Nammo’s British Rocket Engine Powers Israel’s Mission to the Moon

When SpaceIL’s Beresheet Lunar Lander blasts off from Cape Canaveral on a SpaceX Falcon 9 later this week it will carry a rocket engine designed and built at Nammo’s facility at Westcott in the UK. Known as the LEROS 2b, and originally designed for satellites and deep space missions, the engine will power the lander during its transfer to the Moon, place it into orbit around the moon, and ensure a safe landing on the lunar surface. Finally, the rocket will be used to ‘hop’ and move the lander to another location on the moon approximately 500 m from its original landing point.

“We are very excited to be part of this project” said Robert Selby, General Manager of Nammo Westcott. “When mission engineers presented the operational requirements for the lander, it was clear that it would not be a straightforward mission. Over the past few years we have made a series of adjustments and improvements to ensure that it will be able to work not only in space, as it was originally designed for, but also power a spacecraft during landing.”

Model of the Beresheet. Photo: SpaceIL

Originally conceived during a conversation in a bar between three friends, the Beresheet aims to inspire young people to become engineers by generating interest around space exploration. Nammo Westcott in Buckinghamshire was chosen by SpaceIL as the provider of the main rocket engine in 2015. Modifications made to the LEROS since then include shortening the nozzle to ensure it will fit within the spacecraft and, crucially, not hit the surface of the moon when the lander touches down. Nammo’s engineers have also increased the thrust of the engine to give it sufficient power to land safely. Finally, they have verified that the engine is able conduct multiple so-called “hot re-starts” during landing and the 500 meter hop on the Moon.

“The hot re-starts represented a particular challenge as it effectively puts the engine into its most stressful temperature environment. To test this we performed a series of hotfire trials together with SpaceIL, where we stopped and started the engine repeatedly, which confirmed that it is able to operate in this highly demanding firing mode,” said Robert Westcott, one of Nammo's lead propulsion engineers on the Beresheet project.

In addition to the changes to the engine, Nammo its industry partners have created a unique, state-of-the-art support structure and heat shield for the engine utilizing the advantages of modern Additive Layer Manufacturing (ALM) techniques to produce a strong, light weight structure suitable for the mission.

“LEROS engines have already powered missions to Mars, Mercury and Jupiter, but never to the Moon, and certainly never powered a landing. I think the Beresheet will show why the engine has remained such a popular design for nearly three decades, and why it remains one of the best of its kind even today,” said Robert Selby.

Previous missions using LEROS include NASA's Juno spacecraft, which in 2016 entered orbit around Jupiter following a successful braking burn by its Leros 1b engine. Photo: NASA