Archimedes (rocket engine)


Archimedes is a rocket engine burning liquid oxygen and liquid methane in a gas generator combustion cycle.[2][1] It is designed by aerospace company Rocket Lab for its Neutron rocket.[1]

Archimedes engine
Country of originUnited States
New Zealand
DesignerRocket Lab
ManufacturerRocket Lab
ApplicationFirst- and second-stage engine [1]
StatusIn development
Liquid-fuel engine
PropellantLOX / liquid methane[1]
Thrust, vacuum1,075.71 kN (241,830 lbf)[1]
1,100 kN (250,000 lbf) (Vacuum version)[1]
Thrust, sea-level851.42 kN (191,410 lbf)[1]
Specific impulse, vacuum320s+[2]
Specific impulse, sea-level255s+
Used in


Archimedes was presented on December 2, 2021 in a webcast by Rocket Lab CEO Peter Beck.[2] It was presented as a fully reusable, gas generator engine using LOX and methane as propellant, a departure form the company's previous Rutherford, which is electrically pump fed. He stated that it had a thrust of 1 MN (220,000 lbf) and 320 seconds of specific impulse. The same day, the Neutron page on Rocket Lab's website was updated specifying the thrust of the seven Archimedes used on the first stage as 5,960 kN (1,340,000 lbf) at sea level and a maximum thrust of 7,530 kN (1,690,000 lbf) and the upper stage's single vacuum optimized Archimedes at 1,110 kN (250,000 lbf). It is expected to have its first hot-fire test during 2022.[3] In an interview published on CNBC website, Mr. Beck stated that Archimedes would be manufactured in New Zealand and its very simple design had "all the things you want when you have to build an engine that can be reused over and over again.”[4]


Archimedes is presented as a highly reusable liquid-propellant engine using methane and liquid oxygen in a gas generator cycle.[2][1] There are both sea-level and vacuum variants. No specifics are disclosed as to the manufacturing methods.

See alsoEdit


  1. ^ a b c d e f g h i "Neutron Rocket Lab". Rocket Lab. 2021-12-02. Archived from the original on 2021-12-02. Retrieved 2021-12-02.
  2. ^ a b c d Neutron Rocket - Major Development Update (YouTube video). Rocket Lab. 2021-12-02. Retrieved 2021-12-02.
  3. ^ Gebhardt, Chris (2021-12-02). "Neutron switches to methane/oxygen, 1 Meganewton Archimedes engine revealed". NASA SpaceFlight. Archived from the original on 2021-12-02. Retrieved 2021-12-02.
  4. ^ Sheetz, Michael (2021-12-02). "Neutron Rocket Lab". CNBC. Archived from the original on 2021-12-02. Retrieved 2021-12-02.

External linksEdit

  • Rocket Lab Neutron Rocket