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Well, my impression is this: Something crashed at Roswell that was not a weather balloon, and the government was and remains keen on keeping a lid on it. But that hardly means it was an alien spacecraft.
I tend to agree with this sentiment. Very credible people have described the wreckage, while most of the witnesses to alien bodies have been dismissed as cranks or have tried to sell their stories.
As Columbia and high-speed jets have proven, the debris field of a high-speed, high-altitude aircraft is very long. The Roswell debris field was quite small, about the size of three football fields. Whatever exploded there must have been small and going low and slow.
The nature of the wreckage suggests that the craft's structure was very high-tech, but not alien by any stretch. I-beams? Fibre-optic cables? Memory alloys? The Roswell wreckage matches these now-common items.
Anybody who wants to learn the full Roswell story should read from Phillip Klass (anti-alien) and two very different, pro-alien accounts (but still very thoroughly-researched) from Stanton Friedman and Kevin Randle.
Botom line is that I think it was probably a secret aircraft project. The Germans had a number of saucer-shaped aircraft in development by the end of WWII, and it's not impossible that one was captured and tested in the US. Why a secret aircraft would stay that way over fifty years ater is beyond me, but many of the government's secrecy rules are quite arcane. Anybody who has tried to get info about spy satellites knows what I'm talking about.
It looks like NASA has chosen an architecture for the lunar return, or at least placed a restrictive condition on what kind of input the contractors will have in designing the architecture.
NASA is committing to at least two flights per mission by dictating a docking between the CEV and the Earth Departure Stage. This rules out Orbital Sciences' plan to launch everything at once on a Magnum-like rocket.
That's not to say that the VSE can't be saved. An 80 MT launcher (like Shuttle C) can put up the EDS and the Lunar Surface Access Vehicle, while a Deta IV / Atlas V Heavy would launch the CEV and its service module. That lowers the bar, so the engineers won't have to re-do Apollo with a Saturn V megabooster.
Speaking of lowering the bar, how about the minimum requirement for four astronauts? You would think that six would be the minimum, especially if Mars is the ultimate goal of VSE.
Robert Zubrin's Mars Direct calls for the http://www.marssociety.org/images/direc … .gif]Earth Return Vehicle to launch from Mars surface directly to Earth.
Maybe somebody can help me understand the numbers on this drawing. Initially, it says the dry masses of stages 1 and 2 are 6.33 and 1.77 tonnes, but later it says that the inert masses for stage 1 and 2 are 8.85 and 2.56 tonnes. Aren't these terms descibing the same thing? Is something extra included in the inert mass that isn't in the dry mass?
(BTW, his mass fractions for the stages are a bit optimistic but still in the acceptable range.)
The study recommends reviving Energia, but doesn't necessarily commit ESA to doing so. It would probbly be the cheapest option for ESA, though.
My problem with the study is that it rules out technologies that would dramatically improve our odds for successfully making it to Mars and back. Nuclear power, NTRs, ion engines, and in-situ propellant production are all off the table. Aurora is quickly becoming a re-hash of Battlestar Galactica.
The drawings show a lot of future growth potential. Looks like the launch abort tower will be replaced with a skirt of abort rockets that are positioned behind the capsule. Also, pic 24 shows an alternate aeroshell with wings on it.
You can also see a Buran in the background. I wonder whether it's a mockup, the jet-powered aerodynamic test model, or an unfinished orbiter.
I think that the launch market will not be so kind to Musk & co. to allow them three launch attempts. I feel that Falcon I will be sunk if it fails on its first flight, because Musk has spent so much on unconventional designs to squeeze performance out of his rocket.
Even for an industry giant like Boeing, two consecutive failures were enough to sink the Delta III. Even a successful test flight after the failures could not woo any potential buyers. The only silver lining here is that the new SRB's for Delta III were put on the Delta II, while the Delta III upper stage was used on the Delta IV.
Falcon V is now expected to deliver 6.02 tonnes to a 200 km orbit and 5.45 tonnes to a 400 km ISS orbit. The payload to a 400 km orbit at 28.5 degrees should fall somewhere in between, owing to the earth's extra rotation at the lower longitudes of Cape Canaveral versus ISS. By contrast, Soyuz weighs 7.22 tonnes and flies to an ISS orbit. Unless somebody can radically reduce the weight of the spacecraft, it's looking less likely that Falcon V will be used for either the Bigelow Prize or the proposed Rohrabacher prize.
Of course, the Falcon pad is at Vandenberg, so it looks like there will be only polar launches until something is built at Canaveral.
One of the elementary principles of economics is scarcity. If a material is scarce, it is bound to be more expensive. Lithium is scarce, and it costs much more than standard aluminum.
I don't know what it would cost to produce both the standard and lightweight tanks concurrently. Floorspace and money could be saved if the plant alternated between production runs of Al and Al-Li tanks instead of building both at the same time. I tend to think that this setup could still be justified in the face of Al-Li's higher cost. Really, I think the Al-Li tankage should only be used for the manned version of Delta IV. That way, the weight savings could eliminate the need for the failure-prone solid rockets, and you could possibly get away with launching the CEV capsule on a single-core booster.
Again, my concern would be the vertical stabilizer of the aircraft. To launch the MAKS, the MAKS would have to be released at a significant nose-up attitude, and the mothership would have to make a steep, diving turn after releasing the MAKS.
Al-Li tanks are inexpensive to develop and would increase the capacity of the Delta IV, but they should only be used for missions where the extra lift is needed. Al-Li is much more expensive than Al; hence the reason why it wasn't used in the first place (Delta IV is about as close as we will get to a "big dumb booster.") Both cores should remain in production.
I wonder how far SpaceDev can take the Dreamchaser space tourism vehicle. They claim it will be better than SpaceShipOne, but they're also doing the SS1 engine. Hedging their bets, I see...
It would be interesting to see if you could launch MAKS from an Airbus A380. There's still the problem of clearing the single, tall tail. At least it can carry a heavier payload than the 747.
Our favorite curmudgeon is back!
It had been a while since Jeff Bell has written for SpaceDaily. He comes back with a few witty lines, such as calling the Nuclear Regulatory Committee "Girly Men."
I did find it interesting that Rohrabacher wants to create a $100 million prize for a 3-man capsule while Bigelow is putting up $50 mil for a 5-man capsule. Obviously, the government's pockets are much deeper than Mr. Bigelow's.
One point I wanted to make is that Rep. Rohrabacher wants this prize so he can stimulate the private space sector, although his proposed mission requirement is highly arbitary. I would prefer a more purposeful mission for this prize: carry a crew of six, and make the capsule able to spend 450 days in orbit if needed. That's your CEV in a nutshell. It's a more demanding requirement than the three-person capsule, so it would be appropriate to offer a bigger prize. But I still believe that a prize system for CEV would result in getting a quality product faster than under traditional contracting methods.
I'm sorry to steer this thread in a totally different direction, but it is a thread for CEV information...
As some of you may know, Rep. Dana Rohrabacher is fighting for a $100 million prize for a private, three-man spacecraft that can complete three orbits of the earth. When I see an elected official making such a bold call for an outlandishly large space prize, I have to say, "Why not set up the CEV as a cash prize contest?"
Let NASA write the mission requirements, while the private sector will have unlimited freedom to meet those requirements in whatever way they choose. NASA will offer a large cash prize, plus a guaranteed purchase of multiple CEV's for ISS and lunar missions.
It's quite a leap beyond the X-Prize, but its the kind of prize we need before we can aim for the ultimate goal: the Zubrin-Gingrich Mars Prize.
comstar, what you're saying is all well and good, but it doesn't get us any farther towards our common goal of routine spaceflight.
Air-launch concepts like SS1 are good for suborbital space tourism, but orbital flight is an entirely different animal that is far more demanding. Until somebody can develop operational scramjets, air launch will not be a viable launch system for anything except throwaway rockets like the Pegasus.
Vertical takeoff rockets may be old-hat, but that's because they have a proven record of success. It's the way space vehicles will be built until somebody comes up with some incredibly lightweight materials for structure and thermal protection (unobtanium,) or high-performance engines are devised.
Even if you do fly it piggyback, it is unlikly a vehicle with a large crew would fit on top of a 747, and one with any kind of payload definatly wouldn't.
Even a tiny spaceplane like MAKS needs the AN-225, the world's largest aircraft, to launch it. Larger spaceplanes would need gargantuan motherships.
The problem with air-launch schemes (in layman's terms) is that the mothership only contributes about Mach 0.8 to the Mach 25 needed to achieve orbit. If you could build a faster mothership it might solve the problem, but the staging altitude must be very high to avoid separation problems.
Winged rockets have lower "gravity losses" than conventional rockets, but the wings come at the price of higher drag and weight.
I'll agree that it's really pushing the limits of what can be done with a Falcon V booster. My hope is that advances in lightweight materials will help to bring the Soyuz replacement within the weight range of the original Soyuz. Maybe it can't be done, but it deserves study. If it can't be done, a booster with a 14 tonne payload will have to be brought in, and a Kliper-style spacecraft will be needed to service Bigelow's hotel.
Based on all of Bigelow's interviews, he's really asking for a Soyuz stand-in. Assuming that the contest allows for an expendable booster, Bigelow wants a spacecraft in the 7,220 kg range. If the new spacecraft could be held to Soyuz TMA-range weights, the Falcon V will suffice.
Of course, the 80% reusability dictates that more components from the retro module should migrate inside the reentry capsule. You also need to fit in two more passengers, but the orbital module becomes redundant and can probably be discarded.
What Bigelow will end up with is a larger Soyuz with greater reusability at the expense of greater weight.
If you want detailed plans, they are usually tucked away in company archives. I was reading a story about Boeing and Northrop-Grumman going into the old Grumman archives to get plans for the lunar module. Among companies, they have different policies about granting access to their archives. The old Grumman used to be very open about its archives; things changed drastically after Northrop bought the company.
Non-Americans can still win Bigelow's prize, as long as they move to the US and use the country as their primary place of business. Further, Bigelow is offering up to $1 bil in contracts to fly to his space station to the winner of the prize. Orbital flight may cost more than $50 million, but Bigelow's supplemental contracts will offset that. Is NASA offering supplemental contracts for the proposed orbital prize?
The major sticking point here is 80% reusablility. The Bigelow prize is ambiguous about thether that's for spacecraft + booster or just the craft. If it's the latter, I would think the prize was realistic. The former is unworkable on a five-year time frame.
I wonder if the HL-20 fares much better than the X-38 in terms of landing speed and impact forces. The HL-20's advantage was its lower wing loading (if the craft could be counted as a wing.) As heavy as the parafoil is, t might be needed on the HL-20 to slow the thing down to an acceptable landing speed. If the benefits of parafoil-assisted landing for the HL-20 are negligible, it would be better to equip it with standard circular parachutes in case the vehicle aborts a launch over water.
I also suppose that in the X-38 lift body design, that low-speed control wasn't a problem, since it wasn't going to come back down to a runway... just plunk down with parachutes on White Sands or somthing.
Give this http://mae.ucdavis.edu/faculty/sarigul/ … .pdf]paper a look. There's a lot of good info in here, but some of it has direct implications for lifting bodies. I found a particularly good quote on the subject of the X-38 (the lessons from which could apply to some degree to all lifting bodies):
Its average durng the last four test drops, which were considered by the test team to be very good, was 15 ft/s vertical with an average impact acceleration of 12 g's... As a comparison, naval aircraft hit an aircraft carrier flight deck at 10 ft/s. The X-38 landing gear was damaged or destroyed often during its test landings.
Keep in mind the advantages of having both the CEV and Kliper in production at one time. You could have them compete on a per-launch basis to get a better price, and there's more redundancy should one vehicle be grounded.
I'm not too worried about "no single corporate entity being able to pull it off." No single company is being asked to execute the full Vision for Space Exploration. Bear in mind that each of the Saturn V's three stages was built by a different prime contractor. The Apollo CM and LM were built by different contractors. When we finally get back to the moon, it will be a national effort.
Robert,
I agree that a MAKS type spaceplane is long overdue. But the HL 20 cannot and should not be adapted to this mission. It lacks the pitch authority and low speed handling characteristics to perform the mission. Many papers have been written criticizing lifting bodies for their low speed handling. This is why Max Faget rejected Max Hunter's Starclipper. It's also why the last concepts we saw from Orbital Sciences' OSP depicted an HL 20 with true delta wings.
The shuttle is a great white bird like an albatross that hangs around our necks, like the burden described by Samuel Taylor Coleridge.
If we could find a way to reduce the number of shuttle flights from 28 to 22, it would relieve schedule pressures (only 4 flights per year to retire by the end of 2010,) or it could result in early retirement if a safe program of five flights/year was achieved.
Most surprisingly is the way tht Boeing and NorthGrum will switch roles as Project Constellation transitions from Spiral 1 to Spiral 2. Does Boeing trust NorthGrum enough to take their word on it that the switch will happen? The changing business climate may force the companies to rethink their alliance at some point down the line.
![http://www.marssociety.org/images/direc … .gif]Earth](http://www.marssociety.org/images/direct/marsd6.gif]Earth){kind=link}