So that means 10% more payload for FH to LEO? Then would FH get 60 tons to LEO in reusable mode? What about expendable mode? 70-75 tons? That could mean lots of heavy units for NASA's proposed moon orbiting station, without using the SLS. Several years ago when they were trying to figure out what to do after Shuttle, a lot of guys on this thread said 50 ton units to orbit would be optimal and cheaper with expendable rockets. They were advocating Atlas V heavy, or Atlas V phase II, and Delta IV heavy with solids and cross feed to get to 50 tons. Now SpaceX will soon do it with reusable boosters instead of expendable.
I would assume the numbers on SpaceX's website (7607 kN, 54.4t for FH) are for Block 5.
Steven Clarke: Do you have customers signed up for reused rocket flights? Where is FH?Musk: Yes. Excluded FH, there are three or four more this year signed up on contingency basis. Think we'll see more customers in future. FH sounded easy; actually no, crazy hard. Required redesign of center core. Done with testing. Cores are in final prep. Finished in 2-3 months. Late summer launch.
He also said FH was crazy hard, had to completely redesign the center core, and that the boosters were refurbs. That certainly seems to imply two core versions - F9/booster and FH/center, or vanilla and chocolate if you prefer.
Slight change of subject, if SpaceX is going to have 24 hour turnarounds for the F-9, something fairly drastic has to be done about the leg folding situation. Going to forged titanium grid fins is a seriously expensive, even extreme step. Now that we know the scale of the grid fin improvement, anyone have any ideas about what an iteration on that scale would look like for the legs? Matthew
Question, would the 10% thrust upgrade Elon mentioned in the presser include the vacuum version on the second stage? If so wouldn't that be an immense improvement? Would that possibly explain why we are suddenly talking about S2 recovery again (even if he said it'd be a 'Hail Mary')?
Quote from: ChrisGebhardt on 03/31/2017 12:15 amMusk: New design coming for Grid Fin. Will be largest titanium forging in the world. Current Grid Fin is aluminum and gets so hot it lights on fire... which isn't good for reuse.Seems like the fins will be a part of this upgrade.
Musk: New design coming for Grid Fin. Will be largest titanium forging in the world. Current Grid Fin is aluminum and gets so hot it lights on fire... which isn't good for reuse.
Transcript of the post launch press conference by reddit user robbak: Part 1 Part 2Part 3Part 4
treyreyElon: "The new grid fins will be, should be capable of taking a scorching and being fine. And they'll also have significantly more control authority so that should improve the re-usability of the rocket. But we will actually improve the payload to orbit by being able to fly at a higher angle of attack, and use the aerodynamic elements of the rocket to effectively glide like a big cylinder, it actually does have a L/D (lift / drag ratio) of roughly 1 if flown at the right angle of attack, but you need the control authority, particularly pitch control authority, that's higher than we currently have to achieve that." (Youtube video 31:30)Edit: I believe he said "big cylinder" not fixed wing, based on hi-res video by Travis
Quote from: matthewkantar on 04/01/2017 01:40 amSlight change of subject, if SpaceX is going to have 24 hour turnarounds for the F-9, something fairly drastic has to be done about the leg folding situation. Going to forged titanium grid fins is a seriously expensive, even extreme step. Now that we know the scale of the grid fin improvement, anyone have any ideas about what an iteration on that scale would look like for the legs? MatthewIMHO, landing back on the launch mount for RTLS is really the only way to achieve a true 24 hour turnaround. No leg upgrade needed! Ducking and running now...
I'm not sure what the mechanism is for improving payload? A smaller "boostback" / targeting burn?
Any chance the new grid fins will pop open on ascent?
Quote from: cscott on 04/01/2017 11:34 amAny chance the new grid fins will pop open on ascent? Doubt it. When Musk talks about extra control and higher angles of attack being flown due to the new grid fins, I think he's talking about descent only. Higher angle of attack would then create higher drag on entry and allow prop savings for both the entry and landing burns.
Get rid of the legs. Use a mobile, teleoperated vehicle not unlike the folding jackscrew one soon to be deployed, but instead capture the landing vehicle at the attach points with inverse legs / "tulip" fixtures.