Prometheus (rocket engine)

{{Infobox rocket engine

| image = Maquette du moteur-fusée Prometheus IAC 2022.jpg

| caption = Model of the Prometheus rocket engine, featured at IAC 2022.

| country_of_origin = France
European Union

| designer = ArianeGroup

| manufacturer = Ariane Group

| associated = Themis{{, }}Ariane Next

| type = liquid

| fuel = {{chem2|CH4|link=liquid methane}}

| oxidizer = LOX

| cycle = Gas-generator

| thrust(SL) = {{cvt|980|kN}}

| chamber_pressure = {{cvt|100|bar}}

| throttle_range = 30% to 110%

}}

The Prometheus rocket engine is an ongoing European Space Agency (ESA) development effort begun in 2017 to create a reusable methane-fueled rocket engine for use on the Themis reusable rocket demonstrator and Ariane Next, the successor to Ariane 6, and possibly a version of Ariane 6 itself.{{Cite conference |last=Patureau de Mirand |first=Antoine |date=July 2019 |title=Ariane Next, a vision for a reusable cost efficient European rocket |url=https://www.eucass.eu/index.php/component/docindexer/?task=download&id=5506 |format=PDF |conference=8th European Conference for Aeronautics and Space Sciences |doi=10.13009/EUCASS2019-949 |access-date=18 August 2021}}

Prometheus is a backronym from the original French project designation PROMETHEE, standing for "Precursor Reusable Oxygen Methane cost Effective propulsion System", and for the Titan Prometheus, from Greek mythology, creator of humanity, and god of fire, known for giving fire to humanity in defiance of the gods.

By 2020, the program was funded and is under development by ArianeGroup.

The engine is aimed to be reusable with substantially lower costs than traditional engines manufactured in Europe. The cost goal is to manufacture the Prometheus engine at one-tenth the cost of the Ariane 5's first-stage engine.

General characteristics

The engine is planned to have the following features:

Methane–oxygen propellant.
Extensive use of metal 3D printing (up to 50% of the engine).
Open gas-generator cycle.{{Cite conference |last=Iannetti |first=A. |last2=Girard |first2=N. |last3=Tchou-kien |first3=D. |last4=Bonhomme |first4=C. |last5=Ravier |first5=N. |last6=Edeline |first6=E. |date=July 2017 |title=PROMETHEUS, A LOX/LCH₄ REUSABLE ROCKET ENGINE |url=https://www.eucass.eu/doi/EUCASS2017-537.pdf |conference=7th European Conference for Aeronautics and Space Sciences |doi=10.13009/EUCASS2017-537 |access-date=2 March 2019}}
980 kN of thrust (~100 tonnes), variable from 30% to 110% thrust.
{{convert|100|bar|abbr=on}} chamber pressure.
360 s specific impulse (I{{sub|sp}}).{{citation needed|date=December 2020}}
Reusable 5 times.{{cite web |title=PROMETHEUS |url=https://cnes.fr/en/projects/prometheus |website=CNES (Centre national d'études spatiales) |access-date=6 May 2025}}
Around 1 million euros production cost.

== History ==

The European Space Agency (ESA) began funding Prometheus engine development in June 2017 with {{Euro|85 million}} provided through the Future Launchers Preparatory Programme, 63% of which came from France.{{Cite news |last=Henry |first=Caleb |date=5 October 2017 |title=France's Prometheus reusable engine becomes ESA project, gets funding boost |url=https://spacenews.com/frances-prometheus-reusable-engine-becomes-esa-project-gets-funding-boost/ |access-date=9 January 2018 |work=SpaceNews}}

By June 2017, Patrick Bonguet, lead of the Ariane 6 launch vehicle program at Arianespace, indicated that it was possible the Prometheus engine could find a use on a future version of the expendable Ariane 6 launcher. In this scenario, a "streamlined version of Vulcain rocket engine called Vulcain 2.1 would have the same performance as Vulcain 2". The expendable Ariane 6 was then expected to make an initial launch in 2020.{{Cite news |last=Henry |first=Caleb |date=8 January 2018 |title=France, Germany studying reusability with a subscale flyback booster |url=https://spacenews.com/france-germany-studying-reusability-with-a-subscale-flyback-booster/ |access-date=9 January 2018 |work=SpaceNews}}

By June 2020, the ESA was on board with this plan and had agreed to completely fund the development of the Prometheus precursor engine to bring the "engine design to a technical maturity suitable for industry". The objective of the overall program as stated in June 2020 was to utilize Prometheus technology to eventually "lower the cost of production by a factor of ten of the current main stage Ariane 5 Vulcain 2 engine".{{Cite web |date=4 June 2020 |title=ESA moves ahead on low-cost reusable rocket engine |url=https://www.esa.int/Enabling_Support/Space_Transportation/ESA_moves_ahead_on_low-cost_reusable_rocket_engine |access-date=4 June 2020 |publisher=European Space Agency}}

In 2021, ESA invested an additional €135 million in the project,{{Cite web |date=17 May 2021 |title=New ESA contracts to advance Prometheus and Phoebus projects |url=https://www.esa.int/Enabling_Support/Space_Transportation/New_ESA_contracts_to_advance_Prometheus_and_Phoebus_projects |archive-url=https://web.archive.org/web/20240113002602/https://www.esa.int/Enabling_Support/Space_Transportation/New_ESA_contracts_to_advance_Prometheus_and_Phoebus_projects |archive-date=13 January 2024 |access-date=25 October 2024 |publisher=European Space Agency}} including €30 million from DLR.{{Cite web |date=28 May 2021 |title=Prometheus: Contract signed for the expansion of test capacities with LOX methane |url=https://www.dlr.de/en/ra/latest/news/prometheus-contract-signed-for-the-expansion-of-test-capacities-with-lox-methane |access-date=25 October 2024 |publisher=German Aerospace Center}}

A Prometheus engine was started up in Nov 2022.

The engine had a successful 12 second test firing in June 2023, at the THEMIS test stand in Vernon, France.{{Cite news |last=Richards |first=Bella |date=23 June 2023 |title=Themis, Prometheus complete first hot-fire tests in France |url=https://www.nasaspaceflight.com/2023/06/themis-prometheus-hot-fire-test/ |access-date=14 July 2024 |work=NASASpaceflight |language=en-US}}

An additional successful hot fire test was reported at the end of 2024.{{Cite web |last=Parsonson |first=Andrew |date=2025-01-14 |title=ArianeGroup Completes Key Prometheus Hot Fire Test |url=https://europeanspaceflight.com/arianegroup-completes-key-prometheus-hot-fire-test/ |access-date=2025-01-14 |website=European Spaceflight |language=en-US}}

References

External links

[https://www.esa.int/Enabling_Support/Space_Transportation/Prometheus_to_power_future_launchers ESA Prometheus website]

Category:Rocket engines using methane propellant

Category:Space programs

Category:European space programmes

Category:Spaceflight technology

Prometheus (rocket engine)

General characteristics

See also

References

External links