DIRECT v3.0 - Thread 1

[mike robel]

Converting to metric is going to kill somebody someday 

Well, then let's convert to metric once and for all. The rest of the world has already done so...

we're traditional English/Imperial here.  get over it. 

If you'd ever worked engineering problems.. you'd realize metric really does simplify any analysis work.  And simplify interacting with international partners to boot.  Auto Industry realized that and switched 20 years or so ago.

I'm an Army Officer, we think in gallons, meters, klicks, and kph.  However, some other army people think in pounds, knots, and feet.

While working on our battle simulation, we made the decision to have everything inside be in metric, but for display to the users we had to have English/Imperial.

I am comfortable in both.  When I scratch build modes, I usually convert everything to metric.  For real distances I think in both and convert all the time.

It ain't the governments place to tell us which system to use.  If an industry wants to switch, they can go right ahead. 

[cro-magnon gramps]

to be noted, that Depots and PT is not in the baseline of Direct, but is on the wish list for Future Vision, but does feed into Direct's capabilities and strong points...

I'd just like to clarify that Propellant Depot's actually ARE on our baseline -- but they are for Phase 3 of our plans, not Phase 2.   Let me explain:-

Phase 1:   Close the Gap
Beginning Around:   2013

- Jupiter-130 to ISS, 20mT Orion + 40mT Payload

- Jupiter-130 for Hubble Servicing

- Jupiter-130 + Delta Heavy Cryogenic Upper Stage for "Apollo 8"-style mission

- Jupiter-130 (with or without DHCUS) available for large ~75mT IMLEO Science Missions


Phase 2: Initial Lunar Exploration
Beginning Around:   2018

- Jupiter-24x Dual-Launch Lunar Mission, No Propellant Transfer, ~80mT thru TLI

- Jupiter-24x Dual-Launch NEO Mission, No Propellant Transfer, Performance TBD

- Jupiter-24x Three-Launch Phobos Mission, No Propellant Transfer, Performance TBD

- Jupiter-130 (with or without DHCUS) available for large ~75mT IMLEO Science Missions

- Jupiter-24x available for very large ~100mT IMLEO Science Missions

NOTE:   Lunar mission hardware is actually designed with Mars in mind


Phase 3: Advanced Exploration
Beginning Around:   2022

- Jupiter-24x Single-Launch Lunar Missions, EDS (and LSAM?) would be re-fueled in LEO from a commercially supplied Depot, payloads greater than 100mT are possible thru TLI

- Jupiter-24x Single-Launch NEO Missions, EDS would be re-fueled in LEO from a commercially supplied Depot, payloads greater than 100mT are possible.

- Jupiter-24x Dual-Launch Phobos Missions, EDS would be re-fueled in LEO from a commercially supplied Depot, payloads greater than 200mT are possible.

- Jupiter-24x Dual-Launch Mars Missions, EDS and Lander launched dry and both are fueled in LEO using Depot supplied by both commercial suppliers and international partners.   IMLEO would be in the ~1,000mT class.

- Jupiter-24x Jovian Missions using Depot located either in LEO or at EML-2, depending upon the availability of Lunar ISRU.   Exact mission profile TBD.   IMLEO TBD.

- Jupiter-130 (with or without DHCUS) available for large ~75mT IMLEO Science Missions

- Jupiter-24x available for very large ~100mT IMLEO Science Missions

- Jupiter + Depot available for extremely large >200mT IMLEO Science Missions


Phase 2 is primarily designed as a 'stepping stone' to get from ISS to the full architecture, instead of trying to make a single "giant leap" straight from LEO to the full capability architecture.

Phase 2 'could' be skipped, but we think that from both a technological risk, from a cost/schedule risk and from an overall Programmatic risk stand-point, it is a better approach to include it as a 'stepping stone'.

Ross.

I stand corrected... this I am seeing then as the Grand Vision, no... Thankyou Ross...

[mike robel]

I say scrap the LAS, scrap the melting parachutes, scrap the sustainer motor. Use the weight savings to add reactive armor to the Orion and plow through the debris to escape to LEO. Then launch a rescue mission from the ISS. That’s how John Wayne would handle it.

[just kidding]

I say bring back the F-1!!!  2 LRBs on each side of the core, 260 INCH diameter, 2 F-1s each.  that'll get your blood pounding and do away with those propellent chunks!

[ar-phanad]

Just thought it was an interesting view.  Probably cure more headaches than it’d cause to adopt SI units here in the US, don’t get me wrong.  But the people the quickest to advocate that I don’t think really understand the flip side to it.

You can make it sound as complicated as possible, if that's what you want to stick with.  But if you really want to convert, the way to do it is to make it a policy that all "new" stuff gets done in Metric, and only "legacy" stuff is maintained in Imperial units.  I can guarantee you that if this approach was taken (and enforced), then pretty soon 90% of everything would be in Metric.

And for old farts (like me) who can't adapt, well, get used to doing conversions in your head.

We've been converting to Metric since I was in grade school.  Let's get it over with!

Mark S.

Sorry this is getting so far OT, but I wanted to point out that xkcd has long since solved all our problems:

http://imgs.xkcd.com/comics/converting_to_metric.png

[Lancer525]

I say bring back the F-1!!!  2 LRBs on each side of the core, 260 INCH diameter, 2 F-1s each.  that'll get your blood pounding and do away with those propellent chunks!

Great idea, Mike.

Except for the fact that the F-1 would have to be completely and totally redesigned from the beginning, all over again. Or, one of the existing museum pieces could be disassembled piece by piece, part by part, and a full set of working drawings and detail drawings would have to be made, not to mention materials testing, static testing, and all the other associated engineering would have to be re-done from scratch, because all the plans, drawings, technical information and everything related to the engine was destroyed way back when STS was still in the proposals phase.

[ar-phanad]

Sorry, didn't realize the context (I was using my iTouch at the time, and I didn't read the previous page of comments).

I was referring to Plume Impingement at the Base of the vehicle.

For confirmation:   There are no concerns about the LAS impinging on the vehicle below the Orion in the case of any aborts.

Ross.

Ross, it occurred to me shortly afterwards that you were actually in the audience at the time. That would explain the confusion.

Thanks for clearing that up, though; one more thing we wouldn't have to worry about.

Jesse

[Idol Revolver]

I say bring back the F-1!!!  2 LRBs on each side of the core, 260 INCH diameter, 2 F-1s each.  that'll get your blood pounding and do away with those propellent chunks!

Great idea, Mike.

Except for the fact that the F-1 would have to be completely and totally redesigned from the beginning, all over again. Or, one of the existing museum pieces could be disassembled piece by piece, part by part, and a full set of working drawings and detail drawings would have to be made, not to mention materials testing, static testing, and all the other associated engineering would have to be re-done from scratch, because all the plans, drawings, technical information and everything related to the engine was destroyed way back when STS was still in the proposals phase.

I have much hope for LRBs as an eventual upgrade to DIRECT or NSC. Would need development of a new engine though, since that is would re-building the F-1 would be analogous to anyway. Why does everyone like the idea of resurrecting  it so much anyway? I seem to see similar ideas a lot.

[Lancer525]

I have much hope for LRBs as an eventual upgrade to DIRECT or NSC. Would need development of a new engine though, since that is would re-building the F-1 would be analogous to anyway. Why does everyone like the idea of resurrecting  it so much anyway? I seem to see similar ideas a lot.

Probably because it was the biggest, most powerful rocket engine ever built at the time. We're all enamoured of really huge, powerful, fire-breathing, smoke-belching, rumbly-thundering machines. Arrr, arrr, arrh, arrrrough! 

[ugordan]

all the other associated engineering would have to be re-done from scratch, because all the plans, drawings, technical information and everything related to the engine was destroyed

That is a myth. Blueprints on the F-1 exist as the Saturn V engines were recognized to be the most valuable aspects of the vehicle for the future, as much as possible of their documentation was preserved.

That said, the tooling and manufacturing capability isn't there anymore and ideas of restarting F-1(A) production were floated around several years ago. IIRC the cost to restart production was estimated at $0.5 billion then-year dollars.

Much more here: http://www.thespacereview.com/article/588/1

EDIT: corrected estimated cost from article.

[ar-phanad]

I have much hope for LRBs as an eventual upgrade to DIRECT or NSC. Would need development of a new engine though, since that is would re-building the F-1 would be analogous to anyway. Why does everyone like the idea of resurrecting  it so much anyway? I seem to see similar ideas a lot.

Probably because it was the biggest, most powerful rocket engine ever built at the time. We're all enamoured of really huge, powerful, fire-breathing, smoke-belching, rumbly-thundering machines. Arrr, arrr, arrh, arrrrough! 

I'll second that! And maybe an LRB would solve the debris cloud problems - the thought occurred to me a while back, too. Just hard to promote that idea at the onset, since (aside from all-new manufacturing aspect) we're trying to keep the infrastructure intact.

Might be nice someday, though.

Jesse

[Eerie]

Judging by Energia boosters, 4 Falcon-9 first stages would do just fine.  Also, they are already human-rated.

[Idol Revolver]

Judging by Energia boosters, 4 Falcon-9 first stages would do just fine.  Also, they are already human-rated.

You'd need to redesign the ET, since it only currently has two attachment points.

[brihath]

Judging by Energia boosters, 4 Falcon-9 first stages would do just fine.  Also, they are already human-rated.

They are?  I didn't know that.  Rated to what standard?

[MP99]

Ross,

Quick question that's probably been answered before.  From a manufacturing standpoint, is there any difference between the J-130 and J-24x cores?  Meaning, at Michoud would they just roll the exact some core off the assembly line, then at the VAB they put it together with the engine and upperstage config they want?
Or are there actually core differences between the two that would be manufactured a bit different at Michoud.?

Ross/Chuck have said that they want a core to come off the production line so it can be fitted with 3 engines for J-130, or 4 engines and an upper stage to make J-24x.

Keeps the costs down. Perhaps more importantly, it ensures someone doesn't fit a J-130 spec part to a J-24x core, causing a failure.

J-24x is the target vehicle, J-130 is over-specified for it's task, but it performs well enough - no reason to spend lots of money optimising it.


However, there was talk of a block II core some time ago. Build the initial J-130 with a bit of extra margin, reducing design costs & development time. Get some flight experience, then build a core really optimised for the J-24x role - hopefully this would be lighter so gives better Lunar performance.

Later Saturn missions had higher performance than earlier ones, and shuttle's current ET is the "Super Light Weight Tank" exactly why you'd think.


Note, the baseball cards & all mission plans are based on the current ("block I") spec of the core. None of them assume lighter / higher performing vehicles.

cheers, Martin

[Idol Revolver]

Judging by Energia boosters, 4 Falcon-9 first stages would do just fine.  Also, they are already human-rated.

They are?  I didn't know that.  Rated to what standard?

COTS standard probably, since the falcon 9 was designed from the start to carry dragon.

[TrueBlueWitt]

Judging by Energia boosters, 4 Falcon-9 first stages would do just fine.  Also, they are already human-rated.

They are?  I didn't know that.  Rated to what standard?

COTS standard probably, since the falcon 9 was designed from the start to carry dragon.

http://www.spacex.com/press.php?page=20090729

First stage and interstage just completed qualification to "human rating saftey requirements" requirements for pressure loads.. and 1st stage also met those standards for Bending loads.

[Lancer525]

all the other associated engineering would have to be re-done from scratch, because all the plans, drawings, technical information and everything related to the engine was destroyed

That is a myth. Blueprints on the F-1 exist as the Saturn V engines were recognized to be the most valuable aspects of the vehicle for the future, as much as possible of their documentation was preserved.

Much more here: http://www.thespacereview.com/article/588/1

Interesting...

Much of what is available to the general public, in terms of historical documents and such, always repeats the myth you've just identified. Of course, the tooling, its design, and all the associated manufacturing necessities are still unavailable, and to re-start production of the F-1 would take funding that would better be spent on DIRECT.

Thanks for the link!

[Eerie]

You'd need to redesign the ET, since it only currently has two attachment points.

Or design something to hold two Falcon-9 stages together, attach a pair of them, and leave ET as it is. 

[clongton]

Lobo and phantomdj;
The Jupiter-130 core *IS* the Jupiter-24X core. We did not design the Jupiter-130, but actually designed the Jupiter-24X. All the Jupiter-130 really is, is an incomplete Jupiter-24X. It is missing the upper stage and the 4th SSME. It is not a separate launch vehicle per se; rather it is just a "flight configuration" of the Jupiter launch vehicle. It is not optimized in any way and therefore flies with less performance than it could have if it were optimized. But its performance anyway is more than "good enough" and the benefit is that there is no core difference between the 2 flight configurations of the 130 and the 24X.

[TrueBlueWitt]

You'd need to redesign the ET, since it only currently has two attachment points.

Or design something to hold two Falcon-9 stages together, attach a pair of them, and leave ET as it is. 

Falcon 9 Boosters might make some sense especially once(if) SpaceX developes their BFE(Big Falcon Engine)..