Where do you get SLS getting 2.5 times the LEO payload vs FH?
Right now, EM-1 is giving me uncomfortable Ares-I-X flashbacks.
Quote from: spacenut on 04/29/2016 07:35 pmWhere do you get SLS getting 2.5 times the LEO payload vs FH? Mr. Kyle was referring to escape velocity payload, not payload to LEO.
The Raptor upper stage engine is supposed to be developed in the next 18-24 months
The gap between Apollo 7 and Skylab 2 was even greater, 4 years 7 months and 14 days. Similarly the Delta II has some pretty big gaps in its recent launch history. The gap between Delta flight 357 and 367 is 2 years 8 months and 4 days. There is an almost 2 year gap between the last Delta II flight and the next one.
Accordingly I don't think the issue of launch cadence as it relates to reliability should be a factor the decision to continue or cancel the program.
There are many pros and cons to the SLS program that are way more important than this hypothetical concern.
And Spacenut clearly mentioned:Quote from: spacenut on 04/29/2016 07:35 pmThe Raptor upper stage engine is supposed to be developed in the next 18-24 monthsI surely imagine the Raptor US will fly on a FH long before EUS flies on an SLS Block IB. With FH now based on Falcon 9 v1.1FT, if cross feed were employed on a fully disposable FH with Raptor US, I highly doubt Block IB would get 2.5 x the payload to GTO or escape.
I think MCT (at least the BFR booster) may fly before SLS Block IB ever does. In fact, I think a single Block I will fly. I now believe Blocks IB and IIB will never see the sky.
Given how much trouble and hard work SpaceX has had to do to get Falcon Heavy off the ground I doubt BFR will be flying until at least 2025.
You're working off of incorrect presuppositions. SpaceX has been smart enough to finish their refinements of F9 before proceeding to FH. .....Putting FH on hold while refining F9, mastering RTLS and at sea landing, then proceeding with FH has been a strategically shrewd, intentional, and practical move. There has been nothing troublesome or problematic about it.
.... Ares I-X had only the first stage operational, the upper stage and LAS were dummies.
Quote from: Endeavour_01 on 04/29/2016 07:54 pm.... Ares I-X had only the first stage operational, the upper stage and LAS were dummies.No, it was worse than that. The Ares-1X first stage was not operational either. It was a standard four-segment Shuttle SRB with a dummy fifth segment bolted on top to make it look like a 5-segment RSRMV. The fifth segment was weighted down with ballast to simulate the mass of a real fifth segment. Which of course made the booster so heavy that the steel motor casing bent when it parachuted into the ocean.Cheers!
Someone figured several years ago, that if they stayed with the 4 seg solids and 5 SSME's and a good upper stage, they could have flown 4-5 times a year for $1 billion.
Now one time for $1 billion. To me it is sad.
maybe Im confused on the whole payload funding thing, but what SLS payloads has NASA proposed that Congress has not funded?
I think BFR would be easier than Falcon Heavy, or heavy of any rocket.
Quote from: chrisking0997 on 05/02/2016 04:28 pmmaybe Im confused on the whole payload funding thing, but what SLS payloads has NASA proposed that Congress has not funded? For info on SLS payloads (manifest plans) or lack thereof see this thread: http://forum.nasaspaceflight.com/index.php?topic=39300.0Currently there is Orion and DSH (DSH only recently in FY2016 started receiving any funding). With Europa investigating SLS suitability. It is both a problem of NASA putting forth more candidates and congress funding them. NASA doesn't want to put a new program in front of congress if they know it has almost no chance of getting funded. They wait for funding chance to increase before trying to get it funded. Look at what has happened to ARM.
It is now law that the Europa mission will use SLS. That is about as firm of a payload as you can get. I don't even think that Orion and DSH are required legally to be launched on SLS and so those are comparatively less firm.
Quote from: oldAtlas_Eguy on 05/02/2016 05:41 pmQuote from: chrisking0997 on 05/02/2016 04:28 pmmaybe Im confused on the whole payload funding thing, but what SLS payloads has NASA proposed that Congress has not funded? For info on SLS payloads (manifest plans) or lack thereof see this thread: http://forum.nasaspaceflight.com/index.php?topic=39300.0Currently there is Orion and DSH (DSH only recently in FY2016 started receiving any funding). With Europa investigating SLS suitability. It is both a problem of NASA putting forth more candidates and congress funding them. NASA doesn't want to put a new program in front of congress if they know it has almost no chance of getting funded. They wait for funding chance to increase before trying to get it funded. Look at what has happened to ARM.It is now law that the Europa mission will use SLS. ...