WASHINGTON — United Launch Alliance plans to resume tanking tests of its Vulcan Centaur rocket and test fire its main engines as early as next week, the company announced May 11.
“Vulcan is in position atop SLC-41 at Cape Canaveral Space Force Station to undergo a full launch day rehearsal tomorrow and flight readiness firing test of its main engines planned for next week,” ULA said.
ULA rolled the rocket on Thursday to Space Launch Complex 41 in preparation for tests.
ULA’s CEO Tory Bruno in tweets on Wednesday said Vulcan was returning to tanking tests although the investigation of a Centaur upper-stage testing anomaly that occurred on March 29 has not yet been completed.
ULA has not provided a new target launch date for Vulcan.
“With success here, and a resolution of the Centaur V ground test anomaly, we are projecting for a Vulcan Cert-1 launch this summer,” Bruno wrote.
Cert-1 is the first of two certification launches that Vulcan must complete to be able to fly national security launch missions for the U.S. Space Force.
The debut launch will carry Astrobotic’s Peregrine lunar lander, two demonstration satellites for Amazon’s Project Kuiper broadband constellation and a payload for space memorial company Celestis.
ULA preparing for Vulcan Centaur static fire

WASHINGTON — United Launch Alliance expects to conduct a static-fire test of its Vulcan Centaur rocket in several days, but the timing of the vehicle’s first launch will depend on the outcome of an ongoing investigation of a test anomaly.
ULA rolled the Vulcan rocket from the pad at Space Launch Complex 41 at Cape Canaveral, Florida, back to its Vertical Integration Facility (VIF) building on May 15. The vehicle had been on the pad for several days to conduct a tanking test and practice countdown.
Tory Bruno, president and chief executive of ULA, said in a May 15 tweet that the company needed to “adjust a handful of parameters and set points” for the vehicle before performing what the company calls the Flight Readiness Firing (FRF), a static-fire test of the booster’s BE-4 engines on the pad. That work would be done while the rocket is back in the VIF.
In a May 16 interview after a speech at the Humans to Mars Summit here, Bruno said that work involved a combination of minor adjustments to both pad infrastructure and the vehicle. The former includes adjusting set points in a hydraulics system and changing the rate of liquid oxygen flowing into the rocket to top off tanks after recycling the countdown. Those adjustments, he said, could be done in software.
On the booster, he said there was an issue during the pad tests with flowing gas through spark torch igniters used to ignite the BE-4 engines. The gas is intended to make sure that the igniters are dry and can light, but the timing was off. That could involve some combination of adjustments on the rocket and ground infrastructure.
“There’s nothing wrong with the engines,” he added. “We’ve lit the engines a zillion times on the test stand at Blue,” a reference to test stands by engine manufacturer Blue Origin.
That work is done more easily inside the VIF, he said, where there is protection from the weather and where work can continue when other range operations might cause a halt to work on the pad.
Once those fixes are complete, Bruno said the vehicle will roll back out to the pad for the FRF. “It’ll be a few days,” he said of the timing of the test, which will depend on both when the work is complete and getting approval from the range for test, which is required since it is considered an “energetic” event.
Assuming there are no problems with that firing, the last major obstacle before launch is completing an investigation into a March 29 incident during testing of the Centaur upper stage. Hydrogen leaked from the structural test article and ignited, creating a fireball.
Bruno said the investigation was delayed because it took time to remove equipment on top of the Centaur, such as a payload adapter and mass simulators for the payload and payload fairing. Only in the last week and a half was ULA able to get access to the dome section of the Centaur where the leak was located.
Engineers have isolated a small region on that dome where they believe the leak came from, as well as the likely ignition source. “I’m pretty confident that we’re going to find the leak, and once we find the leak we’ll know if we have to take corrective action or not on the flight vehicle,” he said.
If ULA doesn’t need to modify the Centaur, that would allow the Cert-1 launch to take place in early summer, he said. “If we do, it could take longer, but I don’t expect it to get out of the year.”
Complicating launch scheduling is the requirement for the primary payload, the Peregrine lunar lander from Astrobotic, which has a launch window that is open only for about four to five days per month. Before the Centaur test anomaly, ULA had been working towards a May 4 launch, which Bruno said in February was the start of a window about four days long.
“In the big picture, it’s a steel pressure vessel and it had a leak,” he said. “We’re going to understand it and we’re going to fix it. It’s not like other things that go wrong on rockets like engines that blow up. It’s just a piece of structure. We’ll fix it.”
Quelle: SN
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Update: 26.05.2023
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Watch Vulcan Centaur rocket test-fire its engines on the launch pad for 1st time today
The test is set for 6 p.m. on Thursday (March 25).

Update for 9 a.m. on May 25: United Launch Alliance (ULA) has confirmed the Flight Readiness Firing (FRF) test of its new Vulcan Centaur rocket will happen at 6 p.m. EDT (2200 GMT) on Thursday (May 25). Watch it here courtesy of ULA.
United Launch Alliance (ULA) is gearing up for a critical test firing of its next-generation rocket after a recent fueling check, and it could happen as soon as this week.
On Monday morning (May 22), Bruno stated on Twitter that the company's new Vulcan Centaur rocket was returning to Space Launch Complex 41 at Cape Canaveral Space Force Station. Now that the rocket is back at the pad, Vulcan's static fire test (in which the rocket's engines are ignited while it remains on the ground) could happen any day. "We are targeting as soon as tomorrow for the Flight Readiness Firing," a representative from ULA told Space.com on Tuesday (May 23), "but it will depend on range availability." On Wednesday (March 24), ULA CEO Tory Bruno intimated on Twitter that the test could happen as soon as Thursday (March 25).
If all goes according to plan, and Vulcan's static fire and wet dress rehearsal go smoothly, the rocket's first launch will be its next major milestone. Bruno has previously indicated sometime in June or July as Vulcan's earliest likely launch date, with launch windows available 4 to 5 days every month.
ULA previously completed a successful tanking test on the company's new Vulcan on May 12, filling the rocket with over a million pounds of fuel during the test. ULA engineers then evaluated the fueling test results against Vulcan's design expectations.
Two days after the successful tanking, Bruno indicated in a May 15 tweet that the tests were "good," but that teams would be making some parameter adjustments ahead of Vulcan's first static fire. That milestone moved Vulcan one step closer to its first launch, with only a static test firing of the engines and wet dress rehearsal left to validate the vehicle.
The rocket's main booster BE-4 engines use liquified natural gas (LNG) and liquid oxygen for fuel, and will be able to produce over half a million pounds of thrust at liftoff. Vulcan's Centaur V second stage RL10 engines are powered using liquid hydrogen and liquid oxygen.
The 202-foot (62-meter) Vulcan Centaur will be capable of lifting 7.7 tons (7 metric tonnes) of payload to geostationary orbit, over 22,000 miles (36,000 km) above the Earth. The rocket was designed to replace ULA's veteran Atlas V and Delta IV launch vehicles that have been in service for two decades.
Already, NASA has added Vulcan to its lineup of rockets for future missions. Amazon has also contracted ULA for 38 Vulcan launches to support the deployment of its Project Kuiper communications satellite constellation.
Quelle: SC
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Update: 9.06.2023
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What you need to know about United Launch Alliance's Vulcan rocket test fire

Update: (9:45 p.m. EDT, Wednesday, June 7) United Launch Alliance successfully completed a six-second engine test fire of the Vulcan rocket at 9:05 p.m. EDT at Cape Canaveral Space Force Station.
Update: (8:30 p.m. EDT, Wednesday, June 7) The window for the "flight readiness firing" of ULA's Vulcan rocket can extend for hours.
United Launch Alliance completed a six-second test fire of the two BE-4 engines of its new Vulcan Centaur rocket for the first time on its launch pad at Cape Canaveral Space Force Station at 9:05 p.m. EDT, Wednesday night, June 7.
What we know about the Vulcan Centaur test fire:
United Launch Alliance teams are working toward a first-time engine test of the company's next-generation Vulcan Centaur rocket, known as a "flight readiness firing."
ULA teams rolled the rocket to its launch pad Tuesday. Fueling procedures got underway earlier this afternoon ahead of this evening's test, which will fire up two Blue Origin-built BE-4 engines at the business end of the company's new rocket.
During the test, the engines will throttle up to full power and run for about six seconds. It's expected to generate about a million pounds of thrust, but the rocket will remain on the launchpad held down by powerful restraining mechanisms.
Vulcan Rocket Arrives on the Space Coast
United Launch Alliance's next generation rocket, the Vulcan Centaur, arrives at Port Canaveral
What's the purpose of the engine test fire?
The "flight readiness firing" is a critical testing milestone that the company must ace ahead of the debut flight of the Vulcan, which arrived on the Space Coast in January. Since then, ULA teams have been putting it through the testing paces, checking out everything from its fit on the pad to filling its tanks with propellants and running through mock countdowns.
"FRF is really about confirming the operational readiness of the integrated system: launch vehicle, ground systems, facilities and the associated software. In addition, we will demonstrate the ability to successfully execute the engine start sequence and validate our hot-fire abort response procedures," Dillon Rice, ULA's Vulcan launch conductor, said in a release.
Once completed it will help pave the way for the rocket's debut launch set for later this summer.
Meet Vulcan Centaur: United Launch Alliance's newest rocket at Cape Canaveral Space Force Station
What is Vulcan Centaur?
“Vulcan is a powerful rocket with a single core booster that is scalable for all missions, including heavy class performance normally requiring a Delta IV Heavy configuration,” Tory Bruno, ULA’s president and CEO, said in a release.
It’s powered by two massive BE-4 main engines, purchased from Blue Origin, and can be outfitted with up to six solid rocket boosters to provide extra thrust. It's designed to take over the launching responsibilities of the company’s aging Atlas V rocket and the soon-to-be-retired Delta IV Heavy rocket.
Standing 202 feet tall, Vulcan will liftoff from the Cape’s Pad 41, the same pad currently used to launch Atlas V rockets from Florida. Vulcan is designed to be discarded into the ocean after every launch, but ULA is working on plans to recover the valuable engine sections.
What happens after the test ends?
After the test fire, the rocket will be emptied of propellants, fully secured, and returned to United Launch Alliance's Vertical Integration Facility for pre-flight processing.
Two solid rocket boosters and the debut payload will be installed on the next-generation rocket ahead of the first demonstration mission, which could happen as early as this summer.
Quelle: Florida Today