Blue Origin is unlikely to deliver two flight-ready versions of the BE-4 rocket engine to United Launch Alliance (ULA) before at least the second quarter of 2022, two sources say. This increases the possibility that the debut flight of ULA’s much-anticipated new rocket, Vulcan, could slip into 2023.

Vulcan’s first stage is powered by two BE-4 engines, which burn methane and are more powerful than the space shuttle’s main engines. The sources said there recently was a “relatively small” production issue with fabrication of the flight engines at Blue Origin’s factory in Kent, Washington.

As a result of this, the engines will not be completed and shipped to the company’s test stands in West Texas until next year. Once there, each engine must be unpacked, tested, and then re-configured to be moved to ULA’s rocket assembly facility in northern Alabama. A reasonable “no-earlier-than” date for the engines’ arrival at the rocket manufacturer is now April 2022, and this assumes a smooth final production and testing phase.

A lot riding on these engines

ULA declined to comment on specifics about the production issue. However, the company said it was disappointed that it did not receive these two flight engines in 2021 as anticipated.

“We are disappointed that we will not be receiving Vulcan flight engines from Blue Origin by the end of the year, but they will be arriving early next year,” the company said in a statement. “The certification program is moving along very well, and the production engines are being manufactured. We look forward to Vulcan’s first launch in 2022.”

However, it now seems far from certain that Vulcan will make its debut in 2022. And there is a lot riding on this rocket and its timely debut, which will replace both the Atlas and Delta rockets that ULA has flown. The US military is counting on Vulcan to lift about 60 percent of the nation’s national security payloads into space from 2022 to 2027.

Due to delays in development—at one point, the Vulcan rocket was expected to debut in 2020—the US Space Force and ULA have already agreed to move the first military mission assigned to Vulcan, designated USSF-51, onto an Atlas 5 rocket. However, ULA has since said that all of its remaining Atlas rockets, which are being phased out due to reliance on the Russian-built RD-180 engine, are allocated to other missions. It is not clear, therefore, that other military missions can be moved off of Vulcan and onto an Atlas.

Assuming the BE-4 engines arrive at ULA in April, the company would have about eight months to prepare the rocket for a test flight in 2022, which will carry a small lunar lander built by a private company, Astrobotic.

This is the first time that ULA, which was formed out of the launch divisions of Boeing and Lockheed Martin in 2005, has taken delivery of a brand-new first-stage rocket engine as part of booster development. However, when Boeing and Lockheed first used the RS-68 and RD-180 engines for their Delta and Atlas rockets, it took an average of 19.5 months from engine delivery to first flight.

Vulcan is not expected to require this much time to incorporate the BE-4 rocket engine, however. During a reporters roundtable in December 2020, ULA Chief Executive Tory Bruno explained why in response to a question from Ars. Earlier that year, ULA had taken delivery of “pathfinder” engines, which are nearly identical to the flight engines but not designed to be ignited.

https://arstechnica.com/?p=1819172

On Thursday night, United Launch Alliance chief executive Tory Bruno shared an image of a rocket panel on Twitter and declared, “The age of Vulcan has begun…” This is one of the first pieces of metal being cut and formed for the Vulcan-Centaur rocket’s fuel tanks, Bruno later confirmed. “This is a piece of actual first flight hardware,” he told Ars.

The image showed a large machine, at least the size of a freight train car, producing a long, slightly curved panel that will form the barrel components of a fuel tank. The fabrication work was being done inside United Launch Alliance’s factory in Decatur, Alabama.

Bruno characterized the piece as being “bump formed,” a process which occurs after barrel panels are machined. During this process, the panels are formed into cylindrical arcs so that they can be welded into a barrel for fuel tanks. (More about the materials used in aerospace structures and this specific manufacturing process can be found in this NASA document).

In response to a question from Ars about how bump forming works, Bruno explained, ” A giant press ‘bumps’ the panel against two blunt knife edges, progressively ‘potato chipping’ it into a curve. This is done by hand by a highly skilled craftsman.”

The cutting of metal for a rocket that will actually fly into space suggests that United Launch Alliance remains on track toward bringing its Vulcan rocket—a successor to both its Atlas V and Delta boosters—online by 2021. However, the most complex things that must be created for new rockets generally are not fuel tanks, but propulsion and software. The company has made progress in those areas, too, by procuring BE-4 engines from Blue Origin and reusing between 40 to 60 percent of the software from the Atlas and Delta rockets. Integrating all of this will be challenging, but it is better to be working with actual hardware rather than computer simulations.

It’s a good time for United Launch Alliance to demonstrate progress. The Air Force will soon accept bids for military launch contracts from 2022 to 2026, and some of the decision criteria will come from an Air Force assessment of rocket readiness for Vulcan, as well as SpaceX’s Falcon Heavy, Blue Origin’s New Glenn, and Northrop Grumman’s Omega rockets. Vulcan appears to be ahead of all but the Falcon Heavy, which flew one mission in 2018, and has another flight coming as soon as April 7.

https://arstechnica.com/?p=1483103