The Boeing C-40 Clipper is a military of the Boeing 737-700C. It is used by the US Air Force and the US Navy. Only 19 versions have been built. The C-40A version is built for the US Navy. It is used to provide logistics support. The C-40A is capable of carrying 121 passengers, cargo, or cargo and passengers. The C-40B is the US Air Force model. It is designed to be an "office in the sky" for senior military and government leaders.