Killeen Regional Airport / Robert Gray Army Airfield — Fort Cavazos, United States

GRK serves Killeen, Texas, through Killeen Regional Airport, also known as Robert Gray Army Airfield, reflecting its dual civilian-military status near Fort Cavazos (formerly Fort Hood). This shared-use facility supports commercial flights for soldiers, families, and contractors connected to one of the US Army's largest installations, alongside continued military aviation operations on the same runways. American Airlines has historically operated regional jet service linking GRK to Dallas-Fort Worth, making it a critical travel point for permanent change of station moves, deployments, and homecoming events tied to the base. The airport's identity shifted somewhat after Fort Hood's 2023 renaming to Fort Cavazos, though the airfield retains its Robert Gray designation honoring a World War II pilot from the local area.