CAPE CANAVERAL — United Launch Alliance was able to finally send up its first launch of the year, the penultimate liftoff of its Delta IV Heavy rocket and the last of the Delta family of rockets.
The triple orange flames of the powerhouse rocket lit up the Space Coast sky at 5:18 a.m. Thursday from Cape Canaveral Space Force Station’s Space Launch Complex 37 taking up a classified payload on the NROL-67 mission for the National Reconnaissance Office.
The launch already delayed from the spring faced another delay when an early morning Wednesday attempt encountered a valve issue with the ground systems supporting the rocket, but teams were able to conduct the launch a day later.
Let's relive liftoff of the #DeltaIVHeavy carrying #NROL68 for @NatReconOfc! 🚀🐉 pic.twitter.com/iIJOl2Arar
— ULA (@ulalaunch) June 22, 2023
Various forms of Delta rockets have been flying since the 1960s, but the only versions left are this and one more Delta IV Heavy set for 2024. The last of the workhorse Delta II launches came in 2018 followed by the final Delta IV Medium in 2019.
“It’s tough. There are definitely some emotions about it knowing what we’ve done,” said David McFarland, the ULA Launch Operations Chief Engineer and Anomaly Lead who has worked on all of the Delta rocket programs going back into the 1980s. “But it’s of extreme pride in seeing what we’ve done for the country, and basically for mankind as well — some of the improvements we’ve made for life around the world.”
This is the 15th launch ever for a Delta IV Heavy that first flew in 2004. While most have been for national security missions, it had two notable missions for NASA: launching the Parker Solar Probe in 2018 and the first flight of the Orion spacecraft that’s now part of the Artemis program on the Exploration Flight Test-1 mission.
“I was here. I remember like it was yesterday,” said NASA Johnson Space Director Vanessa Wyche this past week when appearing at a “Women in Space” event at Kennedy Space Center Visitor Complex. She was working on the Orion project in 2014. “I can remember the liftoff, it taking off, it was so special to me because we had been working on that spacecraft since 2006 probably, in earnest. That was another of the tests that led us up to being able to do Artemis I.”
McFarland said he holds those NASA missions among the most important in ULA’s launch history.
“Our bread and butter has been for national security space, whether it’s the NRO or the Space Force, but those are two shining examples of what we’ve done with the Delta IV Heavy,” he said.
“[Orion] was just an awesome mission to get that program off and running, and then now with Artemis I successfully using that spacecraft as well in the future on Artemis II and III, that’s, again, something to be very proud of,” he said. “And Parker Solar Probe. What an amazing mission that is to be involved with the launch of the fastest thing we humans have ever produced, spacecraft-wise, and the data that’s generated is just an amazing mission.”
Parker Solar Probe whips around the sun flying by at 430,000 mph.
The Delta IV Heavy’s rocket power creates a unique sight with three equally fueled first-stage boosters powered by Aerojet Rocketdyne RS-68A engines that burn through cryogenic liquid hydrogen and liquid oxygen to produce 2.1 million pounds of thrust at liftoff, a thrust only bested by SpaceX’s Falcon Heavy and NASA’s Space Launch System among current orbital flight options.
Even lighting them up on liftoff takes some special care, McFarland said.
“You’ve got three basically first stages together. So what we learned after launching the first few is that to make sure that the huge amount of flame is not endangering the rocket, we actually start one of those boosters first, two seconds before the other two,” said McFarland. “It basically creates a flow so that all of the exhaust coming out of the other two, it’s all sucked down a flame trench and away.”
McFarland said that next year’s final Delta IV Heavy launch likely means the end of ULA’s use for Space Launch Complex 37-B, and it will be handed back in time to the Space Force, from whom they lease the space. Its remaining Atlas and future Vulcan launches will come from Space Launch Complex 41.
ULA’s last launch was November 2022 in California, and hasn’t flown from Cape Canaveral since October. But this mission now joins 29 in the books this year from competitor SpaceX from the Space Coast and one launch from upstart Relativity Space that flew its 3D-printed Terran 1 rocket back in March.
ULA had other rocket launches planned this year, though, that have encountered delays. That includes an Atlas V rocket with the CST-100 Starliner spacecraft that was supposed to bring the first crewed flight to the International Space Station in a targeted July launch that has been delayed to no earlier than fall. The company has also pushed off the first ever Vulcan Centaur launch, the rocket meant to replace both Delta IV and Atlas V rockets.
“So this business is predicated on the customer and their requirements, and that includes calendar-wise, when they want to launch, when they’re capable of launching. So we’ve had a few changes to the manifest this year, where the customer is either not ready or they need more time to get their payload prepared,” McFarland said.
Even this mission, was delayed after finding a valve issue on the rocket this spring.
“We had to go replace that to make sure that the mission succeeds,” he said. “So there’s been various reasons why the manifest has changed and the launch dates have moved, but it’s all within how we do business and we we don’t shirk on our testing requirements … We work toward making mission success our number one goal. Whatever time it takes to do that, that’s what we’re going to do.”
ULA may not be flying as often now as SpaceX, but its future has dozens of launches in the manifest, mostly from Vulcan Centaur once it’s been signed off on.
The first launch, Cert-1, is meant to send a private company Astrobotic’s lunar lander Peregrine to the moon, but also deploy two test satellites for Amazon’s Project Kuiper, a planned massive constellation of internet satellites that will compete with SpaceX’s Starlink constellation.
ULA has been contracted to fly hundreds of Project Kuiper satellites in the coming years including the remaining spate of available Atlas V rockets and 38 more on Vulcan, so the company could get to a cadence of one launch every two weeks.
But for now, Delta IV Heavy and the final vestiges of the storied Delta family of rockets is in the spotlight.
While this is the 15th launch in this heavy configuration, it’s the 44th Delta IV launch overall and 388th ever for the Delta class that began flying in 1960.
They have been used to take up military, government and commercial payloads such as weather, communications and science satellites, robotic exploration probes, eight Mars rovers and the Kepler space telescope.
“These launches place critical capabilities into orbit for our nation and our allies in what are dynamic times for the space community,” said Maj. Gen. Stephen Purdy, the head of Space Launch Delta 45 and executive officer for the Assured Access to Space program run by the Space Force. “Every member of our launch team understands what’s at stake and works with care and efficiency to prepare for what’s going to be a tremendous launch.”