HDCSO USR Vehicles The Homeland Defense Civil Support Office has a requirement to acquire consumable Urban Search and Rescue (USR) vehicles, trailers, and buses to execute Urban Search Rescue (USR) ve... HDCSO USR Vehicles The Homeland Defense Civil Support Office has a requirement to acquire consumable Urban Search and Rescue (USR) vehicles, trailers, and buses to execute Urban Search Rescue (USR) vehicle rescue extraction training. This training is a command-directed requirement established to support two officially approved TRADOC (Training and Doctrine Command) Course Administrative Data documents.