Commercial HLV and R&D

[Nathan]

If the studies show it workable, send the lander to LLO early using a VASIMR solar powered tug.  It's obviously in the game given the NASA JSC solicitation last week.

http://forum.nasaspaceflight.com/index.php?topic=20244.0

>
In addition, Studies will be conducted to evaluate a Lunar Tug concept utilizing Variable Specific Impulse Magneto-plasma Rocket (VASIMR) engine capabilities from Low Earth Orbit to Lunar Orbit and libration points.

NASA/JSC intends to purchase these services from Ad Astra Rocket Company.
>

I worry about the time spent in the Van Allen belts with these low thrust trajectories. The 39 day transit to Mars requires 8 days in the spiral. A 250 tonne version spends only 4 days in spiral and still manages 53 day transit - excellent. But what about exposure? What is a safe transit time on a spiral trajectory?

[docmordrid]

The lander/tug wouldn't be manned until it was in lunar orbit...the crew coming later on another rig that wouldn't loiter. 

Mars missions would be different. First a bit about the radiation doses for the Van Allen belts;

The unit we'll be using is the Sievert, or Sv. 1 Sv = 1 joule/kg of equivalent dose and is used to approximate biological effect vs. just pure flux. The natural background dose at the Earths surface averages about .0025 Sv/year. 3 Sv of instantaneous exposure would have an approximately 50% mortality (LD50). 

Most all of the strong radiation exposure would come from the inner Van Allen belt in the form of high energy electrons and protons.  The exposure rate I found is about 25-30 Sv/year, which would amount to 0.07+ Sv/transit-day.  Balance wise, the inner belt is mostly protons while the outer belt is mostly electrons at lower energies. The electrons could be stopped by a few millimeters of aluminum, but not the protons which are 1,836 times as massive.  That would take lead, and that's not an option because of its high weight.

Best strategy would be to start the spiral outside the inner belt, avoiding the highest proton flux. 

Extra points if a crewed vessel had a Bigelow hab for living space as they have made a big deal of designing in water blankets for shielding.  That plus the 16" thick walls would be a nifty radiation shield. 

[Antares]

I think the premise of this topic is screwy, no offense to the OP.

I think I'm one of the biggest proponents of existing, commercially available LVs because there are multiple, other, private-sector customers for them.

Who, right now, needs a BFR besides government users or projects?  There's no private demand for this.  IMO a Bigelow-esque business case wouldn't close even sharing development costs with government users.

There's no point in talking about technical solutions or government applications if the economic solution doesn't close.

[Lee Jay]

I think the premise of this topic is screwy, no offense to the OP.

It's not the OP's premise.  It's in the 2011 budget request to do R&D for HLVs, possibly involving commercial entities.

[docmordrid]

Research facilities, public or private, often defy economics. Been there, done that.

[Ben the Space Brit]

I think the premise of this topic is screwy, no offense to the OP.

I think I'm one of the biggest proponents of existing, commercially available LVs because there are multiple, other, private-sector customers for them.

Who, right now, needs a BFR besides government users or projects?  There's no private demand for this.  IMO a Bigelow-esque business case wouldn't close even sharing development costs with government users.

FWIW - I suspect that these wouldn't be commercial solutions in the strictest sense of the word.  They would be more like DoD procurement projects with only the minimum necessary NASA oversight and involvment.  The idea is to remove the cost overruns from the MSFC dream factory by forcing a more 'hands-off' approach.

[Antares]

I totally agree, but that doesn't require commercial.  It requires better requirements management within the government.  DoD probably has proportionately as much problem with requirements creep as well, cf NPOESS, FIA, etc.

[yg1968]

I think the premise of this topic is screwy, no offense to the OP.

I think I'm one of the biggest proponents of existing, commercially available LVs because there are multiple, other, private-sector customers for them.

Who, right now, needs a BFR besides government users or projects?  There's no private demand for this.  IMO a Bigelow-esque business case wouldn't close even sharing development costs with government users.

There's no point in talking about technical solutions or government applications if the economic solution doesn't close.

I wasn't trying to propose or defend any option, I was trying to better understand the HLV R&D option. I added the word commercial because NASAwatch seemed to believe that the HLV would be "commercial". But I am not clear what is meant by "commercial" in this context. Although Bolden said that an HLV could perhaps be built by ULA. Perhaps that is what he meant by commercial. I am still trying to understand that part of the budget.

[Patchouli]

I think the premise of this topic is screwy, no offense to the OP.

I think I'm one of the biggest proponents of existing, commercially available LVs because there are multiple, other, private-sector customers for them.

Who, right now, needs a BFR besides government users or projects?  There's no private demand for this.  IMO a Bigelow-esque business case wouldn't close even sharing development costs with government users.

There's no point in talking about technical solutions or government applications if the economic solution doesn't close.

I wasn't trying to propose or defend any option, I was trying to better understand the HLV R&D option. I added the word commercial because NASAwatch seemed to believe that the HLV would be "commercial". But I am not clear what is meant by "commercial" in this context. Although Bolden said that an HLV could perhaps be built by ULA. Perhaps that is what he meant by commercial. I am still trying to understand that part of the budget.

Boeing and ATK could sell a SDLV through USA which would make the definition of commercial.

It would be interesting to see if a non NASA entity would take interest in a Shuttle-C or Jupiter type vehicle if one was on the market.

It also should be noted a F9-H with a cryogenic upper stage sized for a three core vehicle operating in two stage mode vs 2.5 stage mode may meet the definition of an HLV.

Though if they get Merlin 2 a Saturn V INT-21 class LV would not be out of the question.

[Dave G]

I think I'm one of the biggest proponents of existing, commercially available LVs because there are multiple, other, private-sector customers for them.

Who, right now, needs a BFR besides government users or projects?  There's no private demand for this.  IMO a Bigelow-esque business case wouldn't close even sharing development costs with government users.

There's no point in talking about technical solutions or government applications if the economic solution doesn't close.

This is a really good point, and I have to agree.

The idea is for the commercial launchers to have some "skin in the game".  In economic terms, that means they must have multiple potential customers.  There's probably only 1 customer that needs a really heavy lift vehicle, so the commercial option doesn't seem to make sense for that.

Don't get me wrong, I'm a huge supporter of the commercial option.  But it has to make sense economically.  Satellites use the same size rockets required for crew to LEO, so that makes sense.

For a permanent Moon-base, or a Mars mission, you'll need a really big launcher to get large payloads to LEO, or medium sized payloads beyond LEO.  But you don't need people to launch with that big stuff.

So ironically, a government funded cost-plus unmanned heavy lift vehicle is probably more important for human space exploration.  We can use commercial crew launchers to rendezvous with the HLV payload.

Specifically, Ares V is probably more important for human exploration than Ares I / Orion.

[mmeijeri]

For a permanent Moon-base, or a Mars mission, you'll need a really big launcher to get large payloads to LEO, or medium sized payloads beyond LEO.

Actually, you don't. There are obviously ways to do it with a huge launcher, but there are excellent and much more flexible ways to do it with EELVs. Exploration doesn't need HLV. Commercial development of space would be greatly helped by its absence. That should be enough to decide against HLV.

[Dave G]

For a permanent Moon-base, or a Mars mission, you'll need a really big launcher to get large payloads to LEO, or medium sized payloads beyond LEO.

Actually, you don't. There are obviously ways to do it with a huge launcher, but there are excellent and much more flexible ways to do it with EELVs. Exploration doesn't need HLV. Commercial development of space would be greatly helped by its absence. That should be enough to decide against HLV.

It just seems like an HLV would deal with so many issues better than a bunch of EELVs.  For example, how would you launch a Mars descent heat shield on a bunch of EELVs?

[Robotbeat]

For a permanent Moon-base, or a Mars mission, you'll need a really big launcher to get large payloads to LEO, or medium sized payloads beyond LEO.

Actually, you don't. There are obviously ways to do it with a huge launcher, but there are excellent and much more flexible ways to do it with EELVs. Exploration doesn't need HLV. Commercial development of space would be greatly helped by its absence. That should be enough to decide against HLV.

It just seems like an HLV would deal with so many issues better than a bunch of EELVs.  For example, how would you launch a Mars descent heat shield on a bunch of EELVs?

By saving tens of billions on not having to pay for an HLV and its infrastructure:
Five ways:
1) Horizontal heatshield (i.e. Mars entry on your side, not your bottom)
2) develop a segmented heatshield
3) develop an inflatable heatshield
4) use a fully propulsive descent stage (not a good option, but feasible with nuclear thermal rockets or propellant depots, especially with high-Isp tugs)
5) develop ISRU and perform a propulsive descent using the ascent engines

[mmeijeri]

4) use a fully propulsive descent stage (not a good option, but feasible with nuclear thermal rockets or propellant depots, especially with high-Isp tugs)

Or Phobos/Deimos ISRU or a reusable NTR cargo lander exporting hydrocarbon and oxygen to LMO. Zubrin proposed the NTR lander (not the export), using CO2 as working mass. Isp wasn't great even with nukes, but sourcing the CO2 locally is trivial and the required delta-v isn't all that high. You would have to be careful not to drop the lander on your base as that would be considered bad form.

I think fully propulsive isn't a bad option at all, especially since you need a major propulsive component anyway if you want to land large payloads, such as crewed landers and surface infrastructure. That doesn't mean you wouldn't want to take advantage of aerodynamic deceleration to the degree it doesn't need large fairings. Cheaper is always good. Giving researchers in politically important government design centers something valuable to do is good too.

[mmeijeri]

This is probably the paper I was talking about:

NUCLEAR THERMAL ROCKETS USING INDIGENOUS EXTRATERRESTRIAL PROPELLANTS

[Dave G]

By saving tens of billions on not having to pay for an HLV and its infrastructure:
Five ways:
...

Is there any way to build a BFR for less?

No human rating.  No capsule.  Just a big launcher. 

Once you have the launcher, cost per pound is much less.

Also, we're talking about a BFR using a cost-plus procurement method, but not necessarily the same old military suppliers.

What would be the minimum cost to develop a BFR?

[Downix]

By saving tens of billions on not having to pay for an HLV and its infrastructure:
Five ways:
...

Is there any way to build a BFR for less?

No human rating.  No capsule.  Just a big launcher. 

Once you have the launcher, cost per pound is much less.

Also, we're talking about a BFR using a cost-plus procurement method, but not necessarily the same old military suppliers.

What would be the minimum cost to develop a BFR?

Look at the records on Sea Dragon to get an idea

[Dave G]

Look at the records on Sea Dragon to get an idea

http://en.wikipedia.org/wiki/Sea_Dragon_(rocket)
Certainly qualifies as a BFR.

And some recent start-ups also advocate a floating ocean launch without a platform.

But would it work?

[kch]

Look at the records on Sea Dragon to get an idea

http://en.wikipedia.org/wiki/Sea_Dragon_(rocket)
Certainly qualifies as a BFR.

And some recent start-ups also advocate a floating ocean launch without a platform.

But would it work?

Non-tagged URLs with closing parens are handled "Incorrect-ly" ... this should work:

Wiki article on Sea Dragon

[Serafeim]

No human rating.  No capsule.  Just a big launcher. 

thats maybe its enough.also russian angara have 50t versions .
Everyone according to Bolden wants a hlv and believe in its neccesity.even a 50t launcher ,simple,not manned just for sience missions for start(Europa,Titan ,Mars sample return,missions etc)and when a proper crewed vehicle is ready for beyond Leo,Dragon, atv derived,russian or whatever.this lancher can act as an eds..