1. Northrop Grumman Corporation, One Hornet Way, MS 9L11/W2, El Segundo, CA 90245, USA
2. Institute for Defense Analysis (IDA), Science and Technology Division, 4850 Mark Center Drive, Alexandria, VA 22311, USA
3. Virginia Polytechnic Institute and State University, 340 Whittemore, Blacksburg, VA 24061, USA
4. Lockheed Martin Corporation, M.S. DC3085, Littleton, CO 80127, USA