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#1160 by Space Ghost 1962 on 18 May, 2017 16:45
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It's not the capsule that limits SX RD and lunar free return. Other things do.
First of them is enough experience with FH.
Suggest you time FH integration and time to next FH flight. When these become predictable/effective, that limit may go.
Next up, Dragon 2 demonstration of a week of ECLSS operation (in space?).
Integration of deep space comms.
Discussion of mission contingencies. -
#1161 by jak Kennedy on 18 May, 2017 17:00
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some of the last comments about the window got me thinking. Won't they try and line up the window so that a large amount of the moon is in daylight as they swing by? It would suck to go all that way if you can not see much.
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#1162 by Bynaus on 18 May, 2017 17:06
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The Moon is always half in daylight...
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#1163 by kch on 18 May, 2017 17:25
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#1164 by saliva_sweet on 18 May, 2017 17:32
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Note: the linked article on space.com was written by someone who was banned from this forum for "having an agenda" with regards to SpaceX.
I don't know, but I think that's ridiculous. I don't think he has an agenda. He's just a bitter jerk (like me). -
#1165 by envy887 on 18 May, 2017 17:39
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The Moon is always half in daylight...
... But the point of closest approach is dictated by your approach from Earth. Since it's a flyby, the passengers will only get to see a small part of the Moon surface close up, probably the far side towards the leading edge. I'm sure they will want that part sunlit. -
#1166 by jpo234 on 18 May, 2017 18:09
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The Moon is always half in daylight...
Nit picking: not during a Lunar eclipse. -
#1167 by manoweb on 18 May, 2017 18:19
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some of the last comments about the window got me thinking. Won't they try and line up the window so that a large amount of the moon is in daylight as they swing by? It would suck to go all that way if you can not see much.
I understand what you mean here but you have a good window at least once a month, compared to a much larger interval for a Mars mission... if there is a delay, just go a month later no? -
#1168 by clongton on 19 May, 2017 00:54
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The Moon is always half in daylight...
Nit picking: not during a Lunar eclipse.
That's called nightlight (ducking now). -
#1169 by deruch on 19 May, 2017 02:02
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From the new GAO report http://www.gao.gov/assets/690/684626.pdf we learn that SpaceX plans to certify the commercial crew vehicles in Q3/2018 (see page 47). This is awfully close to the proposed date for the Grey/Silver Dragon mission.
From a technical standpoint, no. There's no reason why they would have to wait for certification before the lunar mission. At least, not assuming that they've satisfied themselves and their customers on their technical proficiency. But, from a business standpoint, I think yes. I would be very surprised to learn that they hadn't sold the mission as being flown on a capsule certified by NASA (though not for this mission, just certified for NASA HSF missions to ISS). Also, and maybe more importantly, there's the question of capsule production. Where is SpaceX getting the Dragon capsule for this mission? Right now, according to latest public info I have seen, they have 4 in production. One each for the 2 demonstration missions for CC, then they've sold 2 Post-Certification Missions and presumably have started production on those. Also, they need to produce cargo-variant Dragon 2s for CRS2. If they are reusing a "flight-proven" capsule this is much less of an issue.
Is CCP certification on the critical path for Grey Dragon? Could SpaceX launch Grey Dragon before CCP certification? -
#1170 by meekGee on 19 May, 2017 02:10
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There is no hard window here, so it is virtually certain they will slide the mission to the right until the required boxes are checked off (crewed flight, certification, confidence in FH as a launcher).
It's pretty hard to use "there is no hard window here" and "they will slide the mission to the right" in the same sentence. Aren't the 2 statements mutually exclusive?
Hard window as in "launch window to Mars". If you miss the original date, you can pick another one without having to wait long for "the stars to align".
I normally wouldn't, but since you nit picked, I'll reverse nit:
The idiom is "waiting for planets to align", and for a reason....
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#1171 by TomH on 19 May, 2017 03:09
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The Moon is always half in daylight...
Your tag line states that you are a planetary scientist??? Luna is not always half in daylight! Can you say...........lunar eclipse? -
#1172 by obi-wan on 19 May, 2017 03:28
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some of the last comments about the window got me thinking. Won't they try and line up the window so that a large amount of the moon is in daylight as they swing by? It would suck to go all that way if you can not see much.
I understand what you mean here but you have a good window at least once a month, compared to a much larger interval for a Mars mission... if there is a delay, just go a month later no?
The Apollo limitation of monthly launch windows was driven by the constraint to land shortly after lunar dawn at the landing site, so you're looking down-sun and there are elongated shadows to show obstacles in the landing field. If you're just doing a fly-by, you could launch almost any day - and with a preliminary parking orbit in LEO, with wide launch windows. -
#1173 by manoweb on 19 May, 2017 05:21
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But, from a business standpoint, I think yes. I would be very surprised to learn that they hadn't sold the mission as being flown on a capsule certified by NASA
Unless the customer is internal to SpaceX, and has access to data that make a NASA certification less relevant -
#1174 by jpo234 on 19 May, 2017 07:04
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I normally wouldn't, but since you nit picked, I'll reverse nit:
The idiom is "waiting for planets to align", and for a reason....
Touché!
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#1175 by Bynaus on 19 May, 2017 07:43
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The Moon is always half in daylight...
Your tag line states that you are a planetary scientist??? Luna is not always half in daylight! Can you say...........lunar eclipse?
Jup, that is a (mostly) correct and witty comment - although I was obviously talking of the general situation here. But if you want to take nit-picking a step further, the Moon is still half in daylight even during a lunar eclipse: it's just that the sunlight that still reaches its surface has been refracted, and strongly reduceced in total intensity by the Earth's atmosphere - hence the red color.
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#1176 by FutureSpaceTourist on 20 May, 2017 15:41
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Obviously this may be false ...Quote
There's a rumour in industry that RSC Energia have a pool of paying customers for Moon flyover, and two of them switched to SpaceX recently.
https://twitter.com/tosikceres/status/865715509496606720
The tweet is earlier today and so sounds like a current rumour, which obviously would mean a subsequent flight to the one Elon announced. -
#1177 by Space Ghost 1962 on 20 May, 2017 16:10
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Could be false. However ... from my market research (interviews with potential candidates), they were aware of the RSC Energia offer/means, and wanted more options. So it would be consistent with what was heard from them.
Also, one of the reasons this is so "vague" a market is because both demand and ability to serve being small.
When the number of providers increases (doubling with SX), you'd expect first "switchers", then a few new ones.
I'd put the number of potential committed "customers" at around a dozen worldwide. After Dragon-2 flies with crew, expect about half of these to become signed.
Two things will increase confidence that this will happen:
1) FH flies two time w/o incident
2) Dragon 2 demonstrates on-orbit operation with ECLSS/consumables for the length of the free return flight.
(If I were SX, I'd take the crewed demo flight, and have it well stocked with consumables/props, and after ISS arrival, undock, and move a safe distance (KOS?) away and "formation fly" for free return duration, then redock and complete demo mission.)
It might be possible to "move" the ISS slightly to "grab" a Dragon if the worst case failure were to occur, as an ultimate backup to such a test (depending on stabilization of the disabled Dragon worst case).
Such a Demo mission would prove to ASAP the same mission capability that it wants from Orion before EM-2. That would demonstrate to NASA Dragon-2's capabilities beyond simple ISS missions, perhaps even as a potential LON vehicle for any SLS/Orion missions, which is not a bad thing to have.
As well as encouraging customers for free return. BTW, same would be true for a Soyuz for the RSC Energia too. -
#1178 by Negan on 20 May, 2017 16:40
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2) Dragon 2 demonstrates on-orbit operation with ECLSS/consumables for the length of the free return flight.
I could see a failure of such a demonstration pose some serious questions with regard to NASA's certification process.
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#1179 by Space Ghost 1962 on 20 May, 2017 17:06
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You misunderstand the point of such testing.2) Dragon 2 demonstrates on-orbit operation with ECLSS/consumables for the length of the free return flight.
I could see a failure of such a demonstration pose some serious questions with regard to NASA's certification process.
Testing always delivers confidence. Especially if it fails, because you bring on such a failure in the context of well-planned and on the scene contingencies. You won't have these during actual missions.
Always think "belt and suspenders". As to certification process, it either finds holes for Starliner/Orion, or it confirms the process with actual flight data. There's nothing bad. And its cheaper than EFT-2.
Now, for NASA only - such a capability for long duration flight is a substantial proof for a potential LON capability, extremely cheaply obtained. What else would you need:
1) additional delta-v to allow Dragon-2 to enter/leave LLO (or other). (Or only fly Orion to near lunar halo/EML orbits both can already reach.) Possibly extended tanks in trunk, or propulsion pallet in trunk.
2) demonstrated unmanned mission (Dragon 1) to validate heat shield. Something akin to ETF-1, might even be possible with just a F9 on a highly elliptical orbit.
LON mission concept: Before flight, prep a FH/Dragon-2 for flight with propulsion pallet in HIF. On emergency, prepare/validate for flight, erect, launch.
If no emergency, remove propulsion pallet from free return commercial flight that would fly in a week.
Now, its likely that Orion flights would never need this. However, the public is very unforgiving of "Marooned" astro's, out there suffocating. And at the moment, Dragon-2 would be the "best bet". Cheap contingency.
Don't you think?
