The U.S. Air Force is augmenting it's C-22B transport fleet with C-40Bs. The C-22B is a militarized commercial Boeing 737s. But the C-40B is based on a recent, and more capable, B-737. The C-22B has a range of 3,600 kilometers, while the C-40B goes up to 9,000 kilometers per flight. The C-40B's basic configuration is for 26 passengers and 11 crew, but can be configured for up to 60 passengers. The Air National Guard is a major user of the C-22B and C-40B. Both aircraft are used for rapidly moving personnel. When specialist personnel (technicians or emergency response teams) are needed somewhere in a hurry, the C-22B and C-40B are used. The new aircraft can deliver these personnel overseas, while the C-22B was largely confined to use in the United States (or Europe or the Pacific, depending on where the aircraft was based.) The C-40B also has better communications, including in-flight access to the Internet. The air force plans to buy as many as six C-40Bs. They have 14 C-22s, but most of them are in storage.
