> 6-10 years from now Ariane Next/SALTO will aims replicate Falcon 9 efficiency and the design will be very similar: reusable, RP-1/LOX, Prometheus engine is si

> 6-10 years from now Ariane Next/SALTO will aims replicate Falcon 9 efficiency and the design will be very similar: reusable, RP-1/LOX, Prometheus engine is similar reusable open cycle engine as Merlin with lots of 3D printed parts. 1. Ariane Next will use a Methalox first stage and a Hydrolox 2nd stage[1], not Kerolox (RP-1). 2. Given how long it took to get Ariane 6 to the launch pad, and its similarities to Ariane 5, 6-10 year is very optimistic. --- 1. From what I understand, this is due to political wrangling. Germany wanted to make the engines for the 2nd stage. IMO SpaceX's approach of using the same engine everywhere is superior.