United Launch Alliance (ULA) is a joint venture of Lockheed Martin Space Systems and Boeing Defense, Space & Security. ULA was formed in December 2006 by combining the teams at these companies which provide spacecraft launch services to the government of the United States. U.S. government launch customers include both the Department of Defense and NASA, as well as other organizations. With ULA, Lockheed and Boeing held a monopoly on military launches for more than a decade, until the US Air Force awarded a GPS satellite contract to SpaceX in 2016. ULA provides launch services using three expendable launch systems – Delta II, Delta IV and Atlas V. The Atlas and Delta launch system families have been used for more than 50 years to carry a variety of payloads including weather, telecommunications and national security satellites, as well as deep space and interplanetary exploration missions in support of scientific research. ULA also provides launch services for non-government satellites: Lockheed Martin retains the rights to market Atlas commercially. Beginning in October 2014, ULA announced that they intended to undertake a substantial restructuring of the company, its products and processes, in the coming years in order to decrease launch costs. ULA is planning on building a new rocket that will be a successor to the Atlas V, using a new rocket engine on the first stage. In April 2015, they unveiled the new vehicle as the Vulcan, with the first flight of a new first stage no earlier than 2019.