ULA Launches final Vandenburg Delta IV Heavy for NROL-91

Delta IV Heavy being prepared for launch | Credit: ULA

On September 24 at 6:25pm EDT (22:25 UTC), ULA launched the NROL-91 mission for the National Reconnaissance Office on the Delta IV Heavy rocket from Space Launch Complex 6 (SLC-6) at the Vandenburg Space Force Station in Florida. The exact payload details are classified. This was the final Delta IV Heavy launching from California (there are two more Delta IV Heavy missions that will launch from Florida). Delta IV Heavy consists of three Delta IV cores and an upper stage, the DCSS (Delta Cryogenic Second Stage). It had its first flight in 2004. SLC-6 was originally intended for West Coast space shuttle missions but was later modified for West Coast Delta IV launches. This will be the 123rd orbital launch attempt of 2022, 153rd ULA launch, and the 14th Delta IV Heavy mission.