New Mars Forums

Official discussion forum of The Mars Society and MarsNews.com

You are not logged in.

Announcement

Announcement: As a reader of NewMars forum, we have opportunities for you to assist with technical discussions in several initiatives underway. NewMars needs volunteers with appropriate education, skills, talent, motivation and generosity of spirit as a highly valued member. Write to newmarsmember * gmail.com to tell us about your ability's to help contribute to NewMars and become a registered member.

#1 2007-01-14 06:34:12

Michael Bloxham
Member
From: Auckland, New Zealand
Registered: 2002-03-31
Posts: 426

Re: Really big rockets

Here's something I doodled in mspaint while thinking about applying the Delta-IV growth options to these new 10m diameter tanks and RS-68b engines. Enjoy.

PARISLaunchSystem.jpg


- Mike,  Member of the Clean Slate Society

Offline

#2 2007-01-14 10:58:57

cIclops
Member
Registered: 2005-06-16
Posts: 3,230

Re: Really big rockets

Mere toys smile

Checkout the 54,000 mT Daedalus fusion powered starship - stand well clear when she fires that engine!

350px-Daedaluscap158.JPG


Let's go to Mars and far beyond -  triple NASA's budget !   #space channel !!    - videos !!!

Offline

#3 2007-01-14 20:20:04

Michael Bloxham
Member
From: Auckland, New Zealand
Registered: 2002-03-31
Posts: 426

Re: Really big rockets

Yeah but these ones are based on current hardware.

The text came out fuzzy, so here it is again:

PARIS: Parallel Rocket Ignition System

- Standard 10m diameter tanks mounted in parallel.
- 7 RS-68b engines or equivalent under each tank.
- Up to 7 tanks can be clustered in parallel.
- All engines can be ignited and checked before lift-off.
- Propellant fed from one tank to an adjacent tanks engine.
- First stage burns quickly with 9 engines per tank.
- Second stage burns utilizing 5 engines per tank.
- Middle tank burns slowly on 3 engines all the way to orbit.


- Mike,  Member of the Clean Slate Society

Offline

#4 2007-01-18 06:42:11

Michael Bloxham
Member
From: Auckland, New Zealand
Registered: 2002-03-31
Posts: 426

Re: Really big rockets

Shuttle-Ares-Paris.jpg


- Mike,  Member of the Clean Slate Society

Offline

#5 2007-01-18 07:51:49

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 21,678

Re: Really big rockets

I like the big rockets Michael but as its Nasa doing it and not a conservative private space company focusing on cost I can see Nasa's cost being about 2 billion for Paris III and probably closer to 3 for the paris VII...

Offline

#6 2007-01-18 08:06:03

Michael Bloxham
Member
From: Auckland, New Zealand
Registered: 2002-03-31
Posts: 426

Re: Really big rockets

Yeah I know. What can ya do?  roll

Nevertheless, If we really needed a 300T booster, it can be seen that Paris III isn't terribly less efficient than current designs. Thought provokingly, it will still be significantly cheaper than the Shuttle, cost per pound. Although I concede that the one-time cost of developing the necessary support infrastructure might not be worth it.

Also, I'd imagine Paris III to come around 2030, after the moon has been explored with Ares V's and VII's. A mars mission will (finally) be on the cards then, and the current apollo-era support infrastructure will be starting to crumble. Also, something better and cheaper than the RS-68 might have popped up by then. Perhaps more significantly though, the US economy will be bigger.

BTW, if Paris III costs 2 billion, then Paris VII would cost 2*(7/3) = 4.7 billion. Although the cost per pound will be the same. Paris VII might be a good basis for a quick and dirty mega-booster, in the event of a killer asteroid prevention mission.


- Mike,  Member of the Clean Slate Society

Offline

#7 2007-01-18 08:25:41

Michael Bloxham
Member
From: Auckland, New Zealand
Registered: 2002-03-31
Posts: 426

Re: Really big rockets

Thinking about it now, Paris III might not require as much infrastructure change as you might think. First of all, without the payload shroud 'cap', the vehicle should just fit under the VAB doors . Also, without the monstrous weight of the SRB's, the two extra empty tanks should be easily carried on the transporter.

However, in order to fit through the narrow VAB doors, the vehicle will have to come out sideways, and therefore may require significant redesign of the MLP.


- Mike,  Member of the Clean Slate Society

Offline

#8 2007-01-18 08:39:10

Michael Bloxham
Member
From: Auckland, New Zealand
Registered: 2002-03-31
Posts: 426

Re: Really big rockets

To understand where I've got the payload figures from, let's compare Paris III with the Delta IV Heavy:

Delta IV Heavy Core Stage = 5.1m diameter x 40.8 m height = ~ 834 cubic meters volume.

Paris III Core Stage = 10m diameter x 100m height = 7857 cubic meters.

Considering the increased performance from propellant cross-feed, better tank mass efficiencies (bigger tanks), and the presumably higher ISP of future RS-68's, we could round this up to 10 times the Delta IV Heavy payload?

Damn, thats only ~270 tonnes. Oh well, that'll have to do.

Edit: My original estimates were made from this chart: http://www.boeing.com/defense-space/spa … ptions.pdf
From the chart I can guess 700 tonnes for the Paris VII is not too unreasonable, due to the increased staging.


- Mike,  Member of the Clean Slate Society

Offline

#9 2007-01-18 14:58:59

Michael Bloxham
Member
From: Auckland, New Zealand
Registered: 2002-03-31
Posts: 426

Re: Really big rockets

Shuttle-Ares-Paris-Development-Plan.jpg


- Mike,  Member of the Clean Slate Society

Offline

#10 2007-01-18 17:51:27

cIclops
Member
Registered: 2005-06-16
Posts: 3,230

Re: Really big rockets

blox3qe9.jpg

Why stop at the PARIS? this one is called the BLOXHAM. It's capable of lifting the VAB into LEO with the doors open or closed smile


Let's go to Mars and far beyond -  triple NASA's budget !   #space channel !!    - videos !!!

Offline

#11 2007-01-18 20:36:30

Michael Bloxham
Member
From: Auckland, New Zealand
Registered: 2002-03-31
Posts: 426

Re: Really big rockets

Mwahahaha! I shall take over the world!  wink


- Mike,  Member of the Clean Slate Society

Offline

#12 2007-01-18 23:41:17

Michael Bloxham
Member
From: Auckland, New Zealand
Registered: 2002-03-31
Posts: 426

Re: Really big rockets

Both the Paris III and Paris VII's middle tank, like the Shuttle ET, rides all the way to orbit, and, if fitted with a docking port, numbers of these could be assembled together to form large pressurized spaces.

Because the first stage burns so quickly on 9 engines, it does not attain astronomical altitudes and can be recovered with parachutes, and because it will not require heat shields it can be potentially reused.

This might save costs a bit.

I can imagine that, when a new core is built, it will be used on the first stage, and recovered a few times; eventually 'graduating' to the orbital middle tank.


- Mike,  Member of the Clean Slate Society

Offline

#13 2007-01-19 05:11:13

Michael Bloxham
Member
From: Auckland, New Zealand
Registered: 2002-03-31
Posts: 426

Re: Really big rockets

I found this interesting quote from 'kraisee' in the 'VSE -other alternatives' thread at the nasaspaceflight forums, in response to the insanely heavy Jupiter III launch vehicle:

TeamVision_Jupiter3.jpg

Each SRB segment masses about 150mT. The entire Saturn-V massed about the same as just two *segements* of an SRB.

Four segments (one booster) masses almost the same as the entire Apollo LUT (700mT). The two SRB's used by Shuttle mass MORE than the empty Saturn-V and LUT put together on the MLP - and that doesn't account for the 100mT orbiter, the 30mT External Tank and the typical 15mT payload.

Two SRB's already take the Shuttle stack to the limits of the Crawlers. Two extra segments and a launch tower already necessitate new Crawlers for the Ares-V program. The concrete structure at the Pads is only rated for about 1.5 times the mass of the Shuttle stack when fully fuelled prior to launch, so it could not handle the mass of something that vast.

As for the VAB, its is not the width. The depth of the work platforms do not stretch out anywhere near the new set of SRB's at the far end of the Jupiter-III. What exists now, could only be modified to process half of the vehicle without a ***major*** structural re-build of the main structure inside the 'walls' of the highbays.

And Juptier-III's launch would easily blow out windows all over the cities of Titusville, Cape Canaveral and Cocoa Beach. EPA have already specified that 11m lb thrust would be the maximum allowable at LC-39. J-III is well in excess of that. And if there were a bang on the Pad... Yikes.


- Mike,  Member of the Clean Slate Society

Offline

#14 2007-01-20 01:12:44

Michael Bloxham
Member
From: Auckland, New Zealand
Registered: 2002-03-31
Posts: 426

Re: Really big rockets

Here's another idea: Revive the F1 engine and put as many as you can under a 10m x 90m tank filled with RP-1/O2. Two of these will serve as the outer tanks of the Paris III. The middle tank will be the same as before (hydrogen/O2, 3 to 5 RS-68's).

Something like this should be about 4 or 5 times the weight of a fueled Saturn V, with a payload therefore of about 600 tonnes.

It'll still fit sideways through the VAB door, and be transportable on the crawler. However, like all launch vehicles bigger than an Ares V, it will still need a new pad.


- Mike,  Member of the Clean Slate Society

Offline

#15 2007-01-20 01:55:03

Michael Bloxham
Member
From: Auckland, New Zealand
Registered: 2002-03-31
Posts: 426

Re: Really big rockets

Here's another idea: Use the current Shuttle ET's in a Paris VII configuration. By my calculations, such a vehicle at its skinniest will just fit through the VAB door with about an inch either side...

Actually, a Paris V configuration would just fit through also.


- Mike,  Member of the Clean Slate Society

Offline

#16 2007-01-20 08:41:48

Michael Bloxham
Member
From: Auckland, New Zealand
Registered: 2002-03-31
Posts: 426

Re: Really big rockets

Here's what 'Paris VII Small', based on 8.4m x 80m tanks, might look like:

Paris-VII-Small.jpg

Again, if orientated correctly (turned 30 degrees from the one in the diagram), it will just squeeze through the VAB doors with about 3 inches either side.

This has got to be the biggest, most powerful rocket you could possibly fit through the VAB door, or carry on the crawler transporter, without significant modifications to either.

However, it will definately need a whole new pad (it will probably be self-supporting), and I'm not sure whether there is enough room inside the VAB to assemble it.

But if you needed a booster in the 500 tonne class, I doubt whether you could get any cheaper or faster than this baby...

Edit: Extended versions of the 10m Ares V tanks will also fit through the VAB doors in a Paris V configuration. Apparently, an 8.4m tank holds about 5/7ths of the amount of a 10m tank of the same length, so a 10m Paris V might have about the same payload as an 8.4m Paris VII.


- Mike,  Member of the Clean Slate Society

Offline

#17 2007-01-20 11:31:55

Michael Bloxham
Member
From: Auckland, New Zealand
Registered: 2002-03-31
Posts: 426

Re: Really big rockets

PARIS-Parallel-Ignition-System.jpg

The middle diagram is the potential arrangement for a Paris V configuration. Paris V, constructed with 10m tanks, will be only 20m wide at its narrowest point, so it will clear the VAB door easier than Paris VII with 8.4m tanks.

Here's a potential equivalent PARIS-Small system, with 5 RS-68's under each 8.4m tank:

PARIS-Small.jpg


- Mike,  Member of the Clean Slate Society

Offline

#18 2007-01-22 11:51:02

Dayton Kitchens
Member
From: Norphlet, Arkansas
Registered: 2005-12-13
Posts: 183

Re: Really big rockets

Couldn't the Energyia, expanded to its ultimate size have sent something  like 500,000 lbs. into LEO?

Offline

#19 2007-01-22 12:01:35

Michael Bloxham
Member
From: Auckland, New Zealand
Registered: 2002-03-31
Posts: 426

Re: Really big rockets

I heard about 200 tonnes, so yeah. If the 8.4m Paris VII used kerosene/oxygen, with either 7 RS-84's or 4 'energia' RD-170's underneath each tank, it might lift nearly 4 times that: maybe 900 tonnes.

Check out: http://cleanslatesociety.50megs.com/PARIS.html


- Mike,  Member of the Clean Slate Society

Offline

#20 2007-01-23 11:53:45

GCNRevenger
Member
From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: Really big rockets

Couldn't the Energyia, expanded to its ultimate size have sent something  like 500,000 lbs. into LEO?

I think thats a little exaggerated. Closer to 120-150MT probably.


"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw

The glass is at 50% of capacity

Offline

#21 2007-01-24 10:17:58

cjchandler
Member
From: canada
Registered: 2006-06-24
Posts: 138

Re: Really big rockets

Why not build the sea dragon? With all those motors that need to all run perfectly everytime, I think you would have a real reliablity problem. The sea dragon would probably be cheaper too.
http://www.astronautix.com/lvs/searagon.htm


Ad astra per aspera!

Offline

#22 2007-01-24 12:59:47

Michael Bloxham
Member
From: Auckland, New Zealand
Registered: 2002-03-31
Posts: 426

Re: Really big rockets

Yeah, everyone keeps mentioning the problems with having 49 engines. But I'm not so sure... They will all be started at the same time, and checked for performance before lift-off.

When was the last time an RS-68 failed during ascent anyway?


- Mike,  Member of the Clean Slate Society

Offline

#23 2007-01-24 18:20:35

GCNRevenger
Member
From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: Really big rockets

Its all about numbers

Say that there is a 0.05% chance that an RS-68 will fail, so the chance of engine failure on Delta-IV Heavy = 0.15% and Ares-V = 0.25% respectively, which is pretty small.

But for the 49 engine monster, its a about 2.5%, which is pretty significant, especially for an "all your eggs in one basket" megarocket.

So yeah, 50 engines is a problem. RS-68 hasn't failed, but it hasn't flown that many times either, and only once having to withstand the vibration from other engines so its track record isn't that long. Just the vibration from the other 40-odd engines might be enough to damage the turbo pumps or something too.

When the reliability of a rocket engine is in question, then it is only sane to assume the worst, and not the best. Of all the large liquid engines, only SSME has been shown to be reliable enough for such a "supercluster" rocket. All the others, the F-1/F-1A, RD-170, etc would have too high a risk of failure in such numbers I bet.

As your payload increases, unless you are shipping something cheap and your rocket is likewise cheap, then the reliability should increase likewise. Such a massive cluster of engines does the opposite.

SeaDragon, to its credit despite its absurd size, had only two engines and no turbo pumps at all.


"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw

The glass is at 50% of capacity

Offline

#24 2007-01-24 18:38:34

Michael Bloxham
Member
From: Auckland, New Zealand
Registered: 2002-03-31
Posts: 426

Re: Really big rockets

Why do you say only 0.05%? That seems pretty small. 2.5% failure rate would be about the same as the Shuttle, and they're still keen to put 7 eggs (no offence to the shuttle crew) in that basket.


- Mike,  Member of the Clean Slate Society

Offline

#25 2007-01-24 19:26:18

GCNRevenger
Member
From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: Really big rockets

I used the figure as an example of how a small risk for a small number of engines can be acceptable while a small risk for a large number of engines is not.

2.5% isn't acceptable, one of the core reasons why Shuttle is being eliminated three years from now. The decision to keep flying is, again, a numbers game; the chance the Shuttle will blow up in another dozen flights is acceptable, while a large number of flights is not.

The risk of one of the many engines blowing and the whole rocket CATOing with such a huge, valuable payload are unacceptable.


"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw

The glass is at 50% of capacity

Offline

Board footer

Powered by FluxBB