All the errors of Hermes, repeated 40 years later. The managers and system engineers of Hermes are still around, these guys should have talked to them.
When I was saying still around, I meant not dead. The two Hermes project managers which I know for a fact are still around are significantly younger than Bill Nelson (to give a benchmark), they are still able to have a technical discussion and they know their turf, if you allow me this judgement.
Arianespace unveils 'Susie' - Reusable spacecraft for crew and cargo missions
Effectively, if SUSIE is approved by minister's council, it will be in the same delays than Ariane NEXT. But I don't know if Ariane NEXT will be capable to launch a 25T spaceship. I have see on an Arianespace document the maximum payload will be about 20T.
Quote from: JEF_300 on 09/19/2022 03:45 amI'm not sure how heavy SUSIE would be, but I bet that it's more than the Ariane 64 payload to LEO, so I bet it actually does need to use it's own fuel to get to orbit. So it would be a reusable upper stage, it's just it's a 3rd stage, not a 2nd. Its mass is given in the press release as 25 t. The press release says this is the payload mass of Ariane 64, but the Arianespace web site only gives a 21.6 t LEO payload mass! If Susie acts as a third stage, then the 25 t could be the payload put into a suborbital trajectory, with Susie then using some of the extra 3.4 t of propellant to get into LEO."Ariane 6 compatibility was defined in terms of Susie’s geometry (length 12 meters and width 5 meters to fit the diameter of the launcher) and its mass (25 tons, corresponding to Ariane 64’s low Earth orbit (LEO) performance)."https://www.arianespace.com/vehicle/ariane-6/"Ariane 64, with four boosters, can place up to 11.5 tons into GTO in dual launch configuration, and up to 21.6 tons into LEO."
I'm not sure how heavy SUSIE would be, but I bet that it's more than the Ariane 64 payload to LEO, so I bet it actually does need to use it's own fuel to get to orbit. So it would be a reusable upper stage, it's just it's a 3rd stage, not a 2nd.
Yes effectively with this evolution, that can be possible. I just have a little question... Did we know the type of the SUSIE's motors? An architecture with many engines like the ESM, or just a single Prometheus?
Maybe learn to walk before attempting to run a marathon. I see a lot of resemblance of the Expert Reentry demonstrator that has been dusting away for nearly a decade.This SUSIE will have a development timeline of over a decade. It could be a future development, phase A study nothing more for this ministerial. A microlauncher is needed to launch Expert and Shefex and execute those test. They should experiment with a lander / reusable suborbital rocket (microlauncher first stage).This shouldn't be on the table at this ministerial!
Quote from: hektor on 09/19/2022 11:20 amAll the errors of Hermes, repeated 40 years later. The managers and system engineers of Hermes are still around, these guys should have talked to them.Sorry, but most of them are in fact no longer around. That is: a lot of them have retired or moved on to other businesses. And industries like Airbus et al. do not make a habit of asking the opinion of their retired engineers and managers before launching (pun intended) another bad idea.But I fully agree with you that SUSIE is repeating all the errors of Hermes. Starting with the unrealistic wet mass of just 25 metric tons for a vehicle that is 5 meters in diameter, is 12 meters long, has a crew compartment for 7 AND also having a 40 cubic meter payload bay AND a 7 metric ton payload capacity. That does not add up. Throw in a multi-ton propellant load and engines strong enough to land the entire thing propulsively and it does not add up AT ALL. Much like the numbers never added up for the initial 10 development iterations of Hermes. And when they finally DID start to add up for Hermes, the vehicle had lost most of its originally promised capabilities.If SUSIE remains marrried to a 25-ton-to-LEO launcher, than it will start losing capabilities and capacities fast, once they start to seriously develop this contraption.This book should be required reading for everyone who works in the European spaceflight industry: https://link.springer.com/book/10.1007/978-3-319-44472-7