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I'm not going to debate you anymore publiusr since you are refusing to listen to me.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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Frankly--we haven't seen that Delta IV can put 20 tons in LEO yet.
Nonsense. The dummy payload did achieve orbit, just that it was highly elliptical (about 10,000 mi too low at perigee.) I admit that this argument is open to nit-picking (the dummy sat wasn't 20 MT, the orbit wasn't a "low" earth orbit, etc.) The point is that Delta IV Heavy is a capable replacement for the Titan IV, and a fix for the cavitation problem will probably be minor.
When the next DSP is launched, Delta IV Heavy will be vindicated. We can only hope that an Atlas V Heavy is in the works.
Who needs Michael Griffin when you can have Peter Griffin? Catch "Family Guy" Sunday nights on FOX.
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Do we want lunar exploration to be sustainable? If so, the elements of the moon ship should be sized for flight on an RLV. This scenario actually favors the four-launch method of going to the moon and back.
It will be a while before an RLV is developed, unless private industry tosses a lot of funding and effort at the problem. But judging by past studies, an RLV will carry a payload in the 20-25 MT range. According to David Urie in "The Space Review," the original purpose of VentureStar was to replace the Titan IV (not the shuttle.)
Even Robert Zubrin examined the possibility of doing a Mars mission using RLV's. It envisioned 40 or more launches to loft the spacecraft elements and the fuel. Yes, it's impractical. Yet at this stage in our technolgical development, it's not possible to build a heavy-lift RLV. Maybe we could have reusable boosters on an ELV, but not a true heavy-lift RLV.
Roll back the clock to 1996 and see that Zubrin also proposed a six-launch mission called Athena that would fly by Mars and allow humans to operate Mars rovers in real time. There was a time in the past when Zubrin was a realist.
My point is that, while HLLV is the quickest and easiest way of getting back to the moon, an EELV-based mission has more potental to be sustained over the long term. If an RLV comes along, it could launch the CEV and EDS in two launches. Lunar oxygen would enable a reusable lander, although another two RLV launches would be needed for periodic deliveries of hydrogen to the moon.
Who needs Michael Griffin when you can have Peter Griffin? Catch "Family Guy" Sunday nights on FOX.
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Excelent point,
In order to transition from an expendable system of moving crew & cargo to/from the Moon, both types of systems should be sized for payloads that are no larger then what an RLV can carry.
Lucky for us, the EELV+ scheme is appropriatly sized
Building a heavy-lift RLV isn't going to happen without a revolutionary propulsion or materials breakthrough (SWCNT composits, liquid N5+ cation fuel, etc).
Why not? Because building and flying a mega-huge RLV is harder then building and flying a smaller one more often for an equvilient payload.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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The smaller the RLV payload, the more economic sense it makes. That's why the RLV startups got so excited about Iridium, because it would put up a constellation of many small satellites. The launch frequency determines whether a launch vehicle should be expendable, partially-reusable, or fully reusable.
The original DC-X business model was a work of genius. SDIO needed to put thousands of tiny "Brilliant Pebbles" interceptors in space, so they wanted McDonnell Douglas to build them a vehicle that would launch an interceptor, return to earth, and be ready to fly again within days instead of months.
If our industry is bold enough, they will catch on. They will build a 25 MT RLV, make it able to turn around in two weeks or less, and make the moon cheap and accessable.
Who needs Michael Griffin when you can have Peter Griffin? Catch "Family Guy" Sunday nights on FOX.
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The smaller the RLV payload, the more economic sense it makes. That's why the RLV startups got so excited about Iridium, because it would put up a constellation of many small satellites. The launch frequency determines whether a launch vehicle should be expendable, partially-reusable, or fully reusable.
The original DC-X business model was a work of genius. SDIO needed to put thousands of tiny "Brilliant Pebbles" interceptors in space, so they wanted McDonnell Douglas to build them a vehicle that would launch an interceptor, return to earth, and be ready to fly again within days instead of months.
If our industry is bold enough, they will catch on. They will build a 25 MT RLV, make it able to turn around in two weeks or less, and make the moon cheap and accessable.
Well, I wouldn't say smaller is always better, but for a reasonably sized vehicle with todays' technology, a payload around 20-25MT sounds about right for an airliner sized vehicle that would be optimal.
The old DC-X was a doable ideal, though I don't know if it could be flown daily it could be flown weekly probobly, the trouble was it didn't have quite enough payload. It only carried around 10MT and it was bigger then the Shuttle main tank. The use of more advacned technology, like slushed hydrogen and aerospike rocket nozzles might make up for it though.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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I'm not going to debate you anymore publiusr since you are refusing to listen to me.
That suits me just fine, mister--since you obviously haven't been listening to our Chief Admin-to-be, who I share my opinion with.
My point is that, while EELV is the quickest and easiest... an HLLV-based mission has more potental to be sustained over the long term. 500 tons in five flights, verses 100 tons in five Delta IVs--assuming they get it straight.
Nice article from Mr. Bell. He called this one right for a change:
http://www.spacedaily.com/news/oped-05z … -05zi.html
"This Delta-4H fiasco was impossible to explain away easily. It occurred right in plain sight of too many people. At ignition there was a huge hydrogen fireball that enveloped the whole vehicle. The lower stages were actually burnt black. Then those same damaged stages shut down early. The two amateur recon satellites built by the Young Spies fell into the atmosphere and burned up. The main satellite went into a useless orbit in full view of Eurasian and Eastasian tracking stations."
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Now see, there you go again... "100MT in five flights" stuff. Last I checked, 27.5 didn't equal 20.0
Jeff Bell is well known as a loud mouth who hates everything that isn't astronomy-centric and says things that are half or completly untrue often.
We've been over this before:
-The fireball is natural, a consequence of the fuel-first engine startup. Its supposed to do that.
-The fireball doesn't really hurt the metal vehicle, the insulation is trivial. You don't need it during acent.
-The stages were not damaged by the fireball and worked flawlessly except for a fuel sensor arrangement.
-The CBCs are basically identical to the Delta-IV Medium, which have all flown flawlessly. If they work, so does the HLV model.
-The satelite was a dummy payload, mostly full of brass rods and a radio beacon.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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Assuming the 27 ton estimate is accurate--more like 20-22. That remains to be seen. Delta IV is an unproven bird at best, and it is not best for long term Mars exploration. SDV HLLV's save a step, and allow more robust moon missions to the lunar poles. Two HLLVs and Lunar/Earth Orbit Rendevous would allow easy access to the polar regions.
Delta IV would require a lot more docking refueling nonsense and gives you all kinds of problems.
Jeff Bell has his points--warts and all.
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Not really, and infact a direct-return arcitecture would severely penalize your Lunar payload versus Delta-IV EOR.
Docking events simply aren't that scarry, they are relativly easy. There would be no refueling, just one docking event in LEO to mate with the seperatly launched TLI stage.
Nope, Jeff Bell is an idiot who wants people to hate NASA no matter what they do, and fall into some kind of Astronomy-worship as the sole noble use for space program money.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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It's important to note that Jeff Bel''s background is indeed in space sciences and astronomy, not in any branch of engineering. The frequent theme in his screeds is that manned spaceflight is too hard, so let's just not do it anymore. It's a very provocative position, but it's not too far away from that of The Planetary Society (robots yes, humans no.) Jeff Bell makes just enough insightful points to win people's attention (especially with his criticism of the OSP when that program was dying down,) but he takes too many logical leaps of faith that are untenable.
Who needs Michael Griffin when you can have Peter Griffin? Catch "Family Guy" Sunday nights on FOX.
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That is a fair critique of most of his sayings. We wouldn't even have a space race were it not for Korolov exploiting Stalin's need to have to bomb now rather than waiting to shrink the warheads.
The R-7 was the HLLV of its time--and people also bashed it. It was a true space booster sold as an ICBM--rather than the other way around.
The one thing Bell needs to understand is that the larger human-rated launch vehicles made automated probes happen. They still make that Vostok capsule as a materials research sat--and as a spysat too in the past.
Had our first ICBM been Minuteman--and the first Russian ICBM been Topol-M--we wouldn't have spaceflight of any real kind. Thankfully the big liquids came first--which saved our behinds.
If Bell thinks a good Europa lander can be launched by that crutch of a Delta II, he is out of his mind. I want an HLLV to put a good Solar foci scope 500-800 AU out to get some really good extr-solar planet pictures. HLLV's are best for that.
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Please show the math. . .
= = =
PS - - Both the Aldridge Commission and the Planetary Society concluded the VSE needs heavy lift. If they are wrong, explain how they made that error.
= = =
PPS - - Neither commission can be accused (IMHO) of being Zubrin-loving kool aid drinkers. :;):
Edited By BWhite on 1111260812
http://www.universetoday.com/am/publish … tml?412006
The centerpiece of NASA's Vision for Space Exploration is the new spacecraft that will carry astronauts to the moon, Mars and beyond. Jeff Hanley, appointed as Constellation Program manager in October, discusses the development of the new Crew Exploration Vehicle, the role of the International Space Station, and the path of the 'Vision
'first steps are not for cheap, think about it...
did China build a great Wall in a day ?' ( Y L R newmars forum member )
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The Space Review had another hit piece on HLLV which I will not dignify with so much as a link.
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Even so--chew upon this.
If missile defense money goes into useless ground-based silos that Republicans dig and Dems bury over with Caterpillers--it helps us not a jot. If the money for SDI goes to an HLLV--then if a Dem gets in office--we still have a good booster out of the deal--instead of moth-balled silos that help space-exploration and solar powersat construction not at all.
In this sense ONCE HLLV IS UNDER CONTRACT, it becomes politician-proof. It keeps the shuttle jobs in place, and institutional inertia keeps it flying as it has kept the shuttle. The only diff' is that the SDV puts up 100 tons of cargo--not a puny 20 ton load with a big orbiter people are after with a hatchet.
Both Dems and Reps should support this--in that--if a Dem gets in office--it won't be as if that HLLV money has been wasted, because it--unlike JSF and other SDI tech--has a use beyond the military. Space Based Solar Power sats are best built with HLLVs.
My goal is to ramp up throw-weight to get us out of this
THALL SHALT NOT LAUNCH OVER 20 TONS TO LEO mindset the bean counters have locked us into.SDV is only the beginning. I will not rest until SDV HLLVs are the smallest boosters we have, with that crutch of a Delta II banned and Sea Dragon flying with 550 tons to LEO. Only then will space open up to commerce--in bulk--not in Rutan's useless toys.
My mantra is that we all should be in the one true Church of the Heavy Lift.
Thy five segment solids comfort me--and the EELV heretics shall be put to the sword :angry:
Energia Heavy Lift Launch Vehicle
http://www.k26.com/buran/
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Yeah, I saw that. HLLVs have been getting more popular over time with some at least.
http://www.directlauncher.com/
http://www.launchcomplexmodels.com/Direct/
http://www.hays.cc/direct/DIRECT_Launch … v1.0.4.pdf
http://www.directlauncher.com/doc/DIREC … v1.0.4.pdf
http://simcosmos.planetaclix.pt/temp/Di … v1.0.4.pdf
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Yeah, I saw that. HLLVs have been getting more popular over time with some at least.
http://www.directlauncher.com/
http://www.launchcomplexmodels.com/Direct/
http://www.hays.cc/direct/DIRECT_Launch … v1.0.4.pdf
http://www.directlauncher.com/doc/DIREC … v1.0.4.pdf
http://simcosmos.planetaclix.pt/temp/Di … v1.0.4.pdf
thanks for those links
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Heavy Lift is gaining followers.
Discovery and the Science Channel Will have new shows based on VSE and will show pictures of Ares V, which has grown of late:
http://www.nasaspaceflight.com/content/?cid=5086
http://starshipmodeler.net/cgi-bin/phpB … hp?t=47784
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French ESA Ariane-6
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