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The ideal design for OSP already exists; it was designed by McDonnell Douglas (now a part of Boeing) in 1967, and it was called "Big Gemini."
The Big Gemini was a lengthened Gemini capsule that could carry up to ten astronauts (if no cargo was carried.) It also had skids and a rogallo wing (which could be replaced today with the tested X-38 parafoil) so it could make runway landings. Best of all, the system was lightweight. As many folks have pointed out, OSP will cease to be either safe or economical if the heavy-lift variant of the EELV is used. But by keeping the mass low (i.e., Big Gemini or another capsule,) a single-core EELV can be used.
Like any solution, Big Gemini (or any capsule) has its drawbacks. In order to re-use a capsule, its thrusters and life support would need to be replaced between flights. Refurbishing the heat shield would also be difficult. The ablatve shield might be stripped off between flights (a la the X-15,) it could be given a thick ablative shield that was rated for a given number of re-uses (such as the re-flight of Gemini 2,) or tiles could be used. The tile solution would add many man-hours of time to inspect the shield, and adds a weight penalty. Look at how heavy Russia's re-usable Zarya capsule was, compared to Big Gemini. But because only a few capsules would be flown each year, it might make more sense just to build more instead of refurbishing them.
Ultimately, NASA will need a cheap, crew-only capsule and a true shuttle replacement that will haul big cargoes to and from the space station. Big G will fill the first niche nicely, and may even be used when mankind returns to the moon and ventures to Mars.
As to a shuttle replacement: the poor X-33 was doomed from the start because SSTO rockets are unforgiving when it comes to weight growth. Lock-Mart would have been better off if they stuck to the X-33's inspiration: Max Hunter's Starclipper. Although both ships were lifting bodies, the Starclipper and its successive designs carried most of their fuel in a cheap, expendable V-tank that fit around the nose of the vehicle like a collar.
It seems like OSP is getting less ambitious by the day as NASA strives to accelerate the time schedule while keeping the budget down. Although the vehicle will be fully autonomous (eliminating the need for pilots,) it will still carry only four astronauts to ISS. Novel maneuvering engines and better heat shields will probably be out of the question, as it will be cheaper and faster to use improved versions of shuttle-based systems.
If the images released by Boeing are any indication, a modern version of Apollo may be in the cards. I've read all of the pro-capsule and anti-capsule rants on spacedaily.com, and I tend to think that a lifting re-entry will be better for the de-conditioned crew, but a capsule might suffice when the obvious weight savings are factored in.
NASA essentially had a choice between building a cheap spacecraft that will fill a short-term need (replace the manned launch abilities of the shuttle ASAP) or building a more expensive but more durable OSP that could support larger crews aboard either the ISS or a larger, follow-on station. Although I can forsee the need both for a cheap capsule and a more luxurious space plane, it appears that NASA is choosing the former and not the latter.
Russian cooperation will be essential to near-term Mars exploration. NASA is going to the Russian Space Agency to buy RTG's for the 2009 Mars Smart Rover. Russia also has much more experience than the US for space nuclear reactors.
Visited by Moderator 2022/01/28
I'd assume that non-nuclear nations who have expertise that is useful to Orion should be allowed to participate. Having a competing nuclear-pulse program would defeat the entire purpose of the agreement. And as for countries like Pakistan or China holding out, I think that would breach (and thus nullify) the agreement. Essentially, the plan would require everybody to participate to be successful in ending proliferation. This will require a fundamental shift in thinking in Tehran and Pyongyang, and that's why I've relegated the idea to the "far-term" heap.
I've listened to the last few programs and enjoyed every minute. Keep up the thought-provoking discussions!
Guests I'd like to see:
Sen. Bill Nelson or Rep. Dave Weldon
Dr. Benton C. Clark of Lockheed Martin Astronautics
More people from Mars Society HQ
David Portree (of "Romance to Reality" fame)
Mark Wade (creator of Encyclopedia Astronautica)
Buran flew in space only once. Still, manned crews were always part of the Buran plan, in addition to cargo.
The reasoning with the shuttle was that it took humans to perform useful work in space like construction, retrieval, and repair. Even satellite deployment required humans, at least in the mind of the original shuttle planners. The idea isn't totally debunked, but separating crew and cargo is being pushed because it would result in a safer manned vehicle.
If the shuttle continues to fly through 2020, we can be guaranteed of losing another one, and possibly two, orbiters. If the shuttle is flown in a manned configuration for that long, it would be downright wrong to not provide the astronauts with an escape system. Such systems have been proposed in the past, but all have been rejected on weight/cost grounds.
Individual ejection capsules (on the B-58) have been tested at speeds up to Mach 2 and altitudes of 70,000 feet. This solution would also be light in weight and complexity. A crew ejection capsule, such as that on the X-2 or F-111, would be heavier, but it has been tested at Mach 3. Either would have given the Challenger crew a fighting chance at surviving.
For a Columbia-style accident, something better would be needed to withstand the plasma sheath surrounding the shuttle as it disintgrated. Engineers have looked at systems to survive these accidents. I feel that a spherical crew ejection capsule would be ideal, although it would be impossible to refit to the current orbiters. Maybe when NASA asks the industry to design a new-generation launch vehicle (not the diminutive OSP, which will have launch-abort rockets,) the spherical Voskhod-style capsule will be considered.
What are you, some kind of commie?
Hell no. I eat commies for breakfast.
International control over nuclear weapons is just an idea, not ready for near-term implementation, but an ideal to live up to nonetheless. Recall that the Nuclear Nonproliferation Treaty calls for the "eventual" eradication of nuclear weapons.
Under the current MAD setup, strategic weapons have no military value. There remain a few uses for nuclear weapons, but only ones with small yields. These include earth-penetrators and weapons designed to wipe out large troop formations (such a weapon must be beyond the capabilities of MOAB.) The existence of conventional weapons to do these jobs, and the high casualty threshold for using nuclear weapons, still make these weapons unlikely to be used. And as we've seen before, nukes are no deterrent against people who are too willing to "die for Allah."
The most useful thing we can do with our nuclear weapons is to use them for space propulsion and destroying asteroids. These issues affect the entire planet, and the entire planet's resources should be applied to confronting them.
I've thought about the air-launch idea for a two-stage spacecraft. It would require a Mach 4 staging speed and a fuel fraction of 65% in the orbiter. The problem with these ideas is always separation. It's much harder to separate two objects that are traveling at supersonic speeds instead of subsonic speeds. The airflow over a delta wing is supposed to be benign enough to allow staging, but a control failure on the parasite aircraft/spacecraft (such as what happened with the A-12 / D-21) will lead to the destruction of both vehicles. For that reason, bottom-carriage is preferred by most designers.
Of all the competitors, Burt Rutan probably has the best business plan. According to Space.com, it will only cost the operator $50,000 to fly each passenger on a fully-booked flight of SpaceShipOne. When companies are planning on selling tickets for twice that amount, the operators are certain to profit. Further, the White Knight and SpaceShipOne promise to offer faster turnarounds and reuse more of the airframe than the other competitors. Today's developments amount to a revolution in the field of private space travel.
This is truly exciting news. Can't say for certain that Burt will be the first to actually make it into space, though. Armadillo, Canadian Arrow, Star Chaser, and Da Vinci are all getting closer to making a flight attempt. It's great to have so many compaines striving to create routine space access. Utimately, everybody will benefit from the X-Prize.
Orion was feasible two generations ago and nothing has changed. If anything its more feasible in light of new technology. We could build one tomorrow morning if we wanted to.
After reading George Dyson's "Project Orion," I get the impression that the Orion group was still rather far away from getting definitive answers to their engineering problems. The most distressful was finding a method to compensate for a dud bomb. Others included the system to eject the bombs behind (through?) the plate and the shock absorber system.
That's not to say I think Orion is impossible; in fact, I think that it is our best bet for exploring the outer planets once enough time and money are invested in development. Thankfully, Andrews Space & Technology is doing research into magnetic pulse rockets that are quite similar, in design philosophy, to Orion.
Bill Sweetman has a pretty good article in Popular Science about the rise and fall of the Space Launch Initiative.
What we've seen from NASA over the past decade is a history of mismanagement, with X-33, X-34, X-38, and SLI being the prime examples. Sweetman focuses on NASA's stringient requirements for cost and safety on the shuttle.
NASA has said that it wants a factor of ten reduction in the cost of operating its new spacecraft. Yet it would still be agreeable if we could get a factor of four, or even a factor of two, when you're spending three billion annually on the current shuttle. Further, it is unreasonable to expect 10,000 launches without vehicle failure when the chances of failure in the previous vehicle were 1 in 56.5. It is more reasonable to design the spacecraft that gives the crew multiple means of escaping disaster--in both the ascent and descent stages. Crew survivability, not vehicle survivability, should be the deciding factor.
I also suspect that SLI was scaled back under pressure from Boeing and Lockheed Martin. When looking at their SLI designs, it was clear that they hadn't put in as much thought as Northrop-Grumman/OSC. And I suspect its because the SLI booster would be a direct competitor with their Delta IV and Atlas V, and if it were developed it would end their chances of recouping their original investment in the expendable rockets.
If NASA cleared the shuttle for commercial missions (no dice, unless the vehicle was privatized) or if the Air Force wanted to use the shuttle again, Vandenberg would make sense. Revenue-generating flights from Vandenberg would be the only viable reason to launch from there (because Titan IV and Delta IV heavy are cheaper replacements for the shuttle for the recon sat missions.)
The Enterprise Mission has now successfully found a new "face" at Baghdad (formerly "Saddam") International Airport and plenty of purported "parallels" between Iraqi architecture and the features on Cydonia.
After reading the article, I've officially heard everything. Pardon the pun, but these new claims are some really funny Shiite.
Even if NASA achieved the desired monthly launch rate, a shuttle launch would still cost over $250 million. Opening a second launch site at Vandenberg would further increase that flight rate, but at greater fixed cost to the taxpayers. Clearly, we need something beyond the shuttle with greater reusablility and an airline-type business model. The ship should be turned around quickly and kept flying for as long as possible. The shuttle fails in this aspect, and Buran would not have been a drastic improvement.
Energia could have been used for some grand purposes, but there were other ideas the Soviets had for it that were either scary or nonsensical. The first Energia launch was supposed to orbit Polyus, a space weapon system. Other "wise" proposed uses for Energia were:
--Replenishing the earth's ozone (even though most of the ozone is found in the troposphere)
--Illuminating polar cities
--Chucking nuclear waste into the sun
Essentially, the Soviets were trying to invent near-term uses for Energia even though very few really existed. If somebody commited to lunar/Martian exploration and required a high flight rate, a rocket like Energia could be financially justified.
I'll say. This should have been moved to a different area of the forum long ago. But I can say with certainty (thanks, in part, to this thread,) that the war was the most polarizing issue of my generation. Let's end this now and talk space again!
--Warning: Thread may become potential flame!--
Could Buran have been an economical space vehicle, learning from the mistakes of the shuttle? To be fair, Buran had a number of improvements over the shuttle. Liquid fuel boosters, ejection seats, LOX/kerosene OMS, and a drag chute (later added to the shuttle) would be just a few. But the Buran heat shield would presumably be vulnerable to debris, in the same way the shuttle was. And would replacing the four Energia engines be cheaper than refurbishing the shuttle orbiter's three engines?
My belief right now is that Buran would not have been cheaper because of a low light rate. This is the same reason why the shuttle is not economical. And I think this low flight rate is due to the low demand for the shuttle's services. If Buran went operational, it would have been used to service Mir and Mir 2, and I don't think that these projects could have justified Buran (although the Energia booster's costs would be reduced by the grandiose plans the Soviets had for it.) If anybody has some cost figures, they would certaily help the debate.
If the Pentagon has it's way, Iraq will be governed by Iraqi expatriates. The CIA and State Department were pushing for American interim government. I think we'll see a compromise between both positions, but I'd expect the Iraqi expatriates to be more independent and more popular with Iraqis. The UN will play a role, particularly in meeting the humanitarian needs of Iraqis, but that role must be determined by the divided security council.
The war is not yet over. Several objectives remain.
1.) The coalition must defeat the Special Republican Guard and other Hussein loyalists in Tikrit.
2.) The prisoners of war taken by Iraq, both in Gulf War II and the unreleased prisoners from Gulf War I and the Iran-Iraq war, must be set free.
3.) WMD must be thoroughly investigated. We haven't heard much about this because the Pentagon does not want to announce a possible WMD site only to have the evidence refuted (as the news channels already have.) There are several sites "of interest." National Public Radio had previously announced the discovery of missiles that contained nerve agent, and while it is easy to call this the "smoking gun," all of these suspect sites must be investigated. The untold story of the war has been the work by special forces to destroy Iraq's banned missiles. I believe that when all has been told, Iraqs possession of al-Hussein (SCUD) missiles, and probably weapons loaded with chemical agents, will be exposed.
4.) al Qaeda must be purged from Iraq. Perhaps you have heard about the terror camp at Salman Pak. Marines recently raided it. When they did, they found foreign fighters and an old airliner that, according to defectors, was used for hijack training. In my estimation, Iraqi sponsorship of conventional terrorism was more dangerous to the United States than their WMD. When this is all over we may finally be able to answer whether Iraqis trained the Saudi and Egyptian nationals who would eventually attack the United States.
Rebuilding Iraq may take up to two years. But when it is done, the United States will be able to withdraw from the Saudi bases that supported the no-fly zones. Essentially, the success of achieving our political objectives (the Clauswitzian reason for going to war) hinges on our handling of the rebuilding. If the post-WWII rebuilding is used as a model, and a greater committment is made to the Israeli-Palestinaian peace progress, stability will be restored to Iraq and it may hopefully spread to Palestine, Iran, and Syria. This, in turn, will allow us to save money that would be spent on further "police actions" in the out years.
So when that $74 billion is recouped, I'd spend it on space, scientific research, some conservation projects, and paying down the debt.
Sure, you could buy the homeless a trailer and give them a chunk of money, but would that solve their problems? The gift of money would not necessarily motivate these people to work or rehabilitate themselves. Many of them are addicted to substances or mentally ill. They need the intervention of friends and family, and they need a hand up, not a hand out.
Middle class tax burden? The wealthiest ten percent bear 96% of the tax burden in the United States.
$74 billion is a lot of money, but can you put a price on our security, or the freedom of Iraqis? If our freedoms were gone and we lived in fear of government, would we be putting a price on our liberation? This money will come out of the Bush tax cut, which supposedly benefits "the wealthiest one percent."
The idea of ejecting an RLV from a cargo aircraft or launching from on top a large subsonic aircraft is not new. I just haven't heard Buzz Aldrin promoting it. To date, Buzz has been talking about vertical takeoff vehicles with reusable "Starbooster" flyback boosters.
Project Orion gives the world an opportunity to disarm itself of nuclear weapons in a multilateral way. I've thought of an "Orion Peace Initiative" that works like so:
1. All nuclear nations, including North Korea and, within a few years, Iran, must declare their full nuclear stockpiles.
2. Based on the capacity of each naton's stockpile, a proportional number of astronauts from each country will be chosen for journeys to Jupiter and Saturn.
3. The nuclear nations will design the Orion Spacecraft (plural) that will be employed for testing and eventual flights to the outer solar system.
4. The nations will retain their stockpiles, but these stockpiles will be re-manufactured into Orion pulse units under IAEA supervision. A small number of warheads will be retained by the IAEA to deter against additional nations developing nuclear weapons (this idea is a direct descendant of Henry Stimson's idea to put nuclear weapons under international control.)
I see a few problems with this idea. For instance, what if some countries make like Iraq and don't declare their entire arsenals? And how do we get nations like North Korea and Iran to comply if they have no interest in the peaceful uses of nuclear weapons? The plan is incredibly idealistic, but I believe that it deserves a chance.
Angara will likely launch from Plesetsk. I'm most excited about the winged, recoverable variant of Angara, granted the Russians find the money to build and test it.
I think Bristol's design philosophy is sound, but I think their performance estimates are optimistic. The Ascender will be hampered by the jets and the runway takeoff (bigger wings + jets = higher weight + lower performance.) Hydrogen fuel is also a negative because much of it will boil off while the Ascender is under jet power (look at the figures for oxidizer boil-off during the X-15's flight to release altitude; you'll see what I mean.) The Spacecab and Spacebus follow-ons are a bit optimistic about the speeds they will achieve using turbojet engines.
Starchaser is following a conservative design philosphy that will make them a contender for the X-Prize (they've already finished most of their testing,) but it's commercial prospects will probably be limited. I just don't think that people will enjoy being squashed in a capsule for their brief spaceflight.