Rocket Lab has reached a significant milestone by completing the first full assembly of its Archimedes engine, a cutting-edge 3D printed, reusable rocket engine designed for the Neutron medium lift launch vehicle. The Company has commenced an extensive test campaign, including multiple engine system activations, in preparation for the first Archimedes hot fire.
The upcoming Archimedes test campaign will be conducted at Rocket Lab’s specialized engine test stand at NASA’s Stennis Space Center in Mississippi, the largest rocket propulsion test site in the United States. Archimedes, a unique rocket engine powered by liquid oxygen and methane using an oxidizer-rich staged combustion cycle, stands out due to its thrust class, engine cycle, and propellant combination.
Engine reusability is maximized, with the operating point allowing for lower stress levels compared to other rocket engines and a minimum reuse target of up to 20 launches per engine. Each Archimedes engine can produce a powerful 165,000 lbf (733 kilonewtons) at full power, totaling 1,450,000 million lbf on Neutron’s first stage. Critical 3D printed parts, including turbo pump housings, pre-burner and main chamber components, valve housings, and engine structural components, will undergo rigorous testing.
Throughout the test campaign, a series of component, subsystem, and all-up system tests will be carried out to validate Archimedes’ transient start-up, steady-state, and shutdown performance. The engine test and development campaign is a critical factor in determining the schedule for Neutron’s inaugural launch, which the Company has confirmed is anticipated to occur no earlier than mid-2025.
“Having a completed Archimedes engine on the test stand is an inflection point in Neutron’s development program. Now we’ve entered the home stretch where we breathe fire and refine the engine in preparation for the first flight,” said Rocket Lab founder and CEO Peter Beck. “Often with engine development plans, there can be a rush to get a minimum viable product to the stand, after which you have to spend years in redesign and iterative testing to get the performance you need, let alone being able to reproduce it reliably on a large production scale.”
“What we’ve taken to the test stand is very close to a flight-like engine, and with all of our production infrastructure stood up alongside the engine’s development, we’re in a prime position to be able to make quick iterations to Archimedes for a rapid development and qualification campaign. We took the time to not only bring a mature design to the stand that has been thoroughly tested at the component level, but also to stand up the experienced team, manufacturing line, and test facilities required to support long-term production of Archimedes.”
“This approach has ultimately pushed the first flight to mid-2025 at the earliest, but it’s an approach we believe will deliver the frequent flight rates the market needs quickly after flight one. Designing a brand-new rocket engine to meet the market demand for frequent and reliable launches is a complex feat, but it’s something we’ve successfully done before, having launched more than 470 Rutherford engines into space. We look forward to repeating this success with Archimedes.”
Rocket Lab’s production of subsequent Archimedes engines is running in parallel with the ongoing test campaign. Long-lead 3D printed components are already manufactured and undergoing checkouts and analysis for integration and engine full assembly at Rocket Lab’s Engine Development Complex in Long Beach, California.
Recent milestones on the path to the first Neutron launch include the completion of carbon composite flight structures for Neutron’s fairing panels, Stage 1 and Stage 2 tanks, and the reusable Stage 1 structure. Infrastructure development is also progressing rapidly at Neutron’s dedicated launch site at Wallops Island, Virginia, with completed foundation concrete works for Neutron’s launch mount and propellant and gas storage facilities and installation of the site’s 278 ft water tower.
Rocket Lab’s groundbreaking Neutron rocket is powered by the innovative Archimedes, a 3D-printed, reusable rocket engine. Capable of lifting up to 13,000kg, Archimedes is an oxygen-rich staged combustion engine designed for rapid reusability. With nine engines on its reusable first stage, Neutron boasts a total combined thrust of 1,450,000 lbf.
The vacuum-optimized version of Archimedes on Neutron’s second stage shares major components with the first-stage engine and can deliver up to 202,300 lbf (900kN). Designed for multiple restarts, the vacuum-optimized Archimedes can start up to six times while in space to perform complex orbital maneuvers, enabling precise payload delivery in multiple or more complex orbits.
Archimedes is deliberately engineered for optimal performance within a medium-range capacity. This deliberate choice reduces thermal and operational stresses on the engine, enhancing its longevity and dependability to meet the demanding reusability requirements of Neutron.
Rocket Lab’s Engine Development Complex, which is located at its headquarters in Long Beach, California, will be the site for the full-rate production of the Archimedes engines.
