CONCORD, Mass. – Lt. Col. Bradley D. Rennich, new 46th Test Squadron Detachment 1 commander, addresses members of the detachment and invited guests after a transfer of command ceremony at the Old North Bridge here July 15, while Major Gregory A. Grimes, 46th Test Squadron commander, looks on. Rennich replaces Lt. Col. David M. McIllece as commander of the detachment, which is headquartered at the 46 TS at Eglin Air Force Base, Fla. The squadron is the principal Air Force organization for the developmental test of command, control, communications, computers, intelligence, surveillance and reconnaissance, or C4ISR, systems. (U.S. Air Force photo by Linda LaBonte Britt)