Rear Adm. John Elnitsky assumed command Friday of the Naval Undersea Warfare Center, which conducts research and development for submarines and other underwater vessels and weapons. Elnitsky, a native of Whitehall, Pa., graduated from the U.S. Naval Academy in 1980, and obtained advanced degrees in engineering from Naval Post Graduate School. Elnitsky was to assume command of the center during an outdoor ceremony. The guest speaker was Vice Adm. Paul Sullivan, commander of Naval Sea Systems Command. The NUWC has been without a permanent commander since the departure in May of Adm. Stephen Johnson, who held the position for two years. Elnitsky had been the commanding officer of the ballistic-missile submarine Maine from 1998 to 2001.