Author Topic: SpaceX Dragon XL  (Read 219277 times)

Online OneSpeed

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Re: SpaceX Dragon XL
« Reply #240 on: 03/30/2020 10:03 am »
What I hear from my sources is that Dragon XL is going to be launched towards Gateway's NRHO the same way as the logistics module and lander elements: Ballistic Lunar Transfer. Which basically means: no TLI required. Transfer time before capture in the NRHO is 12 to 20 weeks.

So S2 delivers Dragon XL to GTO or thereabouts, and Dragon XL burns its Dracos at perigee each orbit until apogee is near lunar orbit?

Offline soyuzu

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Re: SpaceX Dragon XL
« Reply #241 on: 03/30/2020 10:21 am »
What I hear from my sources is that Dragon XL is going to be launched towards Gateway's NRHO the same way as the logistics module and lander elements: Ballistic Lunar Transfer. Which basically means: no TLI required. Transfer time before capture in the NRHO is 12 to 20 weeks.

So S2 delivers Dragon XL to GTO or thereabouts, and Dragon XL burns its Dracos at perigee each orbit until apogee is near lunar orbit?
Not necessarily, Ballistic transfer is more about apogee behavior than perigee behavior. GRAIL, using ballistic transfer to moon, is directly launched to Earth-Sun L1 transfer orbit. On the other hand, Changíe 1, using the method you mentioned to raise apogee and establish TLI, is not ballistic transfer.

https://en.wikipedia.org/wiki/Low-energy_transfer?wprov=sfti1

Offline woods170

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Re: SpaceX Dragon XL
« Reply #242 on: 03/30/2020 11:17 am »
What I hear from my sources is that Dragon XL is going to be launched towards Gateway's NRHO the same way as the logistics module and lander elements: Ballistic Lunar Transfer. Which basically means: no TLI required. Transfer time before capture in the NRHO is 12 to 20 weeks.

So S2 delivers Dragon XL to GTO or thereabouts, and Dragon XL burns its Dracos at perigee each orbit until apogee is near lunar orbit?

S2 does the work to get Dragon XL into the ballistic transfer orbit. Dracos burn only for slight corrections, not for apogee raising.

Offline Zed_Noir

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Re: SpaceX Dragon XL
« Reply #243 on: 03/30/2020 11:36 am »
A couple points:

Docking and Berthing are operations, docking is done under spacecraft control, berthing done with an arm under astronaut control

There are also Docking and Berthing mechanisms, ie IDSS vs CBM.

Confusing point that a Docking system could be berthed (I don't think anyone quite knows how to do this yet), but a Berthing system cannot be docked.

Also, adding a CBM to Dragon XL would be a massive redesign.  Possible you could make an adapter, but it would probably be a very expensive adapter.

Just for unlikely ISS contingencies. Like flying up new ISPR racks.

Instead of external cargo platform on top add CBM port in raised cylindrical section of about half a meter. Deleting the bottom docking port and have quad RCS thruster clusters.

And it would be a Dragon XL variant that only berthed without external cargo.

Offline TheRadicalModerate

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Re: SpaceX Dragon XL
« Reply #244 on: 03/30/2020 11:49 am »
What I hear from my sources is that Dragon XL is going to be launched towards Gateway's NRHO the same way as the logistics module and lander elements: Ballistic Lunar Transfer. Which basically means: no TLI required. Transfer time before capture in the NRHO is 12 to 20 weeks.

BLT still requires a TLI, but it's different than for the direct transfer. 

The direct transfer TLI requires a C3 of about -2.0 km≤/s≤, which will be about 3150 m/s.  This is going to be handled by the FH S2.  After that, you have a lunar flyby maneuver that costs about 180 m/s, and NRHO insertion which costs 250 m/s.  These would be handled by the DXL, requiring a total of 430 m/s.  Total delta-v from LEO to NRHO: 3580 m/s.

The BLT TLI depends on whether you want a 3-4.5 month transfer (about 3200 m/s) or a 4-6.5 month transfer (about 3150 m/s).  After that, the cost for the DXL to insert itself into NRHO is only about 30 m/s.  Total delta-v from LEO to NRHO: 3180-3500 m/s.

So there's a fair amount of difference in your DXL prop requirements, but the TLI that the S2 has to provide is the same or even a little greater than the direct transfer.

Either way, the DXL is going to be very low delta-v vehicle, which depends on the FH S2 for whatever TLI is needed.

Offline pochimax

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Re: SpaceX Dragon XL
« Reply #245 on: 03/30/2020 12:52 pm »
If DragonXL does a slow transfer to NRHO (months), how did SpaceX comply with the unique capability of a fast transfer to Gateway (<30 days)? If NASA request this unique capability.

The standard DragonXL launch and travel is not a fully expendable Falcon Heavy? And the fast transit is a fully expendable?

I' m a little bit lost.
« Last Edit: 03/30/2020 12:53 pm by pochimax »

Offline woods170

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Re: SpaceX Dragon XL
« Reply #246 on: 03/30/2020 02:06 pm »
If DragonXL does a slow transfer to NRHO (months), how did SpaceX comply with the unique capability of a fast transfer to Gateway (<30 days)? If NASA request this unique capability.

The standard DragonXL launch and travel is not a fully expendable Falcon Heavy? And the fast transit is a fully expendable?

I' m a little bit lost.

Can you point to the specific requirement for a <30 days transfer to Gateway? I can't seem to find it.

Offline philw1776

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Re: SpaceX Dragon XL
« Reply #247 on: 03/30/2020 02:52 pm »
I'm guessing these have to be fully expendable Falcon Heavy launches, to get 5 tonnes of cargo to lunar orbit in a spacecraft that has to weigh 5-times-something tonnes - maybe 20 tonnes at TLI with about 1/4th of that mass needed for lunar orbit insertion.

 - Ed Kyle

Can't give you the exact numbers but my source says your mass estimate for the vehicle is way off. As in: your mass estimate for the vehicle is way too high.
Is your source counting the mass needed for lunar orbit insertion?  Maybe there is an entirely separate stage, or maybe the Falcon upper stage does some of the work.  Consider this example.  Apollo 17 entered trans-lunar injection at 46.8 tonnes.  After its lunar insertion burn, the CSM/LM combination weighed 34.72 tonnes, using 26% of the TLI mass for that maneuver. 

So, if payload is 5 metric tons (tonnes)(SpaceX number), then the spacecraft plus payload in lunar orbit has to weigh maybe 2.1 to 2.75 times as much (see Cygnus, ATV, HTV, etc), which gets us to 10.5 to 13.75 tonnes.  That mass divided by 0.74 for the lunar insertion gives 14.2 to 18.6 tonnes at trans-lunar injection. 

Of course this assumes a low lunar orbit delta-v maneuver, which I guess isn't happening in this case.  From TLI to the Gateway NRHO using a lunar flyby would be something like 420 m/s delta-v
, which for a 300 sec ISP Draco assumption would I think require about 13.5% of total TLI mass for the burns, resulting in a 12 to 15.9 tonne TLI mass range.

This seems to me to be in the range requiring an expendable Falcon Heavy based on published and proven capabilities.  SpaceX may be able to do downrange side booster recovery and achieve this result (while expending the center core), or some of it, but downrange recovery of two cores simultaneously on a Heavy flight has yet to be demonstrated.

 - Ed Kyle

This source gives #s for TLI insertion into NRO & departure from NRO for Earth return, 178+250m/s and 190+ 222m/s.

See Figure 2

https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20150019648.pdf

(edited to correct my errors)
« Last Edit: 03/30/2020 03:00 pm by philw1776 »
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Offline mainmind

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Re: SpaceX Dragon XL
« Reply #248 on: 03/30/2020 05:00 pm »
New article on Arstechnica with an interview on Lunar Gateway and Dragon XL, between Eric Berger and NASA's Dan Hartman & Mark Wiese:

https://arstechnica.com/science/2020/03/nasa-officials-outline-plans-for-building-a-lunar-gateway-in-the-mid-2020s/
« Last Edit: 03/30/2020 05:00 pm by mainmind »

Offline rcoppola

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Re: SpaceX Dragon XL
« Reply #249 on: 03/30/2020 05:49 pm »
Wonder if this will need the extended faring?
Read the thread. No fairing, just a "cap" like D1 has.

This from Eric's latest: (Ars article listed up thread)

"Dragon XL will be inside the fairing, so they're taking advantage of that volume that they haven't had..."

Interesting and makes total sense so not to have to worry about aero loads, etc..
« Last Edit: 03/30/2020 05:49 pm by rcoppola »
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Online FutureSpaceTourist

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Re: SpaceX Dragon XL
« Reply #250 on: 03/30/2020 06:53 pm »
No surprise that Elon sees Dragon XL as an interim thing

twitter.com/c3lt_games/status/1244694584493473794?s=21

Quote
Tweet Contents:  @elonmusk Is Starship development still on track?

Why was a new Dragon variant proposed for Lunar Gateway resupply missions?

https://twitter.com/elonmusk/status/1244694967303405575

Quote
Hopefully, Starship will have enough flight history to substitute for Dragon for NASA missions too

Offline Karloss12

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Re: SpaceX Dragon XL
« Reply #251 on: 03/30/2020 07:36 pm »
Even though the hardware is largely derived from legacy equipment, the Earth-Lunar transfer and docking technology will be an important boost for SpaceX experience.
And SpaceX will be making an absolute packet in profit margins for each mission as they know that they are only competing with the astronomically priced Delta IV Heavy.
This is going to be a much celebrated mission for SpaceX.  They will pocket a lot of cash and also develop themselves a new technology.

My bolding
Can you site evidence of anyone making a killing on a NASA contract?
Even Boeing isn't "cleaning up" on SLS.  They are just getting fixed or award fees for the last decade, and that's good enough.
The company I work for has done a many instruments and missions for NASA.  It's a good business.  Higher margin than the commodity stuff.  But it doesn't bloat the bottom line.
A big issue for SpaceX is that this is seems to be a fixed price contract, IDIQ, for a system involved with astronauts, and at any time NASA can increase the requirements.  SpaceX has experience with this, and probably didn't underbid the competition by $1.6B again. 
But it remains a risk, not a bonanza.
I site the laws of capitalism.  In particular, competition.
The FH costs about $120mil.  The Delta IV is $400mil.
SpaceX will have bid around $350mil and be making a packet.  Good on them.  They need the cash to fund R&D.
One of the great things about NSF is people posting can have good to great knowledge of the engineering or industry.
Just because it doesnít agree with your intuition is no reason to ignore a post with better background. Mine is not authoritative, but if none of the real experts reading this thread dispute my post, which has happened for others, restating your guess isnít helping anyone else.
I share your hope that Dragon XL generates some of the profits SpaceX needs to fund their amazing ambitions, but it wonít be a big fraction. It doesnít work that way.
Edit: Your concept  of how Aerospace contracts are overpriced is interesting but not at all accurate. While some aerospace companies are rapacious, itís much more sophisticated than pulling prices out of the air. We are all aggrieved by it, but snarling inaccuracies doesnít help anyone fix anything.
I am one of those technical and commercial experts who works with multi-million pound projects in various industries including Aerospace.  So this is a case of me (an expert) disagreeing with other so called experts.
I generate an accurate estimate for the design, fabrication and management of equipment at a customers site and a standard profit margin is applied to my estimate to get a standard bid price.  If we know that my company is the only bidder then the project manager will take my standard quote price and multiply it by 2-3.  There are other multipliers for whether you want the job.  The size of these multipliers is very arbitrary and does often depend a on your mood at the time, and sometimes the direction of the wind.
When the customer comes back querying the surprisingly high price as they often to, a couple of replies include:
-There are extra costs for the tight schedule.
-We are already at 100% capacity with other projects and are doing you a favour to fit this project in.
-This is our price.

Non of these replies can be desputed or analysed by the customer.  They just have to take it or leave it.

When our customer stipulates that we must use a specific supplier, the quote from that supplier always doubles from what we paid for recent similar equipment.  When we interrogate the price, they come up with the excuses above.  This is how it works when there is no competition.

When you throw politicians into the mix like with Aerospace, the price just gets even worse.

I think people on this forum over exaggerate the governments ability to intergate a suppliers price.

The most recent article says that Dragon XL is a Variant of Dragon 2.
Going from the Dragon 1 variant to the Dragon 2 Variant cost over $2bill.
I think with a lack of competition and a tight schedule squeeze, a similar price could be justified for the Dragon XL varient.
Remember that project cost and project price are two totally different things and justifying a large difference between the two is a surprisingly easy thing to do when the commercial conditions are right.

Offline pochimax

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Re: SpaceX Dragon XL
« Reply #252 on: 03/30/2020 08:56 pm »
If DragonXL does a slow transfer to NRHO (months), how did SpaceX comply with the unique capability of a fast transfer to Gateway (<30 days)? If NASA request this unique capability.

The standard DragonXL launch and travel is not a fully expendable Falcon Heavy? And the fast transit is a fully expendable?

I' m a little bit lost.

Can you point to the specific requirement for a <30 days transfer to Gateway? I can't seem to find it.

File: Attachment_01_GLS_SOW.pdf
5.0 MISSION UNIQUE CAPABILITIES (SUBCLIN 103) [pages 29-30]

Fast Transit to Gateway: Provide end-to-end cargo delivery services withcargo transit time of 30 days or less. NASA shall have the ability to order this capability within the time defined in the GLS Space System Architecture contract attachment.


Online Robotbeat

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Re: SpaceX Dragon XL
« Reply #253 on: 03/30/2020 09:27 pm »
Does anyone have a good estimate for Falcon Heavy near-escape capability for core-expendable and booster down-range recovery mode?  Such a mode does not yet exist, of course, because SpaceX hasn't demonstrated dual downrange recovery.  I know about Elon's 10% payload reduction estimate, but he never said if that was for LEO or GTO, etc.  My guess is 10% for LEO, but a bigger reduction for higher energy orbits. 

My estimate for 5 tonnes cargo to Near Rectilinear Halo (lunar) Orbit (NRHO) is that 12 to 16 tonnes (payload, spacecraft, propellant) would need to separate into TLI, providing 10.5 to 13.8 tonnes to NRHO (13.5% of mass used for the burns to NRHO).  The three-core recovery mode for Falcon Heavy only provides 8 tonnes to GTO, while fully expendable Falcon Heavy is listed at 26.7 tonnes GTO or 16.8 tonnes trans-Mars.

 - Ed Kyle
Citation needed for just 8 tons GTO with 3 booster recovery. I think the assumptions for that are much more conservative (sandbagged) than those for the 16.8tonnes TMI estimate.

Also, center core expended and 2 cores RTLS is a thing.

I think that comes directly from SpaceX:

https://www.spacex.com/about/capabilities
Nope!

Read again! That’s just the performance you get for $90m; it says nothing about what the mode of launch would be at that price.

Secondaries? RTLS for all 3 cores? Extra margin for a softer recovery? Cheaper/lighter payload adapter? Who knows! It isn’t specified!

We do know from that page it can do 26.7t GTO in fully expendable mode.

Maybe an official slide from Spacex presented at Hans Koenigsman's Ted talk at IAC 2018 (you can find the video on youtube too) will be sufficient.
Notice the plus sign on the Expendable Falcon Heavy figure.
All these figures could be outdated, but they are the figures SpaceX gave out officially. I think the figures on their website are estimates with close to no fuel margins, which might be ok for an internal mission or for rocket comparison purposes but not for commercial launches or government launches. The NASA LSP figures could also be very conservative, there is no doubt in that.
Much better.

And yes, I think you're right about fuel margins and conservatism.

What this means is that over time, the usable performance will improve (>90% probability) significantly as uncertainty about performance and margins is reduced due to operational experience. Plus performance tweaks.

As far as the 15,000+kg for full expendable... they'd probably need a much beefier payload adapter. Few people need that capability.
« Last Edit: 03/30/2020 09:30 pm by Robotbeat »
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Offline baldusi

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Re: SpaceX Dragon XL
« Reply #254 on: 03/30/2020 09:49 pm »
[...]
If the Gateway comes to fruition, this is a relatively low-cost design evolution for cargo supply. This isn't something that SpaceX would have wanted on their roadmap, and I doubt they anticipate any commercial market for a vehicle like this, but it would have been poor form for SpaceX not to bid. SpaceX has a strategic interest in playing nice with NASA, and while developing Dragon XL would be a distraction, it's not an overly burdensome detour. NASA will pay enough to make it worthwhile for SpaceX even if they're the only conceivable customer.

This is indeed a relatively low-cost design evolution.
BUT
This is very much something that SpaceX is very willing to build and fly for NASA. Reason: SpaceX needs every dollar it can get to finance the development of Starship and Superheavy. Not just now, but also 10 years from now because, like FH and F9, Starship and Superheavy will be in near-constant development & improvement for at least a decade to come.
[...]
I want to point out that this contract gets SpaceX someone to foot the development of rad-hard avionics, deep space GNC, telemetry and environment design, and experience on deep space mission in general. Radiation effect on electronics, heat rejection, power generation, navigation and comms are all different for deep space than what SpaceX has been doing up to now. These are not trivial costs and, specially for their highly iterative ways, can really benefit from this contract.
Whatever changes they need to perform to a Dragon Cargo 2 to make XL, are things that will basically be copied almost verbatim to Starship. So I think they were more than eager to get this contract down.

Offline Coastal Ron

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Re: SpaceX Dragon XL
« Reply #255 on: 03/30/2020 10:00 pm »
I am one of those technical and commercial experts who works with multi-million pound projects in various industries including Aerospace.  So this is a case of me (an expert) disagreeing with other so called experts.
I generate an accurate estimate for the design, fabrication and management of equipment at a customers site and a standard profit margin is applied to my estimate to get a standard bid price.  If we know that my company is the only bidder then the project manager will take my standard quote price and multiply it by 2-3.  There are other multipliers for whether you want the job.

Yes, in the commercial marketplace you can sell anything for any price. No one is disputing pricing in the commercial marketplace.

Quote
When you throw politicians into the mix like with Aerospace, the price just gets even worse.

Actually in the vast amount of government contracting politicians are not involved, and politicians can only really be involved through legislation, like with the SLS and Orion programs.

Quote
I think people on this forum over exaggerate the governments ability to intergate a suppliers price.

Many of us have first hand experience with government contracting, and what can and can't be done. Every American should feel good about the fact that government procurement professionals really are good at what they do, and it takes incompetence in agency leadership, or specific legislation by politicians (i.e. pork) to allow gross profiteering.

Quote
The most recent article says that Dragon XL is a Variant of Dragon 2.
Going from the Dragon 1 variant to the Dragon 2 Variant cost over $2bill.

SpaceX received a $2.6B contract for Commercial Crew, and as of October of 2019 Elon Musk felt they would not exceed that contract value.

Quote
I think with a lack of competition and a tight schedule squeeze, a similar price could be justified for the Dragon XL varient.

Lack of competition? SpaceX responded to a public RFP that NASA issued last year for a 15-year, $7B commercial supply services IDIQ contract. They had competition. And all the finalists would have had a cost review so that NASA could ensure that the eventual winner wasn't low-balling the bid - which does happen, and which is why the government does contract audits.

No doubt SpaceX had an advantage due to their extensive spacecraft experience, and due to the fact that they can launch their own vehicles - that cuts out one layer of extra profit.
If we don't continuously lower the cost to access space, how are we ever going to afford to expand humanity out into space?

Online Robotbeat

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Re: SpaceX Dragon XL
« Reply #256 on: 03/30/2020 10:22 pm »
[...]
If the Gateway comes to fruition, this is a relatively low-cost design evolution for cargo supply. This isn't something that SpaceX would have wanted on their roadmap, and I doubt they anticipate any commercial market for a vehicle like this, but it would have been poor form for SpaceX not to bid. SpaceX has a strategic interest in playing nice with NASA, and while developing Dragon XL would be a distraction, it's not an overly burdensome detour. NASA will pay enough to make it worthwhile for SpaceX even if they're the only conceivable customer.

This is indeed a relatively low-cost design evolution.
BUT
This is very much something that SpaceX is very willing to build and fly for NASA. Reason: SpaceX needs every dollar it can get to finance the development of Starship and Superheavy. Not just now, but also 10 years from now because, like FH and F9, Starship and Superheavy will be in near-constant development & improvement for at least a decade to come.
[...]
I want to point out that this contract gets SpaceX someone to foot the development of rad-hard avionics, deep space GNC, telemetry and environment design, and experience on deep space mission in general. Radiation effect on electronics, heat rejection, power generation, navigation and comms are all different for deep space than what SpaceX has been doing up to now. ...
Different in amount, not in kind. LEO is same as deep space, just different dosing rates. Same order of magnitude rates.
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Offline TheRadicalModerate

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Re: SpaceX Dragon XL
« Reply #257 on: 03/30/2020 10:23 pm »
If DragonXL does a slow transfer to NRHO (months), how did SpaceX comply with the unique capability of a fast transfer to Gateway (<30 days)? If NASA request this unique capability.

The standard DragonXL launch and travel is not a fully expendable Falcon Heavy? And the fast transit is a fully expendable?

I' m a little bit lost.

This is pretty straightforward:  The FH S2 puts the DXL into TLI, which is a few hundred m/s more or less delta-v than about 3180 m/s, depending on whether the mission is a fast transfer or a ballistic lunar transfer.  After that, the DXL separates from the S2 and has to generate its own delta-v to complete NRHO insertion for a fast transfer (430 m/s), or the BLT insertion (about 30 m/s).

So the requirement for the DXL is that it be able to generate at least 430 m/s of delta-v when fully loaded, plus another couple of hundred m/s for disposal.  (No clue on what they'll do there; I'm betting on a graveyard orbit of some kind.)  Call it 700 m/s of delta-v total.

Figure a 3.5 t dry mass with 8 t of payload (I think SpaceX will design to this, even though the contract only calls for 5 t), and the Draco Isp of 300 s requires 3.1 t of MMH/NTO prop.  So your total launch mass is 14.6 t, which, not coincidentally, is pretty close to what an FHE can throw to a vanilla-flavored TLI.

The amount of MMH/NTO can be reduced for BLTs, but BLTs come in two flavors:  Slow (where TLI takes you way beyond the Moon's orbit and let the Sun raise the perigee and increase the inclination, which takes 2-4 months), and really slow (where TLI is lower energy, and the Moon is used for a gravity assist, which takes 4-6 months).  The slow TLI's take an extra 100 m/s or so over the fast transfer TLI's.  The really slow ones takes about the same TLI delta-v as the fast transfer.

So max payloads will differ a bit.  The launch mass may have to be reduced for slow TLI's, so the S2 has enough prop, but most of that reduction can be DXL prop.  Fast transfers need more DXL prop, so probably can handle less payload.  And really slow BLTs give you the optimal payload but they're... really slow.

My guess is that heavily loaded DXLs will require an FHE, but DXLs with 5 t of payload in a BLT will likely be launchable on an FH2R.

Make sense?
« Last Edit: 03/30/2020 10:39 pm by TheRadicalModerate »

Offline TheRadicalModerate

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Re: SpaceX Dragon XL
« Reply #258 on: 03/30/2020 10:37 pm »
Different in amount, not in kind. LEO is same as deep space, just different dosing rates. Same order of magnitude rates.
It's different in kind, too.  You don't get much galactic cosmic radiation inside the Van Allen Belts.  GCRs are highly energetic heavy ions.  That's certainly a different kind of hardening for electronics--and people.

Offline baldusi

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Re: SpaceX Dragon XL
« Reply #259 on: 03/30/2020 11:16 pm »
[...]
If the Gateway comes to fruition, this is a relatively low-cost design evolution for cargo supply. This isn't something that SpaceX would have wanted on their roadmap, and I doubt they anticipate any commercial market for a vehicle like this, but it would have been poor form for SpaceX not to bid. SpaceX has a strategic interest in playing nice with NASA, and while developing Dragon XL would be a distraction, it's not an overly burdensome detour. NASA will pay enough to make it worthwhile for SpaceX even if they're the only conceivable customer.

This is indeed a relatively low-cost design evolution.
BUT
This is very much something that SpaceX is very willing to build and fly for NASA. Reason: SpaceX needs every dollar it can get to finance the development of Starship and Superheavy. Not just now, but also 10 years from now because, like FH and F9, Starship and Superheavy will be in near-constant development & improvement for at least a decade to come.
[...]
I want to point out that this contract gets SpaceX someone to foot the development of rad-hard avionics, deep space GNC, telemetry and environment design, and experience on deep space mission in general. Radiation effect on electronics, heat rejection, power generation, navigation and comms are all different for deep space than what SpaceX has been doing up to now. ...
Different in amount, not in kind. LEO is same as deep space, just different dosing rates. Same order of magnitude rates.
I assume you are referring only to the radiation hardening of the electronics and concurring with the rest of the differences. Assuming so, AIUI, there are certain differences, specifically wrt heavy nucleus ions. And LEO is not the same. Up to 500km is one thing because you are mostly below the Van Allen belts. But higher you get into the "hot" volumes. So the ISS environment is, not surprisingly, the most benign case.
On the other hand, these moon missions are special because there are the very specific mission beyond the Van Allen belt that do not require 10yr+ of working electronics.

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