"Space Adventures" has a customer for the lunar Soyuz!

[Stan Black]

If you click on those links, you'll see that Space Adventures is not proposing a reflight of the Zond program.

They use a standard Soyuz to launch the crew and Zenit (in their animation) to launch the EDS, with docking in Earth orbit.

Ouch! What is it with all current cis-Lunar schemes and 'eyes-out' Earth departure burns?

Some versions mention a habitation module with the Blok-DM. I guess the crew could move their Kazbek couches to a forward facing location?

http://www.energia.ru/eng/news/news-2006/im/public_07-01_10.jpg
http://www.energia.ru/eng/news/news-2006/public_07-01.html

http://www.zvezda-npp.ru/engl/kasbek.html

[Ben the Space Brit]

Some versions mention a habitation module with the Blok-DM. I guess the crew could move their Kazbek couches to a forward facing location?

http://www.energia.ru/eng/news/news-2006/im/public_07-01_10.jpg
http://www.energia.ru/eng/news/news-2006/public_07-01.html

http://www.zvezda-npp.ru/engl/kasbek.html

How big and heavy is Pirs? Could you build something with the same OML to act as an in-flight hab? After all, we're only talking about a crew of three here and the pilot/flight engineer would want to spend most of his time in the descent module keeping an eye on the spacecraft's functions.

[Danderman]

How big and heavy is Pirs? Could you build something with the same OML to act as an in-flight hab? After all, we're only talking about a crew of three here and the pilot/flight engineer would want to spend most of his time in the descent module keeping an eye on the spacecraft's functions.

The problem is moving Pirs to the lunar stack, there is no way to do so with using magic. Plus, Pirs is really really heavy for the job, and doesn't provide any of the necessary functions for the mission, apart from providing volume.

[Danderman]

So, what would be the launch configuration for this? A Soyuz on top of a Proton-M? Or can BRIZ-M be fit on top of the R7?

http://www.constellationservices.com/Lunar_ExpressSM_system_brief_NewSpace2006_20_July_2006.pdf

http://www.constellationservices.com/lunarexpresssmsystem.html

Note the dates on this page.

If you can read Russian, check this out:

http://www.kp.ru/daily/23335/31058/

[Serafeim]

This "plan" shows that the moon plans are not dead whatever Obama proposes.nasa ,or tother agencies ,or private companies will go again to the moon,and this time to stay..

[Ben the Space Brit]

The problem is moving Pirs to the lunar stack,

No, that isn't a problem because I'm not proposing that Pirs is moved to  the lunar stack.

What I was wondering was if there could be a hab/storage module based on the same Outer Mould Line (OML) riding on the EDS.  According to Stan Black's post above, there was some consideration of having a hab module on the stack but mass constraints come into play.  I was specifically asking if something the size of Pirs was big enough for the job or if it was too big because of its empty mass.

[fregate]

Mission profile
2 options, for both modified Soyuz-TMA (launched on Soyuz FG LV) would perform EOR with Block DM (luanched on Proton - M LV)

Option A
     - Crew in Soyuz-TMA launched on Soyuz FG LV;
     - EDS Block DM launched on Proton M;
     - EOR on LEO 200 km (within 2 days);
     - TLI maneuver for circumnavigate the Moon.

Option B
      - Crew in Soyuz-TMA docked to ISS;
      - EDS Block DM launched on Proton M;
      - EOR on LEO 200 km (within 2 days) - Soyuz TMA undocks from ISS and  docks with  Block DM;
      - TLI maneuver for circumnavigate the Moon.
 
An additional mission module (half or full-sized Soyuz habitation module) with a passive RDS unit to be integrated with standard Block DM space tug. 

[Danderman]

Mission profile
2 options, for both modified Soyuz-TMA (launched on Soyuz FG LV) would perform EOR with Block DM (luanched on Proton - M LV)

Option A
     - Crew in Soyuz-TMA launched on Soyuz FG LV;
     - EDS Block DM launched on Proton M;
     - EOR on LEO 200 km (within 2 days);
     - TLI maneuver for circumnavigate the Moon.

Option B
      - Crew in Soyuz-TMA docked to ISS;
      - EDS Block DM launched on Proton M;
      - EOR on LEO 200 km (within 2 days) - Soyuz TMA undocks from ISS and  docks with  Block DM;
      - TLI maneuver for circumnavigate the Moon.
 
An additional mission module (half or full-sized Soyuz habitation module) with a passive RDS unit to be integrated with standard Block DM space tug. 

These indeed are the two options. BTW, for Option 2, EOR is within 35 km +- of the ISS orbit, no need or capability of the drop to 200 km.

The economies drive the use of the 2nd option, since effectively the Soyuz is used twice, once for an ISS mission, and the 2nd time for the lunar mission. This demands a mission module, to avoid any mods to Soyuz that detract from its taxi role.

[Danderman]

What I was wondering was if there could be a hab/storage module based on the same Outer Mould Line (OML) riding on the EDS.  According to Stan Black's post above, there was some consideration of having a hab module on the stack but mass constraints come into play.  I was specifically asking if something the size of Pirs was big enough for the job or if it was too big because of its empty mass.

Pirs is far too large for the lunar mission module. Too much dead mass.

[fregate]

These indeed are the two options. BTW, for Option 2, EOR is within 35 km +- of the ISS orbit, no need or capability of the drop to 200 km.

The economies drive the use of the 2nd option, since effectively the Soyuz is used twice, once for an ISS mission, and the 2nd time for the lunar mission. This demands a mission module, to avoid any mods to Soyuz that detract from its taxi role.

Oops - my apologies. Option B orbit - 400 km LEO (severe case of copy and paste)

[Danderman]

These indeed are the two options. BTW, for Option 2, EOR is within 35 km +- of the ISS orbit, no need or capability of the drop to 200 km.

The economies drive the use of the 2nd option, since effectively the Soyuz is used twice, once for an ISS mission, and the 2nd time for the lunar mission. This demands a mission module, to avoid any mods to Soyuz that detract from its taxi role.

Oops - my apologies. Option B orbit - 400 km LEO (severe case of copy and paste)

Technically, either the apogee or perigee of the assembly orbit must be 35 km from ISS, its a hardware limitation of the system.

[fregate]

IMHO Mission module would be integrated with Block-DM and will have a passive RDS unit and there is no SEPARATE Mission module.   

[clb22]

IMHO Mission module would be integrated with Block-DM and will have a passive RDS unit and there is no SEPARATE Mission module.   

There is a delta-v problem and various prohibitive technical problems for this plan.

Multiple variants of Block-DM are currently in use. I pick the one used in Proton:
Block DM-2 11S861
Gross Mass: 17.3mt; Empty Mass: 2.3mt; isp: 352sec; Lox/kerosene

If you max-out Proton you end up with a 4mt mission module + RCS attached to the Block DM, which is quite alright for our purposes (3 crew in Soyuz for an 8 day lunar swingby mission). Now, let's forget for a moment that the Block DM's loiter time on orbit is very limited and a very quick rendezvous between our modified Soyuz (let's call it Soyuz-TMA-X) and this Block DM-2+MM stack is necessary for mission success.
 
Even if we assume 7.2mt for this modified Soyuz-TMA-X (it probably will weight more due to heatshield changes of the capsule), the Block DM will not be able to provide the required delta-v for TLI. Not even close. Even without a new mission module, the Block DM might only just barely provide the required delta-v for TLI for our 7.2mt Soyuz, but without margins necessary for a safe mission architecture.

All that said, using a mission module with the current in-use Block DM on a Proton for a Soyuz lunar flyby is impossible. A new larger version of the Block-DM with better loiter time, RCS etc. would have to be developed. And if you want to take a 2-4mt MM up there with it, Proton doesn't have the capacity to do so, you need a larger rocket (Angara is still too far away to baseline it for this job...).

I see a different variant of a near-term lunar swingby mission much more likely, one that can be accomplished more easily and with enough margin to allow for a safe architecture. A dedicated modified Soyuz for only a crew of two, involving modifications to the Orbital module and the capsule and the use of Briz-M as the EDS (Briz-M: 22.1mt gross, 19.8mt propellant, isp: 326sec, N2O4/UDMH). NO dedicated mission module at all, the reduction in crew size and modifications to the orbital module (toilet etc.) are enough for an extended space flight. While Briz-M has lower isp than Block-DM, it has a maximum loiter time of 24-30 hours which allows for safe on-orbit rendezvous  and is sized appropriately (22mt) to fit on Proton as a payload while still providing enough delta-v for a slightly heavier Soyuz (Soyuz-TMA-X of maybe 7.5mt instead of 7.2mt) for a lunar swingby of a crew of 2. The Briz-M of course needs modifications to its RCS system and a docking mechanism.

[Danderman]

Allocating 4 metric tons to the mission module indeed make the architecture very problematic.

Note that the Soyuz orbital module has a mass of 1.2 tons.

Your analysis of Briz-M does not take into account that when Briz-M is fully loaded, it is not carried into orbit by Proton.

[clb22]

Allocating 4 metric tons to the mission module indeed make the architecture very problematic.

Note that the Soyuz orbital module has a mass of 1.2 tons.

Your analysis of Briz-M does not take into account that when Briz-M is fully loaded, it is not carried into orbit by Proton.

Proton-M payload specs:
23,000kg to circularized 180km orbit 51.5 degree according to ILS Proton Launch System Mission Planner's Guide (revision July 2009);

Maximum payload fairing diameter: 4.2m

Mass of Briz-M 22,170kg, thereoff propellant: 19,800kg; length 2.61m, diameter 4m

As a consequence, Briz-M fits on Proton-M as a payload as is, fully fuelled.


Required delta-v for TLI (with 5-10% margin) ~3.4km/s
Maximum payload to TLI by use of Briz-M as an EDS: ~8,000kg