SLS Manifest Options:The decision to keep SLS in its Block 1 configuration and launching off ML-1 deep into the 2020s now leaves NASA with some decision points.At one stage, NASA was expecting to use the Block 1 with DCSS configuration just once, on the EM-1 mission. Now it is expected it will return to the previous plan of mirroring EM-1 (uncrewed Orion) and EM-2 (crewed Orion) on matching missions and rocket configurations. However, due to Orion readiness, it is unlikely both missions will close the previous multi-year gap by any notable margin.What is becoming an option for bridging that gap between flights is using SLS to launch the flagship Europa Clipper mission in 2022. Originally, Europa Clipper was to use a Block 1B SLS to allow the EUS to be flight-proven before launching a crewed mission. NASA then decided that a crew could launch on the first Block 1B on a non-flight proven EUS.Now, with Block 1B many years away, NASA is looking at launching the Europa Clipper mission on a Block 1 SLS, a flight sometimes referred to as SM-1 (Science Mission -1) on documentation. Other documentation confusingly calls it EM-2, likely in some cheeky way of satisfying politically-driven schedules for SLS to fly “EM-2” by a certain date.Inquiries are taking place into the loss of mission performance per Europa Clipper flying on the Block 1 versus Block 1B SLS. A major selling point of flying the Europa mission on an SLS Block 1B was using the EUS to shave many years off the transit time compared to “currently” available rocket options at the time the mission’s launch vehicle was first discussed.Block 1 performance capability for Europa Clipper may push the launch vehicle discussion into an uncomfortable debate, where SpaceX’s Falcon Heavy could force NASA’s hand based on the gulf of vehicle costs. A brand-new Falcon Heavy for a high priority science mission would cost just over $100 million, whereas the latest estimates for SLS put the per-mission cost anywhere between $500 million (from NASA in 2013) to a range between $1.5 – $2.5 billion (conservative industry estimates in December 2017).
Quote from Chris' latest SLS article today (bolding mine).Quote from: Chris BergenBlock 1 performance capability for Europa Clipper may push the launch vehicle discussion into an uncomfortable debate, where SpaceX’s Falcon Heavy could force NASA’s hand based on the gulf of vehicle costs. A brand-new Falcon Heavy for a high priority science mission would cost just over $100 million, whereas the latest estimates for SLS put the per-mission cost anywhere between $500 million (from NASA in 2013) to a range between $1.5 – $2.5 billion (conservative industry estimates in December 2017).Quite a difference in LV cost. With continued SLS delays and such a lower cost for FH, SpaceX's chances for launching Europa Clipper on FH just got better. Who knows, she could even go up on BFR.
Block 1 performance capability for Europa Clipper may push the launch vehicle discussion into an uncomfortable debate, where SpaceX’s Falcon Heavy could force NASA’s hand based on the gulf of vehicle costs. A brand-new Falcon Heavy for a high priority science mission would cost just over $100 million, whereas the latest estimates for SLS put the per-mission cost anywhere between $500 million (from NASA in 2013) to a range between $1.5 – $2.5 billion (conservative industry estimates in December 2017).
Quote from: TomH on 04/23/2018 11:48 pmQuote from Chris' latest SLS article today (bolding mine).Quote from: Chris BergenBlock 1 performance capability for Europa Clipper may push the launch vehicle discussion into an uncomfortable debate, where SpaceX’s Falcon Heavy could force NASA’s hand based on the gulf of vehicle costs. A brand-new Falcon Heavy for a high priority science mission would cost just over $100 million, whereas the latest estimates for SLS put the per-mission cost anywhere between $500 million (from NASA in 2013) to a range between $1.5 – $2.5 billion (conservative industry estimates in December 2017).Quite a difference in LV cost. With continued SLS delays and such a lower cost for FH, SpaceX's chances for launching Europa Clipper on FH just got better. Who knows, she could even go up on BFR.The thing is, NASA could very likely fund the development of a cryogenic Raptor upper stage for Falcon and still get the Clipper to Europa faster and several times cheaper than SLS w/ ICPS.
Hans' NEAF 2018 talk had some quasi-updated specs and details for Falcon Heavy, and they of course contradict what's on SpaceX's website Quote• Falcon Heavy: 20t to GTO & 13t to TMI (website: 26.7t & 16.8t)...(snip)o “[Crossfeed] may be introduced a bit later on”
• Falcon Heavy: 20t to GTO & 13t to TMI (website: 26.7t & 16.8t)...(snip)o “[Crossfeed] may be introduced a bit later on”
Quote from: vaporcobra on 04/23/2018 11:24 pmHans' NEAF 2018 talk had some quasi-updated specs and details for Falcon Heavy, and they of course contradict what's on SpaceX's website Quote• Falcon Heavy: 20t to GTO & 13t to TMI (website: 26.7t & 16.8t)...(snip)o “[Crossfeed] may be introduced a bit later on”That's a bit significant. Any elaboration on that?
Quote from: vaporcobra on 04/24/2018 01:02 amQuote from: TomH on 04/23/2018 11:48 pmQuote from Chris' latest SLS article today (bolding mine).Quote from: Chris BergenBlock 1 performance capability for Europa Clipper may push the launch vehicle discussion into an uncomfortable debate, where SpaceX’s Falcon Heavy could force NASA’s hand based on the gulf of vehicle costs. A brand-new Falcon Heavy for a high priority science mission would cost just over $100 million, whereas the latest estimates for SLS put the per-mission cost anywhere between $500 million (from NASA in 2013) to a range between $1.5 – $2.5 billion (conservative industry estimates in December 2017).Quite a difference in LV cost. With continued SLS delays and such a lower cost for FH, SpaceX's chances for launching Europa Clipper on FH just got better. Who knows, she could even go up on BFR.The thing is, NASA could very likely fund the development of a cryogenic Raptor upper stage for Falcon and still get the Clipper to Europa faster and several times cheaper than SLS w/ ICPS.What ever happened to the Raptor upper stage concept? I know the Air Force paid for some of its development, but I haven't heard anything about it since 2015 or 2016.Are they just waiting on BFR, or maybe stock FH is already enough?
Quote from: IanThePineapple on 04/24/2018 01:07 amQuote from: vaporcobra on 04/24/2018 01:02 amQuote from: TomH on 04/23/2018 11:48 pmQuote from Chris' latest SLS article today (bolding mine).Quote from: Chris BergenBlock 1 performance capability for Europa Clipper may push the launch vehicle discussion into an uncomfortable debate, where SpaceX’s Falcon Heavy could force NASA’s hand based on the gulf of vehicle costs. A brand-new Falcon Heavy for a high priority science mission would cost just over $100 million, whereas the latest estimates for SLS put the per-mission cost anywhere between $500 million (from NASA in 2013) to a range between $1.5 – $2.5 billion (conservative industry estimates in December 2017).Quite a difference in LV cost. With continued SLS delays and such a lower cost for FH, SpaceX's chances for launching Europa Clipper on FH just got better. Who knows, she could even go up on BFR.The thing is, NASA could very likely fund the development of a cryogenic Raptor upper stage for Falcon and still get the Clipper to Europa faster and several times cheaper than SLS w/ ICPS.What ever happened to the Raptor upper stage concept? I know the Air Force paid for some of its development, but I haven't heard anything about it since 2015 or 2016.Are they just waiting on BFR, or maybe stock FH is already enough?Stock FH is very likely not capable of competing 1:1 with DIVH/Atlas 551 thanks to Centaur. Direct GEO insertion and interplanetary stuff is where FH still falls short as a result of upper stage inefficiency. As for the Rapter US, I haven't heard anything. The most recent RFP (the one for entire new EELVs) basically only discussed the USAF's Raptor funding as an effort to development propulsion systems, not a replacement upper stage. Perhaps SpaceX's proposal will be a RUS for Block 5 F9 and FH, if they don't push for BFR.
Quote from: vaporcobra on 04/24/2018 01:33 amAs for the Rapter US, I haven't heard anything. The most recent RFP (the one for entire new EELVs) basically only discussed the USAF's Raptor funding as an effort to development propulsion systems, not a replacement upper stage. Perhaps SpaceX's proposal will be a RUS for Block 5 F9 and FH, if they don't push for BFR.I think a RUS could also be used with Cargo BFR as a third stage, similar to the Shuttle-Centaur concept.
As for the Rapter US, I haven't heard anything. The most recent RFP (the one for entire new EELVs) basically only discussed the USAF's Raptor funding as an effort to development propulsion systems, not a replacement upper stage. Perhaps SpaceX's proposal will be a RUS for Block 5 F9 and FH, if they don't push for BFR.
The BFS is a Raptor upper stage!
Quote from: CuddlyRocket on 04/24/2018 03:39 amThe BFS is a Raptor upper stage!But not a third stage. A third stage would make a fine addition for probes to the outer solar system avoiding expending a BFS for that purpose.
Raptor might be a bit high thrust.Even if it can throttle to 60 tons, that's quite a high G at the end of a burn with a total 150 ton payload mass into LEO.
Quite a difference in LV cost. With continued SLS delays and such a lower cost for FH, SpaceX's chances for launching Europa Clipper on FH just got better. Who knows, she could even go up on BFR.
The thing is, NASA could very likely fund the development of a cryogenic Raptor upper stage for Falcon 9/Heavy and still get Clipper to Europa faster and several times cheaper than SLS w/ ICPS.
...Stock FH is very likely not capable of competing 1:1 with DIVH/Atlas 551 thanks to Centaur. Direct GEO insertion and interplanetary stuff is where FH still falls short as a result of upper stage inefficiency. As for the Rapter US, I haven't heard anything. The most recent RFP (the one for entire new EELVs) basically only discussed the USAF's Raptor funding as an effort to development propulsion systems, not a replacement upper stage. Perhaps SpaceX's proposal will be a RUS for Block 5 F9 and FH, if they don't push for BFR.
Quote from: TaurusLittrow on 04/23/2018 08:33 pmThree years to human rate ICPS and make Orion suitable for astronauts!?Where does that information come from?Quote from: butters on 04/24/2018 12:15 amIt's possible to interpret the prolonged delay of EUS as evidence that perhaps the software issues are predominantly related to EUS, and that the software for the rest of SLS is more mature because "heritage hardware."EUS is still being designed. Any software issues are more likely due to elements that are being built now.For those interested, Block I payload to Europa is only 2.9 t, compared to 8.1 t for Block IB. I estimate FH expendable payload for Europa (for 6,783 m/s delta-V from LEO) to be 6.5 t!
Three years to human rate ICPS and make Orion suitable for astronauts!?
It's possible to interpret the prolonged delay of EUS as evidence that perhaps the software issues are predominantly related to EUS, and that the software for the rest of SLS is more mature because "heritage hardware."
Quote from: MATTBLAK on 04/24/2018 06:19 amSteven: do you happen to know how much Vulcan/Centaur V with 6x solid boosters could throw at Jupiter?I modified the Falcon Heavy program and made a few guestimates of the Vulcan second stage. From the drawing, I got a propellant mass of 56.2 t and a dry mass of 5.0 t. Extrapolating using RL10C-1 engines, 34.9 t LEO payload and 7.1 t GEO payload, I got only a 964 kg payload to Europa! Need to either use a solid third stage, flyby's or refuelling the second stage to get better performance.Attached is the program I used to calculate performance.Note that the first version I posted overestimated the Vulcan second stage propellant and dry mass, giving only a 105 kg payload mass to Europa.
Steven: do you happen to know how much Vulcan/Centaur V with 6x solid boosters could throw at Jupiter?
Quote from: Kansan52 on 04/23/2018 11:31 pmWill the Block 5 version come closer to the web site numbers?My assumption is that Hans' 20t and 13t figures are for missions that expend the center core, per Musk's recent tweets on the subject. It's a long shot from "~10%," but Musk issss known for his optimism... QuoteSide boosters landing on droneships & center expended is only ~10% performance penalty vs fully expended. Cost is only slightly higher than an expended F9, so around $95M.
Will the Block 5 version come closer to the web site numbers?
Side boosters landing on droneships & center expended is only ~10% performance penalty vs fully expended. Cost is only slightly higher than an expended F9, so around $95M.
Quote from: TomH on 04/23/2018 11:48 pmQuote from Chris' latest SLS article today (bolding mine).Quote from: Chris BergenBlock 1 performance capability for Europa Clipper may push the launch vehicle discussion into an uncomfortable debate, where SpaceX’s Falcon Heavy could force NASA’s hand based on the gulf of vehicle costs. A brand-new Falcon Heavy for a high priority science mission would cost just over $100 million, whereas the latest estimates for SLS put the per-mission cost anywhere between $500 million (from NASA in 2013) to a range between $1.5 – $2.5 billion (conservative industry estimates in December 2017).Quite a difference in LV cost. With continued SLS delays and such a lower cost for FH, SpaceX's chances for launching Europa Clipper on FH just got better. Who knows, she could even go up on BFR.The thing is, NASA could very likely fund the development of a cryogenic Raptor upper stage for Falcon 9/Heavy and still get Clipper to Europa faster and several times cheaper than SLS w/ ICPS.
Stock FH is very likely not capable of competing 1:1 with DIVH/Atlas 551 thanks to Centaur. Direct GEO insertion and interplanetary stuff is where FH still falls short as a result of upper stage inefficiency.
Quote from: vaporcobra on 04/24/2018 01:02 amQuote from: TomH on 04/23/2018 11:48 pmQuote from Chris' latest SLS article today (bolding mine).Quote from: Chris BergenBlock 1 performance capability for Europa Clipper may push the launch vehicle discussion into an uncomfortable debate, where SpaceX’s Falcon Heavy could force NASA’s hand based on the gulf of vehicle costs. A brand-new Falcon Heavy for a high priority science mission would cost just over $100 million, whereas the latest estimates for SLS put the per-mission cost anywhere between $500 million (from NASA in 2013) to a range between $1.5 – $2.5 billion (conservative industry estimates in December 2017).Quite a difference in LV cost. With continued SLS delays and such a lower cost for FH, SpaceX's chances for launching Europa Clipper on FH just got better. Who knows, she could even go up on BFR.The thing is, NASA could very likely fund the development of a cryogenic Raptor upper stage for Falcon 9/Heavy and still get Clipper to Europa faster and several times cheaper than SLS w/ ICPS.No, just stop.
[Jim]Stop daydreaming.[/Jim]