ESA made in beginn 1990 several study for advance Ariane 5 rocket, what let to big Ariane super lourd concept 1991
also they study this interesting Idea
Ariane 5 with TWO Vulcain (HM60) engines with each 800 kN thrust and 220 tons fuel in EPC
The Idea behind the concept is this Problem...
already in 1977 were studies for Ariane with Lox/Lh2 upperstage
those became 1977 to 1982 the Ariane 5R study
aka in Forums "the Ariane 5 Common core booster" design
Note code: P=solid fuel, L=Liquid fuel, H=Lox/LH2 fuel. Number=fuelmass in tons
1977 "Systéme Ariane Véhilcule Habitable"...