L-3 Communications Vertex Aerospace LLC, Madison Miss., has been awarded an $11,094,779 modification (P00043) to exercise option four of the existing contract (FA3002-10-C-0001) for helicopter maintenance. Work will be performed at Kirtland Air Force Base (AFB), N.M., and is expected to be completed by Sept. 30, 2014. Fiscal 2014 operations and maintenance funds will be obligated when they become available. The Air Force Nuclear Weapons Center, Directorate of Contracting, Specialized Branch, Kirtland AFB, N.M., is the contracting activity.