Vandenberg’s final Delta IV Heavy rocket launch to take place at end of September

VANDENBERG, Calif. – A National Reconnaissance Office mission (NROL-91) aboard a United Launch Alliance Delta IV Heavy rocket is set to take off from Vandenberg Space Force Base on the afternoon of Sept. 24.

"NROL-91 is the latest national security payload to deliver critical intelligence information from space that U.S. warfighters and decision makers need," Space Force Base officials said, adding that NRO capabilities provide the foundation for America's advantage and strength in space.

The Delta IV Heavy rocket – a heavy-lift launch vehicle –is the largest type of the Delta IV family and one of the world's most powerful rockets, officials said. It has had 13 successful launches and is the world's second-highest payload weight capacity rocket in operation.

The launch window for the Sept. 24 launch from Vandenberg's Space Launch Complex-6 opens at 1:50 p.m. Col. Bryan Titus will be the launch decision authority.

It will be the 10th Delta IV launch from Vandenberg, and the fifth and final heavy variant from Vandenberg Space Force Base.