Complex 37

The last flight of United Launch Alliance’s Delta 4-Medium rocket lifted off Aug. 22 from Cape Canaveral Air Force Station in Florida, riding more than 1.2 million pounds of thrust from a hydrogen-fueled main engine and two strap-on solid rocket motors.

The last Delta 4 launcher to fly in a single-core configuration rumbled into space Thursday morning from Cape Canaveral with a GPS navigation satellite, leaving United Launch Alliance with five more Delta 4-Heavy missions on contract through late 2023 before the Delta rocket family retires from service.

The last Delta 4-Medium rocket lifted off from Cape Canaveral Thursday with a GPS navigation satellite for the U.S. Air Force.

United Launch Alliance is set to retire part of its rocket family Thursday with the final flight of the Delta 4 rocket’s “single stick” configuration, a mission set for liftoff from Cape Canaveral carrying a new GPS navigation satellite into orbit for the U.S. Air Force.

Weather forecasters expect a 70 percent chance of favorable conditions at Cape Canaveral for liftoff of a United Launch Alliance Delta 4 rocket Thursday with a GPS navigation satellite, marking the last flight of the Delta 4’s single-core variant after 29 flights since 2002.