Following an afternoon of tests and countdown rehearsals, on the evening of June 7, 2023, Space Launch Complex 41 at Cape Canaveral heard the first roar of United Launch Alliance’s Vulcan Centaur rocket.
The Flight Readiness Firing went smoothly and was a complete success.
United Launch Alliance successfully conducted a booster engine flight readiness firing (FRF) at Cape Canaveral Space Force Station, Florida. The engine start sequence began at T-4.88 seconds, the engines throttled up to the target level for two seconds and then powered down. pic.twitter.com/S4wuYmkV2E— ULA (@ulalaunch) June 8, 2023
The prototype, consisting of Vulcan’s first stage and its Centaur upper stage, fired its two Blue Origin made BE-4 engines for a handful of seconds, providing fundamental data on the rocket’s main systems and the entire launch pad infrastructure and software that will support a future launch.
In an increasingly competitive and diverse Space Economy that has been developing over the last few years, ULA’s main objectives, to achieve with this project that is now reaching its final stages, are:
- Reducing costs of sending payload to orbit, keeping on track along other competitors.
- Enhancing performance of its current technologies and developing new ones, aiming to be more reliable, cost-efficient, and able to adapt to different requests and requirements.
Vulcan is built on United Launch Alliance’s decades-long experience, it features two stages and a 5.4 meter wide fairing, available in two versions: standard, specifically 15.5 m, and long, 21.3 m.
The second stage, called Centaur V, is derived from Centaur III, currently used as second stage in the ULA Atlas V rocket. It is powered by two RL10C engines that provide 106 kN of thrust. This family of engines, using liquid hydrogen and oxygen as propellants, was first introduced back in 1962.
It’s on the first stage that we find most of the new hardware, assembled in ULA’s facility in Decatur, Alabama, that is undergoing layout changes to accommodate the production of future Vulcan main components, such as the fuel tanks.
It is composed of a central booster, or first stage, and a varying number of solid rocket boosters (two to six). The SRBs are fundamental to adapt to the different mission requirements and therefore lower launch costs. The booster, standing 33 meters tall, is the result of a collaboration between ULA and Jeff Bezos’ Blue Origin, providing the two main engines.
BE-4 are liquid methane and liquid oxygen staged combustion engines developed by Blue Origin. Each engine provides 2.4 MN of thrust at sea level and is capable of gimbaling up to 5°.
The engines were initially planned to be used only on Blue Origin’s main project in development, the New Glenn heavy launch vehicle. However, the company reached an agreement with ULA in 2018 to provide BE-4s to power the Vulcan Rocket.
What’s left before the launch
After the successful booster static fire, the rocket has been transported back to ULA’s vertical integration building, while all the data gathered with the test is being analyzed.
ULA stated that the qualification for Vulcan is 98% complete, and the remaining issues to address concern the Centaur V second stage. On March 29, 2023, during a qualification testing run on a second stage test article, a hydrogen leak caused an unexpected explosion that damaged both the test stand and the test article used.
Since then, an investigation has been going on to ascertain the cause, and while ULA proceeded with the Flight Readiness Firing, and will be developing a plan for launch in the coming weeks, there is currently no set date for liftoff until the investigation will be completed.
When that happens, the fairing and payload will be mated with the rocket, and ULA will proceed with Vulcan’s maiden flight. The rocket will be transporting different spacecraft, among which is the Peregrine Lunar Lander developed by Astrobotic, under NASA’s Commercial Lunar Payload Services (CLPS) program.