Quote from: tdperk on 08/11/2017 04:25 pmAnd yes, payload to LEO is the proper comparison, because most payloads go there, and all can be designed to depart from there to any destination with no relevant* loss in mission capabilities.SLS Block 1B is being designed to boost 32 metric tons (tonnes) trans-Mars. Falcon Heavy Expendable is expected to lift 16.8 tonnes trans-Mars. These - or similar numbers to points beyond LEO - are the valid comparisons. The LEO-rendezvous Falcon Heavy alternative that you propose would require a new deep-space stage, a propellant depot setup, lots of LEO parking capability that doesn't exist, etc. - all of which would cost lots of cash. Much of the LEO mass capability of a Falcon Heavy would be lost to "tare weight", propellant boiloff, parking orbit RCS propellant, etc. Only about 60% of the liftoff weight of an HTV, for example, is actual cargo. - Ed Kyle
And yes, payload to LEO is the proper comparison, because most payloads go there, and all can be designed to depart from there to any destination with no relevant* loss in mission capabilities.
" The LEO-rendezvous Falcon ... is actual cargo. " <-- Nothing you have said here is true and relevant, as you presume the use of non-optimal architectures which are easily avoided.
Quote from: tdperk on 08/11/2017 05:19 pm" The LEO-rendezvous Falcon ... is actual cargo. " <-- Nothing you have said here is true and relevant, as you presume the use of non-optimal architectures which are easily avoided. What is the "optimal" alternative architecture?
How much does the currently non-existing hardware needed to make it work cost to develop, build, and fly?
Dunno, but if the 130+ tons one SLS will lift are instead lifted with FH's, you get up to $750mn saved from the Atlantic to work with.And the TMI for an FH reusable is about 11.7 long tons to go by past history (I don't know where you are getting 4,900kg from), so you get to keep the rockets. I'm generously (to ULA) calling the per launch FH cost to be $250mn per, where the quoted cost is $90mn.A deep space tug/stage is required anyway.
Quote from: tdperk on 08/11/2017 06:49 pmDunno, but if the 130+ tons one SLS will lift are instead lifted with FH's, you get up to $750mn saved from the Atlantic to work with.And the TMI for an FH reusable is about 11.7 long tons to go by past history (I don't know where you are getting 4,900kg from), so you get to keep the rockets. I'm generously (to ULA) calling the per launch FH cost to be $250mn per, where the quoted cost is $90mn.A deep space tug/stage is required anyway.SpaceX quotes the FH at than $90m up to 8000kg to GTO, suggesting that that is the cutoff point for triple core landings. Given that that is roughly the same as expendable F9, a similar TMI capacity as expendable F9 should be expected - F9 can do 4,020kg to TMI. So why do you think it can do 11.7 long tons?
(16,800kg to Mars expendable X 0.7 for reusability X 2.2 for kg to lbs conversion) / 2204 for pounds to long tons =~ 11.7
Quote from: tdperk on 08/11/2017 07:29 pm(16,800kg to Mars expendable X 0.7 for reusability X 2.2 for kg to lbs conversion) / 2204 for pounds to long tons =~ 11.7From (ugh) https://en.wikipedia.org/wiki/TonBritish [long] ton is 2240 lbsUS [short] ton is 2000 lbsMetric (seems to be the primary measure used for rocket capabilities) ton [tonne, MT] is 2204.6 lbsTo convert from kg to mT, just divide by 1k -e
Quote from: edkyle99 on 08/11/2017 06:23 pmQuote from: tdperk on 08/11/2017 05:19 pm" The LEO-rendezvous Falcon ... is actual cargo. " <-- Nothing you have said here is true and relevant, as you presume the use of non-optimal architectures which are easily avoided. What is the "optimal" alternative architecture?The one that gets the job done for the least $.
That could very well be SLS/Orion. NASA's goal is $1.5 billion per year for one to two SLS/Orion launches. The fully-recoverable Falcon Heavy/Dragon cost for the ten flights we've been discussing would exceed $1.8 billion. - Ed Kyle
Metric (seems to be the primary measure used for rocket capabilities) ton [tonne, t (SI), MT (sic)] is 2204.6 lbs
Quote from: edkyle99 on 08/12/2017 05:45 amThat could very well be SLS/Orion. NASA's goal is $1.5 billion per year for one to two SLS/Orion launches. The fully-recoverable Falcon Heavy/Dragon cost for the ten flights we've been discussing would exceed $1.8 billion. - Ed KyleHow do you get to $180 million per 3 core reusable FH flight? No way that would be more than $100 million with a healthy profit.Edit: added 3 core reusable
Quote from: tdperk on 08/11/2017 06:49 pmQuote from: edkyle99 on 08/11/2017 06:23 pmQuote from: tdperk on 08/11/2017 05:19 pm" The LEO-rendezvous Falcon ... is actual cargo. " <-- Nothing you have said here is true and relevant, as you presume the use of non-optimal architectures which are easily avoided. What is the "optimal" alternative architecture?The one that gets the job done for the least $. That could very well be SLS/Orion. NASA's goal is $1.5 billion per year for one to two SLS/Orion launches. The fully-recoverable Falcon Heavy/Dragon cost for the ten flights we've been discussing would exceed $1.8 billion. - Ed Kyle
Quote from: guckyfan on 08/12/2017 06:10 amQuote from: edkyle99 on 08/12/2017 05:45 amThat could very well be SLS/Orion. NASA's goal is $1.5 billion per year for one to two SLS/Orion launches. The fully-recoverable Falcon Heavy/Dragon cost for the ten flights we've been discussing would exceed $1.8 billion. - Ed KyleHow do you get to $180 million per 3 core reusable FH flight? No way that would be more than $100 million with a healthy profit.Edit: added 3 core reusableI am comparing cost of launch vehicle and payload. - Ed Kyle
Quote from: edkyle99 on 08/12/2017 12:26 pmQuote from: guckyfan on 08/12/2017 06:10 amQuote from: edkyle99 on 08/12/2017 05:45 amThat could very well be SLS/Orion. NASA's goal is $1.5 billion per year for one to two SLS/Orion launches. The fully-recoverable Falcon Heavy/Dragon cost for the ten flights we've been discussing would exceed $1.8 billion. - Ed KyleHow do you get to $180 million per 3 core reusable FH flight? No way that would be more than $100 million with a healthy profit.Edit: added 3 core reusableI am comparing cost of launch vehicle and payload. - Ed Kyle You're comparing 1 Orion to 10 Dragons?
But three FH flights duplicate one SLS for at most half the cost. 1/4 the cost is plausible.And no, there has to be something smart enough and with enough fuel or refuel-able on orbit at the top of one rocket. Your presuming otherwise is you presuming sub-optimal architectures.
Quote from: tdperk on 08/12/2017 03:28 pmBut three FH flights duplicate one SLS for at most half the cost. 1/4 the cost is plausible.And no, there has to be something smart enough and with enough fuel or refuel-able on orbit at the top of one rocket. Your presuming otherwise is you presuming sub-optimal architectures.The Falcon Heavy upper stage batteries die after several hours at most and there is no means for recharging them. The stage has no ability to rendezvous or dock with other orbiting objects. There is no auto docking system for the stage. There is no propellant transfer system once docked. You pretend that all of these non-existing capabilities have no cost when, in fact, the cost to develop and test and fly such systems would be quite large. Dragon can fly in space, rendezvous, and dock, making it a good surrogate for such costs. - Ed Kyle