clarke.
Clarke, an electro-optics technician with prior experience as an Army Ranger, explained that warfighters are required to fight in environmental conditions ranging from -40 degrees Fahrenheit in the brutal cold of the mountains to 140 degrees Fahrenheit in the heat of the desert. “Providing electro-optics that can not only operate in these temperatures, but provide reliable sighting accuracy across these temperatures without requiring the weapon to be boresighted is an absolute necessity,” he said. “A sight reticle drifting outside of specification due to temperature can be the difference between hitting the target and missing the target.”
In order to ensure SOF personnel can hit the target despite extreme temperatures, engineers from the EO Technology Division worked to modify an existing boresight alignment station currently used to support Air Platform EO systems to make it functional for use with weapon-mounted sights. The test station and software analysis tools required about five weeks to develop initially, since it was important to determine a method to measure the center of the reticle without human input in order to provide consistent measurement of the thermal drift. The thermal drift testing is an ongoing process that continues to be refined and improved, and plans are underway for NSWC Crane to test longer-range optical sights as well as the close-quarter battle sights that are currently being evaluated.
The test capability that now resides within the EO Division to measure and analyze thermal drift of weapon-mounted EO systems is unique in both the Department of Defense (DoD) and industry test communities. NSWC Crane is now highly engaged with industry to provide guidance on the warfare center’s optical sights tests and analyses, and compare the results to vendor products. “Long term, the thermal drift test capability will allow the warfighter to ‘require’ a more consistent product over their mission temperature profile,” Clarke said.
The Expeditionary EO Systems Branch provides engineering, logistics and acquisition support for various DoD entities including optical sight support for the United States Special Operations Command and the U.S. Marine Corps.