WASHINGTON — United Launch Alliance launched a classified National Reconnaissance Office spy satellite on a Delta 4 Heavy rocket June 22 at 5:18 a.m. Eastern from Space Launch Complex-37 (SLC-37) at Cape Canaveral Space Force Station, Florida.

It was ULA’s second attempt of this launch that had been previously scheduled for June 21 but was delayed, the company said, “due to an issue with a ground systems pneumatic valve.”

About four minutes into flight, the outer boosters of the three-core Delta 4 Heavy separated. The second stage separated about two minutes later.

At the request of the NRO, ULA ended the webcast nearly seven minutes into the flight after the nose fairing was jettisoned. 

NROL-68 is the Delta 4 Heavy’s 15th and penultimate launch before its expected retirement. The vehicle in 2022 flew its final mission from the West Coast. 

Credit: ULA

This mission was ULA’s first launch of 2023. The company in May 2019 received a U.S. Air Force contract to launch NROL-68. The Delta 4 Heavy configuration first launched in December 2004.

Each of the Delta 4 Heavy’s common booster cores is powered by Aerojet Rocketdyone’s RS-68A main engines. The Delta cryogenic second stage is powered by an RL10C-2-1 engine. The rocket uses liquid hydrogen and liquid oxygen in all stages.

“We had another successful launch for the NRO today,” Maj. Gen. Stephen Purdy, the Space Force’s program executive officer for assured access to space, said in a statement confirming the launch was successful. “The payload we’ve put into space today adds to the unique capability the NRO provides to keep us safe and out in front of the pacing challenges posed by our nation’s competitors.”

ULA is under contract to launch one more NRO satellite on the Delta 4 Heavy in 2024 from Cape Canaveral. ULA then plans to retire the Delta 4 Heavy and replace it with the new Vulcan Centaur rocket.

Lt. Col. Scott Carstetter, Atlas 5 and Delta 4 materiel leader at the Space Systems Command, noted that NROL-68 will be the first of four missions for ULA’s Atlas 5 and Delta 4 in the final year of Atlas/Delta operations.

Sandra Erwin writes about military space programs, policy, technology and the industry that supports this sector. She has covered the military, the Pentagon, Congress and the defense industry for nearly two decades as editor of NDIA’s National Defense...