Alaska's Bush hubs were well served by Boeing 737-200 combi aircraft operated by Alaska Airlines. The planes could be configured for six pallets or about 90 passengers, or combinations in between. This allowed Alaska Air to deliver freight, especially mail, along with the passengers. The 200s have been replaced by 737-400 aircraft. Normally commercial aircraft in this category are not allowed to carry both people and freight. Senator Ted Stevens was able to get a exception to the regulation for air service in Alaska. This was critical to Dutch Harbor, Dead Horse, Bethel, Kotzebue, Nome, and Barrow.