Relativity Space intends to use the small Aeon 1 engine it is developing to power its first rocket for only a few flights. Instead, the company plans to quickly perform a “block upgrade” for the Terran 1 rocket, which will serve as a bridge to the much larger, more capable Terran R rocket.

“We’ve always envisioned Terran 1 being a development platform,” said Tim Ellis, the co-founder and chief executive of Relativity Space, in an interview with Ars.

The California-based company, which seeks to 3D-print the majority of its rocket parts, is continuing to work toward the first launch of Terran 1 this year. Powered by nine Aeon 1 rocket engines, this small rocket has a lift capacity of 1.25 metric tons to low Earth orbit. This first Terran 1 mission will not carry any customer payloads in order to focus on the rocket itself and is called “Good Luck, Have Fun.” The name is a reference to what players say to one another before a video game begins, Ellis said.