Author Topic: Do you believe in DIRECT?  (Read 45894 times)

Offline marsavian

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Re: Do you believe in DIRECT?
« Reply #40 on: 01/08/2008 12:11 AM »
I think Mike Griffin better start believing in DIRECT sooner rather than later because the chances of the most anti-Space Presidential candidate winning are getting stronger day by day and we probably won't even get Ares I let alone Ares V then ! Political reality is calling Mike and time to ensure Heavy Lift is assured before you sign off !

Offline HIP2BSQRE

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Re: Do you believe in DIRECT?
« Reply #41 on: 01/08/2008 02:13 AM »
I think people really have to look at what the US "might" get for the next 30 years:

1.  Direct---Takes the US to the Moon and beyound.
2.  EELV:  Great rocket---but to take the US to the moon?  Is it time for lego.
3.  Ares I:  Stuck in LEO for the next 30 years.

I am not saying Direct is the end all, but REALLY think what spend money today, we might be flying for the next 30 years.  If you want Ares fine, but in 5 years don't complain when we don't get it's big brother and we are stuck flying in LEO.

As to the point about people fearing for their jobs.  I agree---people will not want to upset the cart.  I work for the public service.  There are tons of rules about people not being discriminated againist for upsetting the boss.  You upset the boss, you will be BLACK LISTED.  You will not be getting ANY promotion, they will send you to the most remote spot that they can send you.  Your career will be over.  You may think I am joking, that it does not happen.

Then, go down to the local govt. office (SSI, DPSS, etc) and ask any worker what might happen if he goes against his/her Director/Big Boss.  That worker will have no nice toys to play with.

Offline Steven Pietrobon

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RE: Do you believe in DIRECT?
« Reply #42 on: 01/08/2008 02:37 AM »
As a hard-core space geek (who has written his own trajectory simulation programs for the Saturn V and Space Shuttle) and who has read the 130 page AIAA paper, its as obvious as the nose in front of my face that Direct is a much cheaper and easier solution for NASA in comparison to Ares-I/V. I voted number 4.

To those who don't "believe" that Direct is better, I suggest you go read Werner von Braun's book "The Mars Project". There you will learn nearly all you need to know for writing your own trajectory simulation program like I did. If you want to show that Direct won't work, do your own maths and crunch your own numbers. Go put in the hard yards that others have done. If you then find their numbers wrong, present your results. We'll all be interested in what you have to say.

Here's a summary of my analysis of Direct that I posted in another forum.

I read the whole paper (just about all of the 131 pages) and it is obvious that Direct is a much simpler and cheaper solution than Ares-I/V. Direct uses one vehicle that can launch either medium (41.8 t into 78x222 km, 28.5º orbit) with the Jupiter 120 or heavy (95.3 t into 56x222 km, 28.5º orbit) with the Jupiter 232. Note that 1 t = 1000 kg.

The main elements of Direct are the

1) Current 8.4 m diameter external tank (ET) modified to accept two or three crew-rated RS-68 engines operating at 100% thrust at the base and a forward skirt at the top
2) Existing four segment solid rocket boosters (SRB)
3) New Earth departure stage (EDS) with two J2-XD engines with standard turbo-pump

The Jupiter 120 has two RS-68 engines and no upper stage, while the Jupiter 232 has three RS-68 engines and an upper stage.

The main elements of Ares-I/V are

1) New 10 m diameter main stage with five crew-rated RS-68 engines operating at 106% thrust.
2) SRBs modified with five segments.
3) New EDS with one J2-X engine with modified turbo-pump for increased thrust
4) New Ares-I upper stage with one J2-X engine

Ares-I uses one modified SRB and the new upper stage. Ares-V uses the new core, two modified SRBs and the new EDS. Ares-I/V will require extensive pad and vehicle assembly building (VAB) modifications to accept two very different vehicles. The footprint for both Jupiter 120 and 232 vehicles are the same and is also similar to shuttle since the same ET diameter tank is used. This implies much less modifications are required to the pads and VAB.

Current performance for the Ares-I is 25 t (the same as Delta-IV Heavy) and 130 t for Ares-V. The Ares-V will first launch the Lunar surface access module (LSAM) and wait for the Ares-I to launch the crew exploration vehicle (CEV). The CEV docks with LSAM and the EDS fires to go the Moon. If the CEV fails to launch due to delays, the EDS and LSAM are lost. The total payload mass in LEO is 155 t. The trans Lunar injection (TLI) payload is 59.4 t.

In Direct, a Jupiter 232 is first launched only carrying the EDS. The payload here is 98.3 t of propellant. A second Jupiter 232 is launched carrying the CEV, LSAM and 20.5 t of liquid oxygen (LOX) in a tank under the LSAM. This stack docks with the EDS and the LOX is transferred to the EDS. The EDS stage is lengthened by 0.87 m for the additional liquid hydrogen. If the second Jupiter 232 fails to launch due to delays, then only the EDS is lost, saving an expensive LSAM. The total payload mass into LEO is 190 t, 22.5% greater than Ares-I/V. The TLI payload is 70.4 t, 18.5% greater than Ares-I/V.

For an Apollo 9 like test mission, where the LSAM and CEV are tested in low Earth orbit (LEO), Ares-I/V requires that both an Ares-V and an Ares-I launch. For Direct, a single Jupiter 232 is launched carrring the CEV, LSAM and extra LOX. The docking and LOX transfer can be practised with the EDS that was also launched.

For missions to LEO, the Jupiter 120 can carry the CEV, along with an additional 24 t of payload, replicating the capability of the existing shuttle system. This extra payload can also be used for carrying extra payload to the International Space Station, servicing missions to the Hubble Space Telescope, new larger space telescopes, and other new missions to the inner and outer planets.

In the early 1960's, Werner von Braun and the NASA team made much more difficult choices. They had to decide to use liquid hydrogen in the upper stages while that technology was in its infancy as well as deciding to use Lunar orbit rendezvous which was even more risky since that had never been done before. With Direct, the new technology is LOX transfer, in which there will be plenty of time to practice. The gain is a much more capable launch system that will be much more cheaper and easier to develop. Unfortunately, the current NASA management seems to be stuck in its ways.
Akin's Laws of Spacecraft Design #1:  Engineering is done with numbers.  Analysis without numbers is only an opinion.

Offline jongoff

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Re: Do you believe in DIRECT?
« Reply #43 on: 01/08/2008 04:14 AM »
I voted #4.  I don't think we need or even want a Shuttle Derived solution, but that doesn't mean that I think DIRECT won't work with some relatively minor changes.  

I've also seen the same information that the DIRECT team used for their mass numbers for the Jupiter upper stage.  The datasheet they used was based on several years worth of work by LM and NASA on developing a follow-on upper stage to the existing Centaur stage.  The numbers agree, and are conservative.  If you use their mass relations they gave you can back out the current mass of existing Centaur stages to a high degree of fidelity, and using the new FSW techniques they've been perfecting over the last several years, they expect to be able to beat many of those numbers handily.  As far as I can tell, the numbers Chuck and Ross used for that stage are pretty solid.

I'd still prefer a commercial propellant depot, no heavy lift vehicle, and NASA getting out of the earth-to-orbit launch business and acting as a customer instead.  But that isn't because I think DIRECT is technically broken or that their cost estimates for DIRECT are out of whack.  It's because I actually want to see a real, thriving cislunar economy.  

~Jon

Offline luke strawwalker

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RE: Do you believe in DIRECT?
« Reply #44 on: 01/08/2008 04:16 AM »
When it's all said and done, what I'm afraid is going to happen is:

1) Ares I is cancelled after considerably more time, effort, and money is wasted when the schedule slips completely off the right side of the page and costs become obviously headed out of hand, and performance results become more and more dubious.  

2) This will spell the certain death of Ares V, as there will be NO money or confidence that it can be developed and by that time the shuttle hardware and infrastructure will be gathering dust and becoming museum pieces.   This will spell the death of heavy lift for the foreseeable future.

3) Orion will be so gutted by it's constant starvation diet trying to make the pointless Ares I work that it won't be capable of going anywhere.  It will be slapped on an EELV so the US can claim to be a spacefaring nation; after all we HAVE to have a capability that the Russians and Chinese have, but it will be hollow; more 'guys in a can' in LEO for the next 30 years.  

4)  The WORST thing that could happen is if by some miracle Ares I actually flies, but no money left for Ares V, LSAM, EDS, etc.  There won't even be money left to develop something like a Delta or Atlas upgrade to 50-70 ton launchers that actually COULD reduce the number of launches to something feasible.  

5) In the end, Ares I is going to cost SO much to develop what a Delta IV Heavy can already do that there just won't be any money to design and build LSAM's, 33 foot cores, EDS's; let alone any lunar base elements.  If by some miracle Ares I doesn't eat it all up, Ares V will, and the launch costs will prove SO high that there just isn't any money left to do anything.  All dressed up and nowhere to go, so to speak.  

6) If Ares I schedule slides off the right side of the paper, or the costs become exhorbitant, so much time and effort will be wasted that the shuttle infrastructure all starts gathering dust or turns into museum pieces, and the capability for something like DIRECT, which COULD have been done, will be lost forever.  Truer words were never spoken; that if NASA wants heavy lift, they have to develop the heavy lift vehicle FIRST.  With Ares I/V architecture that is NOT possible, (political suicide) but with DIRECT it IS possible, which would make the whole thing possible, since your first rocket, with a few gradual development programs, can get you to the moon.  Ares I sucks these resources away into a black hole to do something we can already do on another vehicle.  

I think in a couple years or so we'll be right back where we started, chalking up the VSE alongside Bush I's SEI and other dead space programs, and staring at Ares I and V plans alongside other cancelled projects like Dyna-Soar, X-33, OSP, NLS, Shuttle-C, etc. and wondering how we ended up with Gemini on Geritol instead of Apollo on Steroids.  Maybe I'm just pessimistic, but everything is circular, and I see the same old same old all over again, all talk, big dreams, little $$$, slipping schedules, unrealistic expectations, huge expenses, deteriorating performance, increasing problems, and wasted opportunities.  But then what should one expect... it is the government after all...  (sigh)  JMHO!  OL JR :)
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Offline Bruce H

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Re: Do you believe in DIRECT?
« Reply #45 on: 01/08/2008 05:39 AM »
Quote
savuporo - 7/1/2008  8:55 AM

Quote
MATTBLAK - 7/1/2008  1:51 AM
And it's for this reason that many of them are keeping quiet -- they may not actually lose their jobs for speaking out against Ares 1
I have nothing against DIRECT, and voted for it, but this sounds awfully like a conspiracy theory, which i have become to dismiss immediately, unless some solid proof is supplied.
Without any actual evidence of voice suppression in this matter, i would guess they are quiet because they feel theres nothing to shout about.

No conspiracy. Simple logic which you can apply to most jobs with major corporations.

I believe a lot of pro-Direct votes here relate to the commendable communication of those behind it. It's hard not to feel involved (a basic foundation of this site) and passionate about seeing what is a paper rocket growing out of its Marshall ashes.

Take Ares I. NASA feed the public with dismal efforts of PR, and continue to take the view that it's their job to protect information leaking out, rather than spreading the info and getting public interested.

Offline JIS

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RE: Do you believe in DIRECT?
« Reply #46 on: 01/08/2008 06:03 AM »
Quote
Steven Pietrobon - 8/1/2008  3:37 AM

The main elements of Direct are the

1) Current 8.4 m diameter external tank (ET) modified to accept two or three crew-rated RS-68 engines operating at 100% thrust at the base and a forward skirt at the top
2) Existing four segment solid rocket boosters (SRB)
3) New Earth departure stage (EDS) with two J2-XD engines with standard turbo-pump

The Jupiter 120 has two RS-68 engines and no upper stage, while the Jupiter 232 has three RS-68 engines and an upper stage.

The main elements of Ares-I/V are

1) New 10 m diameter main stage with five crew-rated RS-68 engines operating at 106% thrust.
2) SRBs modified with five segments.
3) New EDS with one J2-X engine with modified turbo-pump for increased thrust
4) New Ares-I upper stage with one J2-X engine

....

In Direct, a Jupiter 232 is first launched only carrying the EDS. The payload here is 98.3 t of propellant. A second Jupiter 232 is launched carrying the CEV, LSAM and 20.5 t of liquid oxygen (LOX) in a tank under the LSAM. This stack docks with the EDS and the LOX is transferred to the EDS.

Oops. You haven't mentioned that Direct needs a new element:
4) New extra tank carrying liquid oxygen, extra docking adapter and support for propellant transfer. Will it be carried all the way to lunar orbit or will be jettisoned? Also docking manouevre of 90t stack will require more propellants and stronger RCS than just 20t Orion.

Also the use of RS-68B is actually an advantage as it improves reliability and keeps commonality with future EELV. It will be wise for DIRECT to accept this option. Otherwise it would have to human rate both versions. It's step in the right direction.
'Old age and treachery will overcome youth and skill' - Old Greek experience

Offline texas_space

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Re: Do you believe in DIRECT?
« Reply #47 on: 01/08/2008 07:32 AM »
Quote
HIP2BSQRE - 7/1/2008  9:13 PM

I think people really have to look at what the US "might" get for the next 30 years:

1.  Direct---Takes the US to the Moon and beyound.
2.  EELV:  Great rocket---but to take the US to the moon?  Is it time for lego.
3.  Ares I:  Stuck in LEO for the next 30 years.

I am not saying Direct is the end all, but REALLY think what spend money today, we might be flying for the next 30 years.  If you want Ares fine, but in 5 years don't complain when we don't get it's big brother and we are stuck flying in LEO.

This hits the point exactly.  What we do now is what we're likely to be "stuck" with for the next 20-30 years.  So get it right now or be ready to hear much complaining later.

Ares-I may work technically, but it's a lousy waste of money and time.  This gets you the Moon and other places, but only if you get the Ares-V too (good luck with that).

EELV's have promise, but I think to truly make it viable (ie fewer launches) that will require new development to get more than 25T to orbit.  So much for commercial off the shelf.

DIRECT probably needs work to turn into reality, but I believe that it has the best chance to enable human exploration of the solar system in the 21st century.  So I voted for it under option 4.  If we get to the Moon and other places with a different system, then great!  But I tell you, I don't see it happening.
"We went to the moon nine times. Why fake it nine times, if we faked it?" - Charlie Duke

Offline kraisee

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Re: Do you believe in DIRECT?
« Reply #48 on: 01/08/2008 07:45 AM »
Quote
JonSBerndt - 7/1/2008  7:10 PM

Quote
mike robel - 7/1/2008  4:00 PM

After due thought, I had to vote for I am not qualified to offer an opinion.  BUT, as I have learned that most proposals change after they are accepted by the government, I have to think that  current option 4, it would need major changes to be accepted by NASA is most likely.

Chuck or Ross - maybe you could remind us to what degree DIRECT is a derivative of the NASA/MSFC LV24/25 concept? Reading some of these responses, it seems that some of the "pedigree" of DIRECT is being overlooked.

Jon

We did have access to all of the LV-24/25 trade studies done for ESAS.   They are, in large-part, based on NLS before it (the trade studies for both share quite a bit in common - though LV-24/25 is quite a bit updated) , but we didn't really know all that much about NLS itself until this last summer and it's only very recently that I've personally seen specifications and trade studies on NLS to review.

Anyhow, the LV-24/25 trade studies formed the primary backbone for developing all of DIRECT v1.0 - although I put my hand up as responsible for making the stupid mistake of using an engine which does not yet exist there and allowed FUD in.   Although we now have *proof* that we were actually correct, its way too late now - the disinformation did it's intended job of discrediting us at the end of 2006.

But we flipped that on its head and addressed each of the points made against us in order to come up with something better.

DIRECT v2.0 went right back to the original drawing-board, again including LV-24/25 at its heart.   We started with nothing more than a passing resemblance to the previous version, and the utter determination to pack the whole system - performance, cost and schedule alike - with extra margins everywhere we could.   And this time, we made quite sure not to bank on any costly "leaps of technology" wherever possible.   The one exception being that we need to use the evolved version of the Apollo J-2 - the J-2X - eventually for our Upper Stage.   Although even here we only baselined to the lower specification 274,000lb thrust J-2X"D" version, not the full 294,000lb thrust version currently baselined for both Ares-I and Ares-V.   While we have no reason to believe the 294,000lb version is unlikely, we still aren't trying to prove anything and just don't need the higher-stressed variant of this engine to make our concept work.

We assume the SRB's remain *absolutely* unchanged from the ones flying today.

We assume the RS-68 is precisely the same as the ones flying today, even though a more powerful version is in development - we aren't stupid enough to count those chickens until they are actually hatched - when the 106% variant of the RS-68 is actually ready for flight testing, we will switch to it, but until then we want to make sure we can do what we claim even if it gets itself canceled for any reason and that performance boost is denied.   Engine performance increases are really nice.   Engine performance decreases hurt - a lot.

So we now have a system which deliberately aims to re-use as much existing hardware, manufacturing, processing and launch infrastructure as possible with either no changes, or with the minimum possible extent of changes in order to reduce costs and speed development while still ticking the appropriate performance, cost, schedule, workforce, political and national pride boxes.   We believe we have a solution with a green check mark in every one of those requirement boxes now.   No, it's not a "clean sheet" design.   No, it's not anything totally spectacular.   It's simply what we have, turned into what we *need* with the minimum of effort to get the job done.


But the real "pedigree" comes from the 57 dedicated engineers, from NASA, Boeing, Lockheed Martin, Pratt & Whitney/Rocketdyne, United Launch Alliance and a few other contractors too.   All of whom have volunteered their valuable skills and time, free of charge or recognition, and at possible risk to their careers, to help us put together the DIRECT proposals.   They have, and always will be, the real talent here and it has been an absolute privilege to talk to, work with and learn from, all these amazing people - every single one.

Ross.
"The meek shall inherit the Earth -- the rest of us will go to the stars"
-Robert A. Heinlein

Offline kraisee

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Re: Do you believe in DIRECT?
« Reply #49 on: 01/08/2008 08:12 AM »
Well said Luke.   I think you're dead on the mark.

Sadly, with the current reticence of management to shift away from the gads-awful Ares-I, I think you are also predicting the future all-too accurately.

Ross.
"The meek shall inherit the Earth -- the rest of us will go to the stars"
-Robert A. Heinlein

Offline JIS

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Re: Do you believe in DIRECT?
« Reply #50 on: 01/08/2008 08:58 AM »
Quote
kraisee - 8/1/2008  8:45 AM

DIRECT v2.0 went right back to the original drawing-board, again including LV-24/25 at its heart.   We started with nothing more than a passing resemblance to the previous version, and the utter determination to pack the whole system - performance, cost and schedule alike - with extra margins everywhere we could.  

If you have LV-24/25 numbers maybe you can explain why the performance of ESAS LV-29 is so pathetic compared to DIRECT configuration.
LV-29 is using 4seg SRBs, core with 3 x RS-68 and second stage with 4 x J-2s. Lift capability is 108mT to LEO. Net payload 92mT.
I looks like the only difference is less J-2 engines and higher payload. In reality the difference must be in dry weight of stages. It would be interresting to compare these numbers. Do you have these numbers and can you show them?
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Offline Nathan

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RE: Do you believe in DIRECT?
« Reply #51 on: 01/08/2008 09:00 AM »
Quote
rsp1202 - 8/1/2008  12:52 AM

This whole thread is based on one person's negative bias. What a joke. It's beneath this forum.

I'm with you. Can we add that as an option?
Given finite cash, if we want to go to Mars then we should go to Mars.

Offline clongton

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RE: Do you believe in DIRECT?
« Reply #52 on: 01/08/2008 12:07 PM »
Quote
JIS - 8/1/2008  2:03 AM

Also the use of RS-68B is actually an advantage as it improves reliability and keeps commonality with future EELV. It will be wise for DIRECT to accept this option. Otherwise it would have to human rate both versions.
JIS;
You should know better. There won’t be 2 versions of the RS-68, only one. Currently, the RS-68 is flying hardware, and the RS-68B, as you call it, is a paper engine. If and when that engine becomes real hardware, the existing RS-68 will be retired and then the new one will be used exclusively by all launch vehicles that employ the RS-68.
Chuck - DIRECT co-founder
I started my career on the Saturn-V F-1A engine

Offline JIS

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RE: Do you believe in DIRECT?
« Reply #53 on: 01/08/2008 12:50 PM »
Quote
clongton - 8/1/2008  1:07 PM

Quote
JIS - 8/1/2008  2:03 AM

Also the use of RS-68B is actually an advantage as it improves reliability and keeps commonality with future EELV. It will be wise for DIRECT to accept this option. Otherwise it would have to human rate both versions.
JIS;
You should know better. There won’t be 2 versions of the RS-68, only one. Currently, the RS-68 is flying hardware, and the RS-68B, as you call it, is a paper engine. If and when that engine becomes real hardware, the existing RS-68 will be retired and then the new one will be used exclusively by all launch vehicles that employ the RS-68.

Yes, I agree. Sorry for not making it clear. NASA and AF want RS-68B. This is the version to be manrated. RS-68 is not going to be manrated. RS-68B includes changes to turbine nozzles, injector, ablative nozzle, different start-up etc. The effect is that they have 106% thrust level, longer burn time and they are manrateable. RS-68B for Ares V will be manrated (extra equipment) and have some minor mods to fly in the bundle.
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Offline TrueGrit

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Re: Do you believe in DIRECT?
« Reply #54 on: 01/08/2008 04:03 PM »
just to note...  Delta IV Heavy with the upgraded RS-68's will acheive 27,000kg to ISS.  Two fairly simple developments beyond this would the additonal of GEM's and the development of the ULA advanced upperstage concept which would increase performance to ~40,000kg.  Beyond that I think the you need to go to either a 5-body booster, or more preferable 7-m booster with twin RS-68s.  But this is where Jupiter/DIRECT starts to look more appealing...

Offline clongton

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Re: Do you believe in DIRECT?
« Reply #55 on: 01/08/2008 04:36 PM »
Quote
TrueGrit - 8/1/2008  12:03 PM

just to note...  Delta IV Heavy with the upgraded RS-68's will achieve 27,000kg to ISS.  Two fairly simple developments beyond this would be the addition of GEM's and the development of the ULA advanced upper stage concept which would increase performance to ~40,000kg.  Beyond that I think the you need to go to either a 5-body booster, or more preferable 7-m booster with twin RS-68s.  But this is where Jupiter/DIRECT starts to look more appealing...
Which is exactly why we decided to set the bottom tier performance level of the Jupiter at about where the top tier performance of the EELV was. For example the Jupiter-120 has an *advertised* capacity to send 47mT into LEO. This was a deliberate decision to *NOT* compete with the EELV family. The nation has invested considerable treasure in the development of that family of launch vehicles and the DIRECT team is hopeful that a properly led VSE would maximize the use of the EELV performance envelope by assigning flights to it that are well suited to its capacities such as launching Orion on LEO missions with a SM properly sized for that, resupplying propellant depots located in several places in support of multiple kinds of VSE missions, logistics resupply to orbital outposts and the lunar surface and continuing to send probes, orbiters and robotic landers to the lunar surface and to the planets and their moons. Unlike the Heavy-Lift-Only crowd *and* the EELV-only crowd, we believe there is a role for both and the nation is best served by utilizing, to the maximum extent possible, the capabilities of both the EELV and the Heavy Lift.
Chuck - DIRECT co-founder
I started my career on the Saturn-V F-1A engine

Offline brihath

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Re: Do you believe in DIRECT?
« Reply #56 on: 01/08/2008 04:43 PM »
I voted for number 4.   I'm not in the space industry, but I was responsible for making sure a SAC bomb wing kept its planes flying and on SIOP alert when I was in the AF.  I always had a credo that if it looks like it should fly, it generally should fly.

The DIRECT concept builds on 25+ years of Shuttle experience, so much of the vehicle has been flight proven and it minimizes the design changes from STS, while ARES 1 is a completely different story.  If we want to minimize the manned spaceflight gap, we should go with what we know and minimize the risks, especially in the current budget environment.  It's not really that new, as shuttle derived concepts have been bandied about for years.

My only concern with this answer is that a "peer-reviewed" process could become just another bureaucratic dead end that kills a potentially successful flight program.  It's been done before.

Finally, anything we do regarding the manned spaceflight gap should minimize any reliance we have on Russia.  I know we have developed an excellent record of cooperation, but the political winds can change in a heartbeat, and we will be left out in the cold.  It should definitely NOT be something we plan on doing.

Offline TrueGrit

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Re: Do you believe in DIRECT?
« Reply #57 on: 01/08/2008 05:11 PM »
I've got to disagree with the idea that cargo and manned were a cause of either shuttle failure.  The whole purpose of manned spaceflight isn't to see if we can get there.  We've got get beyond the concept of manned spaceflight being one based on "flag planting", and one based on advancing our knowledge.  Whether it be monitoring the climate, to investigating growing crystals in microgravity, or investigating the geology of other planetary bodies.  The goal of having people in space isn't an end in and of itself, but what they can do once there.  For example look at the pilots who fly P-3's into a hurricane...  The plane outiftted for science, not for the thrill of playing daredevil.  The Columbia mission cargo was exactly that, one of scientific investigation...  Whether what they were doing couldn't be better done by a unmaned vehicle, or was worth their lives isn't the question.  The fact is there is some science that is worth the risk, and some that is best done by a human in the loop.  Therefore by designing a vehicle who's only purpose is to put people in space completely forgets the reason why we're are investing billions of tax money on the space program.  Ares I not only redundant with existing capability, but completely forgets about the whole purpose of having a public space agency...  To return that investment back to the general public.  Without science package to go along with man in space it's nothing more than daredevil ride...  And like bungee jumping not something for the government to be investing in.

Offline khallow

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Re: Do you believe in DIRECT?
« Reply #58 on: 01/08/2008 06:48 PM »
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TrueGrit - 8/1/2008  10:11 AM

I've got to disagree with the idea that cargo and manned were a cause of either shuttle failure.  The whole purpose of manned spaceflight isn't to see if we can get there.  We've got get beyond the concept of manned spaceflight being one based on "flag planting", and one based on advancing our knowledge.  Whether it be monitoring the climate, to investigating growing crystals in microgravity, or investigating the geology of other planetary bodies.  The goal of having people in space isn't an end in and of itself, but what they can do once there.  For example look at the pilots who fly P-3's into a hurricane...  The plane outiftted for science, not for the thrill of playing daredevil.  The Columbia mission cargo was exactly that, one of scientific investigation...  Whether what they were doing couldn't be better done by a unmaned vehicle, or was worth their lives isn't the question.  The fact is there is some science that is worth the risk, and some that is best done by a human in the loop.  Therefore by designing a vehicle who's only purpose is to put people in space completely forgets the reason why we're are investing billions of tax money on the space program.  Ares I not only redundant with existing capability, but completely forgets about the whole purpose of having a public space agency...  To return that investment back to the general public.  Without science package to go along with man in space it's nothing more than daredevil ride...  And like bungee jumping not something for the government to be investing in.

Let's also keep in mind that science while of some value, isn't in itself going to lead to sustainable activities in space. For that you need someone making money from doing something in space.
Karl Hallowell

Offline William Barton

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Re: Do you believe in DIRECT?
« Reply #59 on: 01/08/2008 07:01 PM »
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khallow - 8/1/2008  2:48 PM

Quote
TrueGrit - 8/1/2008  10:11 AM

I've got to disagree with the idea that cargo and manned were a cause of either shuttle failure.  The whole purpose of manned spaceflight isn't to see if we can get there.  We've got get beyond the concept of manned spaceflight being one based on "flag planting", and one based on advancing our knowledge.  Whether it be monitoring the climate, to investigating growing crystals in microgravity, or investigating the geology of other planetary bodies.  The goal of having people in space isn't an end in and of itself, but what they can do once there.  For example look at the pilots who fly P-3's into a hurricane...  The plane outiftted for science, not for the thrill of playing daredevil.  The Columbia mission cargo was exactly that, one of scientific investigation...  Whether what they were doing couldn't be better done by a unmaned vehicle, or was worth their lives isn't the question.  The fact is there is some science that is worth the risk, and some that is best done by a human in the loop.  Therefore by designing a vehicle who's only purpose is to put people in space completely forgets the reason why we're are investing billions of tax money on the space program.  Ares I not only redundant with existing capability, but completely forgets about the whole purpose of having a public space agency...  To return that investment back to the general public.  Without science package to go along with man in space it's nothing more than daredevil ride...  And like bungee jumping not something for the government to be investing in.

Let's also keep in mind that science while of some value, isn't in itself going to lead to sustainable activities in space. For that you need someone making money from doing something in space.

If anyone ever successfully demonstrates a way to make money from manned space travel, we won't have to worry about sustainable activities in space again. They'll just happen (like comsats, for instance). In addition to thinking up comsats, Arthur Clarke once wrote a story suggesting a good way to make money from manned space travel would be producing and broadcasting pornography from space. Sort of like making money off the Internet...

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