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#140 by ThePonjaX on 03 Aug, 2019 15:38
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"SpaceX plans to launch the Starship/Super Heavy up to 24 times per year from LC-39A. A static fire test would be conducted on each stage prior to each launch."
I think this number can surpassed sooner than we tough, when the refueling in orbit is in place you need:
1 launch for the cargo + 5 launches for fuel ( can be more) = 6 launches just for 1 moon mission.
So in an extreme case 4 missions to the moon you already have 24 launches in a year.
It's going to be interesting the frequency of launches to refill an Starship to the moon: 1 by week ? 1 every 3 days? Maybe on that was Elon thinking when he wanted to relaunch a F9 after just 24 hours.
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#141 by ZachF on 03 Aug, 2019 15:48
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"SpaceX plans to launch the Starship/Super Heavy up to 24 times per year from LC-39A. A static fire test would be conducted on each stage prior to each launch."
Yes, but it also says:
"The Starship and Super Heavy would exceed the lift capabilities of the Falcon Heavy. Due to the higher lift capability, Starship/Super Heavy could launch more payloads and reduce the overall launch cadence when compared to Falcon 9 and Falcon Heavy. This would increase the cost effectiveness of the space industry."
Sounds like STS, or Titan IV, or EELV. Fewer launches, more stuff on each. Initial claims of cost-effectiveness that didn't pan out in those cases.
- Ed Kyle
Starlink will be the majority of SpaceX's launches in the near future. -
#142 by ZachF on 03 Aug, 2019 15:52
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"SpaceX plans to launch the Starship/Super Heavy up to 24 times per year from LC-39A. A static fire test would be conducted on each stage prior to each launch."
I think this number can surpassed sooner than we tough, when the refueling in orbit is in place you need:
1 launch for the cargo + 5 launches for fuel ( can be more) = 6 launches just for 1 moon mission.
So in an extreme case 4 missions to the moon you already have 24 launches in a year.
It's going to be interesting the frequency of launches to refill an Starship to the moon: 1 by week ? 1 every 3 days? Maybe on that was Elon thinking when he wanted to relaunch a F9 after just 24 hours.
I have a feeling the tanker flights will take place from Boca Chica, my guess:
Manned: Florida
Cargo: both (probably GTO from BC, LEO from both, and polar from florida with a dogleg?)
Tankers: BC
I also suspect that if there is a manned mission that needs a full refill, they will fill up a tanker first and have it waiting for them. -
#143 by spacenut on 03 Aug, 2019 15:54
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After Starlink, NASA will begin to see the enormous capability of Starship vs their own SLS. Then NASA and satellite manufacturers will design larger payloads. Large space stations and the beginnings of an O'Neil colony, or permanent moon base. So much opens up. Remember Starship is for mars colonization. Some people still can't wrap their brains around what is happening before our eyes. I just hope government red tape don't slow down SpaceX's progress.
Even today's rockets can launch larger payloads than the rockets of the 60's until Titan III an IV came along. Even Saturn IB wasn't used that much back then. Now F9 can launch Saturn IB sized payloads to LEO routinely.
Face it rockets like Starship and New Glenn will deliver heavier payloads to orbit or beyond. Government red tape has to catch up with the times.
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#144 by joek on 03 Aug, 2019 16:03
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... I think this number can surpassed sooner than we tough, when the refueling in orbit is in place you need:
1 launch for the cargo + 5 launches for fuel ( can be more) = 6 launches just for 1 moon mission. ...
Might want to work it from the other direction: How many refueling flights does it take to get an empty SS to the lunar surface and back to Earth surface? How much additional payload mass does each additional tanker get you? What are the likely payload mass requirements? That will determine the number of tanker flights.
Think @speedevil did some related work in another thread, which I cannot find at the moment. -
#145 by ZachF on 03 Aug, 2019 16:04
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"SpaceX plans to launch the Starship/Super Heavy up to 24 times per year from LC-39A. A static fire test would be conducted on each stage prior to each launch."
I think this number can surpassed sooner than we tough, when the refueling in orbit is in place you need:
1 launch for the cargo + 5 launches for fuel ( can be more) = 6 launches just for 1 moon mission.
So in an extreme case 4 missions to the moon you already have 24 launches in a year.
It's going to be interesting the frequency of launches to refill an Starship to the moon: 1 by week ? 1 every 3 days? Maybe on that was Elon thinking when he wanted to relaunch a F9 after just 24 hours.
Don't forget, LC-39 number doesn't include any Boca Chica launches.
I suspect most tanker and GTO flights will take place from Boca Chica. Lower latitude of BC would increase GTO payload by around 10%. -
#146 by ZachF on 03 Aug, 2019 16:13
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After Starlink, NASA will begin to see the enormous capability of Starship vs their own SLS. Then NASA and satellite manufacturers will design larger payloads. Large space stations and the beginnings of an O'Neil colony, or permanent moon base. So much opens up. Remember Starship is for mars colonization. Some people still can't wrap their brains around what is happening before our eyes. I just hope government red tape don't slow down SpaceX's progress.
Even today's rockets can launch larger payloads than the rockets of the 60's until Titan III an IV came along. Even Saturn IB wasn't used that much back then. Now F9 can launch Saturn IB sized payloads to LEO routinely.
Face it rockets like Starship and New Glenn will deliver heavier payloads to orbit or beyond. Government red tape has to catch up with the times.
I'm curious as to how satellite designs change when saving every pound isn't as important.
Ultimately, satellite operators buy a service capacity for money.
For instance, what kind of service capacity could a satellite operator buy with $300m if they have a launch system can now put 20+ tonnes to GTO for <$25m, vs $60m for 5.5tonnes now? Do the satellites use 'dumber', much less-mass sensitive designs? -
#147 by spacenut on 03 Aug, 2019 16:27
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Also Boca Chica is closer to Natural gas production and pipelines. Maybe somewhat lower bulk prices for methane than Florida. I remember when a few years back, they ran a large offshore natural gas pipeline along the gulf coast to central Florida for power production since central Florida was growing so fast. A huge percentage of power production in Texas and Florida is natural gas power plant.
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#148 by mclumber1 on 03 Aug, 2019 17:21
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"SpaceX plans to launch the Starship/Super Heavy up to 24 times per year from LC-39A. A static fire test would be conducted on each stage prior to each launch."
I think this number can surpassed sooner than we tough, when the refueling in orbit is in place you need:
1 launch for the cargo + 5 launches for fuel ( can be more) = 6 launches just for 1 moon mission.
So in an extreme case 4 missions to the moon you already have 24 launches in a year.
It's going to be interesting the frequency of launches to refill an Starship to the moon: 1 by week ? 1 every 3 days? Maybe on that was Elon thinking when he wanted to relaunch a F9 after just 24 hours.
Manned moon missions would ideally (in my mind) go like this: Launch 1 tanker into orbit. Launch subsequent tankers to fill up the tanker that is already in orbit. Once the tanker is full, launch the manned Starship into orbit, where the fuel will be transferred from the tanker to the Starship. -
#149 by Ulysses S on 04 Aug, 2019 19:40
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I see it like this Starship first, then tankers. When Starship is fueled another tanker full to run in parallel with Starship. Two Falcon 9s with Dragons and a crew of seven each from 39a and 40 to dock and board Starship. That gives you 14 Troopers with carry on luggage and a quick turn around fuel supply and will leave a Tanker on the surface after a month stay.
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#150 by Dave G on 04 Aug, 2019 19:51
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Manned moon missions would ideally (in my mind) go like this: Launch 1 tanker into orbit. Launch subsequent tankers to fill up the tanker that is already in orbit. Once the tanker is full, launch the manned Starship into orbit, where the fuel will be transferred from the tanker to the Starship.
That would require SpaceX to build 2 tankers for each Starship.
Remember, with BFR, the major expense for SpaceX will be building each Starship, tanker, and booster.
With full and rapid reuse, the operating expense for each launch is less than Falcon 1, let alone Falcon 9.
So to accelerate the schedule, it may be better to build the minimum practical number of vehicles, at least initially.
With this in mind, another solution would be to build just 1 tanker for each Starship.
Launch Starship first, then launch a single tanker 5 times to refill it.
That's how I'm interpreting the slide below.
Note: Elon said the initial tanker will just be an empty cargo Starship.
The eventual purpose-built tanker will be mass-optimized, possibly requiring only 4 tanker launches, as shown.
For the initial cargo missions, there's no need to rush between the initial Starship launch and TMI.
For eventual manned missions, I suspect they'll get the turn-around time at the launch pad down to a few hours.
With this in mind, how soon could they get the same tanker back to the pad after refilling Earth orbit?
Within 24 hours? If so the crew would have to hang out in Earth orbit for around 4 days. Not a deal-breaker.
I'm assuming the first tanker can launch a few hours after Starship.
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#151 by spacenut on 04 Aug, 2019 19:51
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I thought somewhere on here it was mentioned, only one tanker for a loop around the moon, and 2 or 3 for landing and return. Mars would take 6 tankers to fully fuel transport and slow down and land on Mars. Moon would need less fuel due to shorter distance and lower gravity.
I do like the idea of fueling an orbital tanker (like a fuel depot), then launch a human/cargo mission to the moon and or Mars by only docking once with the human cargo and fuel up. Not 6 dockings and fuelings while people on board wait for days tanking. Just launch, dock once, fuel up, and go. Less time in route. -
#152 by Dave G on 04 Aug, 2019 19:56
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... Two Falcon 9s with Dragons and a crew of seven each from 39a and 40 to dock and board Starship. That gives you 14 Troopers with carry on luggage and a quick turn around fuel supply and will leave a Tanker on the surface after a month stay.
Remember, SpaceX intends to stop building Falcon 9 and Dragon, and focus the whole company on building BFR.
BFR will do everything Falcon 9 and Dragon does today, with a cost per launch less than Falcon 1, let alone Falcon 9. -
#153 by DistantTemple on 04 Aug, 2019 20:01
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Yes but he mentioned USGOV employees. (Troopers) There may well be some use of D2 if the agencies are cautious of having no escape system for launch etc. - initially.... Two Falcon 9s with Dragons and a crew of seven each from 39a and 40 to dock and board Starship. That gives you 14 Troopers with carry on luggage and a quick turn around fuel supply and will leave a Tanker on the surface after a month stay.
Remember, SpaceX intends to stop building Falcon 9 and Dragon, and focus the whole company on building BFR.
BFR will do everything Falcon 9 and Dragon does today, with a cost per launch less than Falcon 1, let alone Falcon 9. -
#154 by Dave G on 04 Aug, 2019 20:03
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I thought somewhere on here it was mentioned, only one tanker for a loop around the moon, and 2 or 3 for landing and return. Mars would take 6 tankers to fully fuel transport and slow down and land on Mars. Moon would need less fuel due to shorter distance and lower gravity.
I don't think SpaceX has said anything definite on this.
I've only seen the attached general slide showing that refilling would occur in a highly elliptical orbit (not LEO).I do like the idea of fueling an orbital tanker (like a fuel depot), then launch a human/cargo mission to the moon and or Mars by only docking once with the human cargo and fuel up. Not 6 dockings and fuelings while people on board wait for days tanking. Just launch, dock once, fuel up, and go. Less time in route.
Musk doesn't seem to like the fuel depot idea. He's mentioned this more than once.
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#155 by Dave G on 04 Aug, 2019 20:16
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Yes but he mentioned USGOV employees. (Troopers) There may well be some use of D2 if the agencies are cautious of having no escape system for launch etc. - initially.... Two Falcon 9s with Dragons and a crew of seven each from 39a and 40 to dock and board Starship. That gives you 14 Troopers with carry on luggage and a quick turn around fuel supply and will leave a Tanker on the surface after a month stay.
Remember, SpaceX intends to stop building Falcon 9 and Dragon, and focus the whole company on building BFR.
BFR will do everything Falcon 9 and Dragon does today, with a cost per launch less than Falcon 1, let alone Falcon 9.
To be clear, the initial NASA lunar Starship missions will be for cargo, not crew.
I suspect it will be quite a while before NASA is comfortable putting their crew on Starship, regardless of the mode.
By then, I suspect SpaceX will have flown several private manned missions, similar to dearMoon.
With this in mind, it's very hard to predict how crewed NASA Starship missions will play out.
If SpaceX proves Starship is crew-capable with several private missions, NASA may be willing to take the risk. -
#156 by meberbs on 04 Aug, 2019 20:19
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I thought somewhere on here it was mentioned, only one tanker for a loop around the moon, and 2 or 3 for landing and return. Mars would take 6 tankers to fully fuel transport and slow down and land on Mars. Moon would need less fuel due to shorter distance and lower gravity.
I don't think SpaceX has said anything definite on this.
I've only seen the attached general slide showing that refilling would occur in a highly elliptical orbit (not LEO).I do like the idea of fueling an orbital tanker (like a fuel depot), then launch a human/cargo mission to the moon and or Mars by only docking once with the human cargo and fuel up. Not 6 dockings and fuelings while people on board wait for days tanking. Just launch, dock once, fuel up, and go. Less time in route.
Musk doesn't seem to like the fuel depot idea. He's mentioned this more than once.
I am not sure where you are getting that from , he has recently posted a tweet implying that eventually depots will make sense. In the short term, it will be ship to ship, but the proposed scenario is exactly that: a ship to ship transfer. It wouldn't make sense at all to do that for unmanned missions, and Musk may currently expect that by the time manned flights happen launch cadence will be sufficient that there is little point in the architecture spacenut is discussing. But if they get around to manned flights, and the refueling period still takes a couple weeks, I haven't seen any indication that such a plan would be off the table.
https://twitter.com/elonmusk/status/1156970909258829824 -
#157 by joek on 04 Aug, 2019 20:23
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...
Musk doesn't seem to like the fuel depot idea. He's mentioned this more than once.
Unclear if Musk's resistance to "depot" is to a dedicated-different-hardware depot vs. a SS tanker-as-depot (temporary or semi-permanent). Can understand his resistance to the former, which is how depots are framed in many architectures. Clarification needed to understand his position on the latter. Might be as simple as Musk wanting to ensure it is clear that SpaceX will build tankers, not depots.[1]
[1] edit: For the foreseeable future; and they will be specific to SS not general purpose depots. -
#158 by gongora on 04 Aug, 2019 21:24
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Shortly before the tweet linked above Elon had this one:
https://twitter.com/elonmusk/status/1156671312716111872 -
#159 by RobLynn on 04 Aug, 2019 21:28
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To me this report provides a pretty strong indication that SpaceX will progressively move towards offshore flight operations on purpose built ships. The noise issues of frequent flights make land based operations untenable in long term, and range safety issues are greatly magnified by operations close to population and overland airspace while point to point operations always had to be off shore, not to mention the safety related inability to launch over-land that prevents use of Boca Chica or Canaveral SS/SH launches for polar or sun synchronous orbits. so after the SS/SH system has been debugged through probably first couple of years of land based operations I expect there will be larger optimised offshore launch ships built.
Added benefit that optimal downrange landing of SH provides a 10's of percent increase in payload to orbit compared to RTLS.