A SpaceX Falcon 9 rocket launched the United States Air Force's first Global Positioning System III space vehicle (SV) from Space Launch Complex 40 (SLC-40) at Cape Canaveral Air Force Station at 8:51 a.m. on 23 December 2018. Due to mission requirements, SpaceX will not attempt to land Falcon 9's first stage after launch.

From the SpaceX GPS II SV01 press release:

The United States's Global Positioning System delivers positioning, navigation, and timing services supporting vital U.S. and allied operations worldwide, and underpins critical financial, transportation, and agricultural infrastructure that billions of users have come to depend on daily.

The United States Air Force's first GPS III satellite built by Lockheed Martin will augment the current constellation of 31 operational GPS satellites. This newest generation of GPS satellites is designed and built to deliver positioning, navigation, and timing information with three times better accuracy, and up to eight times improved anti-jamming capability. GPS is used by over four billion users and supports critical missions worldwide.

GPS is a National Security Space (NSS) mission, critical to national defense. In April 2016, SpaceX was awarded its first NSS mission, GPS III SV01. SpaceX currently has an additional four GPS III missions on contract, all of which will be launched on Falcon 9.