The U.S. Navy and Air Force really like the Boeing 737 airliner. The two services are in the process of buying over 150 of them. The B-737 has been used successfully since the 1960s as an airliner. It first flew in 1965, and over 5,000 have been built.
The U.S. Navy C-40A is a modified Boeing 737-700C commercial aircraft. The plane entered service in 2001, and 19 have been built, eleven for the navy. The 78 ton aircraft can carry 121 passengers, or eight cargo pallets (or a combination of both, usually three pallets and 70 passengers.) Max range is 5,600 kilometers. It normally carries a crew of five (two pilots, one crew chief, one loadmaster and one transport safety specialist, which is what the navy calls a flight attendant). When carrying just cargo, the flight attendant does not come along. The air force got four V-40Bs, which are basically executive transports, that can also operate as airborne headquarters. The other six air force aircraft are C-40Cs, which is basically the same as the C-40A. The C-40A is operated by navy reservists, and is mainly used to rush needed parts or personnel to where the fleet needs them. The C-40A replaced the C-137 (a military version of the 148 ton B-707.)
The navy is also using the 737 as the basis for its new P-8 maritime reconnaissance aircraft. The C-40 experience had a lot to do with the P-8 decision. Cruise speed for the 737 is 910 kilometers an hour and the P-8 version has a crew of 10-11 pilots and equipment operators, who operate the search radar and various other sensors. The 737 has hard points on the wings for torpedoes or missiles. The P-8A will be the first 737 designed with a bomb bay and four wing racks for weapons. The P-8 costs about $275 million each. Five are on order, and the first flight is to take place this year. Eventually, over a hundred P-8s are expected to enter service (for the U.S. Navy foreign customers as well.) The navy also plans to order another seven C-40As.