SpaceX needs to juggle two competing drives.First, get F9B5 going already - stable, cheap to turn around, capable - in order to take advantage of the lead they currently have.Second, they need to get ready to compete with whatever it is BO is gong to field (NG). It would be negligent on SpaceX's part to assume that a second comer, with all the benefits of hindsight, won't be a better rocket than the current F9/FH system. (Better means lower cost, easier to reuse, perhaps a reusable second stage, etc).I do not know how they intend to compete with NG. With upgrades to F9/FH, or by finding ways to use BFR.But while IMO they can ignore the competitive thread from the forthcoming "expendable+" rockets, they can't just assume that BO won't compete with them directly.I don't even know if SpaceX has that plan ironed out, but if I were them, I'd leave enough design space in F9/FH to at least allow for a path forward.
Second, they need to get ready to compete with whatever it is BO is gong to field (NG). directly.
ITS presumably brings an entirely different equation to the mix, in terms of cost per pound to orbit.
Quote from: M.E.T. on 03/07/2017 05:54 amITS presumably brings an entirely different equation to the mix, in terms of cost per pound to orbit.Only if you are launching a lot of pounds! Beyond what it is designed far, large payloads to Mars, it's not clear there's any other likely use for it for many years to come. SpaceX have said it's only for Mars.
Quote from: M.E.T. on 03/07/2017 05:54 amITS presumably brings an entirely different equation to the mix, in terms of cost per pound to orbit.Only if you are launching a lot of pounds! Beyond what it is designed far, large payloads to Mars, it's not clear there's any other likely use for it for many years to come. SpaceX have said it's only for Mars. Ok if something like CISLunar1000 took off then maybe there will be demand for large payloads to the moon and/or space stations. But that's rather OT.It seems at the moment that SpaceX think F9 B5 and FH will cover likely demands for years.
Quote from: FutureSpaceTourist on 03/07/2017 06:15 amQuote from: M.E.T. on 03/07/2017 05:54 amITS presumably brings an entirely different equation to the mix, in terms of cost per pound to orbit.Only if you are launching a lot of pounds! Beyond what it is designed far, large payloads to Mars, it's not clear there's any other likely use for it for many years to come. SpaceX have said it's only for Mars. They never said it is only for Mars. They said they will not make any design compromises for other goals. Adding means to deploy satellites will not break the bank.If their cost estimates are anywhere near realistic, they can compete with launch cost of the Electron Small Sat launcher on a per launch basis, not by weight only.
The estimate I saw for New Glenn's payload capability was between 35-70 tons to LEO. Falcon Heavy sits pretty much in the middle part of that range, and that's before Block 5 comes online, which may push it even higher.
Quote from: meekGee on 03/06/2017 04:55 pmThat said, B5 can follow the F9 1.1 model. No, it can't. Because hardware added after Block 5 would negate the certification. They are not going to scar vehicle for future mods. That is the whole point of Block 5. They will be done with development on Falcon 9 and only other future mods will be to fix problems and not to add a capability. Quote from: meekGee on 03/06/2017 04:55 pmI can't rule out that legless/cradle flights.....I can and that is not an opinion. Spacex has said they are done with F9 development after Block 5 on multiple occasions to multiple people.
That said, B5 can follow the F9 1.1 model.
I can't rule out that legless/cradle flights.....
Before Semmel's observation, I was of the same opinion - that we might (might!) see F9 cradle landing as an isolated test towards BFR, sone on a land-based cradle, and that's that.Semmel made a good connection in that barge fly-back, which presented so many difficulties when thought through, would become a lot easier if there was cradle landing there.[...]I can't rule out that legless/cradle flights are "designed in", but that the bottom-side thrusters are not even designed yet, just anticipated in the design.
Also, how do you know that a cradle landing requires certifiable changes to the upcoming F9B5?
I don't even know if SpaceX has that plan ironed out, but if I were them, I'd leave enough design space in F9/FH to at least allow for a path forward.
They never said it is only for Mars. They said they will not make any design compromises for other goals. Adding means to deploy satellites will not break the bank.
I'm going to ignore ITS because I think it's a ridiculous idea and at least 10 years from being a real thing.
Quote from: meekGee on 03/06/2017 04:55 pmBefore Semmel's observation, I was of the same opinion - that we might (might!) see F9 cradle landing as an isolated test towards BFR, sone on a land-based cradle, and that's that.Semmel made a good connection in that barge fly-back, which presented so many difficulties when thought through, would become a lot easier if there was cradle landing there.[...]I can't rule out that legless/cradle flights are "designed in", but that the bottom-side thrusters are not even designed yet, just anticipated in the design.Please dont forget that I made my observation on the assumption that SpaceX wants to develop Barge flyback. Which is a big assumption.The question for me currently is: what is the reason for the current uncertainty in F9 landing position? It is fantastically accurate but for a cradle landing it has to improve. Is it actually flying F9 to the accuracy required? Or is it knowing the location relative to the ground that is the limiting factor? Do we have any information on that?
All SpaceX really needs to do is fly every 2 or 3 weeks for 12 months and show they can manage that flight rate.They have a lot of other non-booster capabilities to develop first. Dragon 2, Brownsville Launch pad, vertical integration, FH at VAFB (if ever needed), space suits, design, build, deploy and manage the largest satellite constellation every. Just a couple things.I'm going to ignore ITS because I think it's a ridiculous idea and at least 10 years from being a real thing.Edit: And build crew access and egress at LC39A.