High Quality Content by WIKIPEDIA articles! Horizon Air, a regional airline based in SeaTac, Washington, serves 47 different destinations in the western United States, Canada and Mexico. Horizon Air`s inaugural destinations in 1981 were Pasco, Seattle, and Yakima, Washington which were served with two wet leased Fairchild F-27 turboprop aircraft. In 1982, Horizon Air expanded into Oregon with a purchase of Air Oregon, and added service to seven new destinations. One year later, Horizon acquired Transwestern Airlines of Utah and then expanded into the intermountain West region of the United States. Five of the seven routes introduced with the acquisition of Air Oregon are still served by Horizon, with the exceptions of North Bend/Coos Bay, Oregon and by December 2008, Pendleton, Oregon. In 2008, Horizon restructured existing routes in order to transition to an all Bombardier Q400 fleet, removing the smaller Q200 turboprops as well as the CRJ 700 regional jets from the fleet.