Page 3 - Spec Tech Vol 1 Issue 04

Delta IV Heavy rocket's final West Coast

launch

(Image Credit: United Launch Alliance (ULA))
The mighty United Launch Alliance (ULA) Delta IV Heavy rocket launched from Vandenberg
Space Force Base in California for the final time on Saturday (Sept. 24). The mission, known
as NROL-91, blasted off at 6:25 p.m. EDT (2225 GMT; 3:25 p.m. local time) from Vandenberg's
Space Launch Complex-6.

The Delta IV Heavy's final West Coast launch saw the rocket place a classified satellite into an
unknown orbit on behalf of the U.S. National Reconnaissance Office (NRO), an agency within the
Department of Defense tasked with operating spy satellites and disseminating the intelligence
they gather throughout the U.S. military and intelligence communities.

The 217-foot-tall (66.2 meters) ULA Delta IV Heavy has been in service since its first flight in
2004. The rocket was built by McDonnell-Douglas (which was later acquired by Boeing) and can
launch to geosynchronous transfer orbit payloads weighing between 11,060 and 15,470 pounds
(5,020 and 7,020 kilograms).

Most of the rocket's 14 total flights launched classified payloads for the NRO, but NASA has also
used the Delta IV Heavy to boost scientific missions into space. The space agency's Parker Solar
Probe was launched atop the rocket in 2018, while the Artemis program's Orion crew capsule
took its first test flight in 2014 after being launched from a Delta IV Heavy.
ULA has a new massive rocket on the horizon to replace the Delta IV Heavy, called the Vulcan
Centaur. The company hopes the behemoth will make its first flight later this year with a mission
that will see the ashes of late "Star Trek" creator Gene Roddenberry and "Trek" actors Majel
Barrett Roddenberry and James "Scotty" Doohan launched into space.

The ULA Delta IV Heavy will launch two more missions, both of which are likewise on behalf of
the NRO, from Florida's Space Coast. Those two launches will occur in 2023 and 2024,
respectively, if all goes according to plan.

Space Explorer 2022 3