Second Lt. Pascual Eley (right), a fire directions officer serving with 2nd Battalion, 11th Marine Regiment, and a native of Fullerton, Calif., and Sgt. Christopher Martinez, the operations chief with the fire direction center and a native of Orange County, Calif., convert target data into firing commands for the gunline during Exercise Desert Scimitar, a combined-arms, live-fire training exercise here, May 2, 2013. The FDC's job is to take the information given to them by forward observers and compute how wind, air pressure, temperature, humidity and other weather conditions will effect an artillery round while airborne. - Second Lt. Pascual Eley (right), a fire directions officer serving with 2nd Battalion, 11th Marine Regiment, and a native of Fullerton, Calif., and Sgt. Christopher Martinez, the operations chief with the fire direction center and a native of Orange County, Calif., convert target data into firing commands for the gunline during Exercise Desert Scimitar, a combined-arms, live-fire training exercise here, May 2, 2013. The FDC's job is to take the information given to them by forward observers and compute how wind, air pressure, temperature, humidity and other weather conditions will effect an artillery round while airborne.