An all-liquid version of the Ariane 6?

[Exoscientist]

 The currently cited price of the Ariane 6 is €75 million($80 million) for the two SRB version and €115 million($125 million) for the four SRB version. But this is 2 and 3 times higher than the price of the Falcon 9 used at $40 million. If ArianeSpace proceeds to offer the Ariane 6 at those prices then like ULA they will be driven to the brink of bankruptcy.

 It is important to note the high price of the Ariane 6 is coming solely from the high price of the solid side boosters. Note the €40 million added to the price for the two added SRBs of the four SRB version compared to the price of the two SRB version suggests a price for two SRB’s as €40 million. But this would mean the entire rest of the rocket aside from the SRB’s would be €35 million.  The two SRB’s on the two SRB version would cost more than the price for the entire rest of the rocket.

 This gives us a clue for what is going so terribly wrong with the pricing of the Ariane 6. Usually, with solid side boosters their size in mass is ~1/10th the size of the core stage. But with the Ariane 6 the side boosters are the size of the core stage itself. Imagine how high would be the price of the Delta IV and Atlas 5 if those familiar side boosters they often use were each 10 times their current size.

 So based on that I wanted to see what could be done if we eliminated the SRB’s and just added 1 or 2 additional Vulcains to the core for sufficient thrust for take-off.

So that’s the challenge:

What would be the payload to LEO if the Ariane 5 core had 1 or 2 additional Vulcains added to the core and no SRB’s? 

I stated the Ariane 5 core because its propellant mass and dry mass are known, while the numbers for the Ariane 6 core are up in the air.

Note with only 2 Vulcains on the core and no SRB’s you could only use a small second stage for it to be able to lift off. I recommend the Ariane 4 H10 hydrolox upper stage at ~10 ton propellant load.

 With 3 Vulcains on the core though you would have sufficient take-off thrust for a larger upper stage; it could be 30, 40, or even 50 tons propellant load.

   Robert Clark

Edited July 10, 2023 by Exoscientist