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Lockheed Martin unveils Space Shuttle replacement
Vegan Bob writes "Lockheed Martin released its proposal for the Crew Exploration Vehicle (CEV) in a recent Popular Mechanics article. NASA will choose this vehicle scematic or opt for the yet-released Northrop Grumman design in 2008. The CEV will replace the Space Shuttle program, and will eventually go to the moon (between 2015 and 2020)."
This is a lifting body, it does NOT have wings like the shuttle's. Where the "wings" are on the LM CEV,LOX/Fuel Cells/and other avionics equipment is stored there.
Also, this is NOT the CEV that is going to be going to Mars. The Mars mission isn't until past 2020 and when that happens, the CEV will have been updated quite a bit.
So now, lets have a Capsule vs Lifting body debate!
No. Carbon-carbon is not ceramic. And backed-up doesn't mean that it's a double layer.
Carbon-carbon is the material that forms the leading edge of the wings, which failed from impact damage on Columbia. By backed-up I presume they mean that the material will be structurally supported underneath, probably by a continuous backing layer. The leading edge of the space shuttle wings were not structurally supported underneath. The interior of the carbon-carbon pieces on the shuttle wings is hollow.
Fascism trolls keeping me up every night. When I starts a preachin', he HITS ME WITH HIS REICH!
That's because shipping cargo on the Space Shuttle was a dumb idea. Humans have very special needs (e.g. safety, atmosphere, low G tolerance, etc.) that cargo doesn't usually have. As a result, it's usually more cost effective to split manned missions and cargo missions into two seperate craft.
With that in mind, we've already got the cargo craft in the form of the Delta, Atlas, and Titan rockets. Now all we need is a human capable craft that doesn't haul 80 metric tons of (mostly) useless material into orbit.
Javascript + Nintendo DSi = DSiCade
Thats the whole point, the cargo is sent up seperately, maybe in a mission pod designed to be a cargo launcher. This way, if anything goes wrong, you jetison the CEV and leave the cargo to be destroyed. On missions that dont have heavy payloads like satillites, you arent carrying all that weight of a largely empty cargo bay up. The shuttle couldnt really be reconfigured to save weight, the CEV will be.
Further, NASA was a part of the United States Air Force at the time, not a separate entity with its own (very limited ) budget.
Erm, what?!?
NASA has always been a separate, civilian agency. It grew out of the old National Advisory Committee for Aeronautics (NACA), itself a civilian organization.
The Air Force did have its own space program during the late 1950s and early 1960s (around the same time as the creation of NASA), which centered around the X-20 Dyna-Soar and the Manned Orbiting Laboratory. The USAF even built an astronaut school at Edwards Air Force Base, and Chuck Yeager was the commandant. However, that whole program lost steam in the mid 1960s and was abandoned by 1969. This led the USAF to send its best remaining astronaut pilots to NASA, and convert the school into a test pilot school.
Even so, many of the most famous astronauts from the Apollo days were not USAF pilots. Neil Armstrong was a civilian (he worked for NACA in the X-15 program), and Buzz Aldrin, Jim Lovell and Alan Shepard were US Navy pilots.
The difference between then and now, in terms of budgets is this: First, the entire nation was deathly afraid of the Red Menace and national pride was on the line (nobody wanted go to sleep by the light of a Commie moon); Second, a very charismatic US President had staked his legacy on the US getting to the moon before the end of the 1960s (this at a time when the US had only put one man in space, and briefly, at that) before being assassinated and leaving the entire nation in shock.
Congress voted big dollars to the space program because it helped fight the blasted Commies, and because Lyndon Johnson, among others, helped spread the pork to important states (California, Texas, Missouri, New York, Florida, etc.). It also helped the nation pay its final respects to JFK. By the early 1970s, however, Americans began to question the investment in the space program, regularly saying things such as, "I don't think it makes sense to spend so much money to send people to the moon when we have so many problems here on Earth that we need to deal with first, such as hunger, pollution, disease, poverty, etc."
You made some valid points in the rest of your piece, but your glaring fallacy about NASA's status kind of undermines your credibility, don'tcha think?
Thats some really expensive material.
.5% of the mass of the Earth is titanium. The high cost is due to the chemically intensive refining process. Due to incremental improvements titanium prices are relatively low and stable. Titanium has only been available in commercial quantity for about 60 years. Our ability to produce it has improved rapidly.
The element itself is rather common; over
As such, it is no longer thought of as an exotic SR-71 class material by engineers. The A380 is 9% titanium by weight; that's just under 30 short tons of titanium per aircraft.
New processes are being developed that should help drive the cost of processing ores down substantially. There also happens to be large titanium content in moon rocks.
Lurking at the bottom of the gravity well, getting old
If you read TFA, you have a wild imagination to see some of the things in there that you claimed were in there. But to answer your questions specifically:
Why add an orbital rendezvous requirement to all missions?
We don't use the Shuttle for all missions, and the Russians don't use Soyuz for all missions. If we don't need humans or a rendezvou, we use Delta and Atlas rockets. You build to the mission, and this is built to the mission.
Why use a shape like this which, I presume, requires the use of failure-prone ceramic tiles for reentry protection
It says no such thing. In fact, from a reentry standpoint, this craft looks like what the shuttle was *supposed* to be, but wasn't because of budget constraints. It uses a titanium frame - this allows it to run hot on reentry, which means that heat dissipation issues aren't as serious, and damage isn't as threatening. A side advantage is you'll get a far better payload ratio.
With a titanium frame, you generally only need to protect your leading edges, and they're using RCC, which is the best material out there in the present-day for such extremes (and isn't tiles). It's expensive, but it's a one-time production run, barring damage.
Titanium frames also fatigue a *lot* less. In short, you get a safer, much lower maintainence, and longer lifespan craft. The only downside is higher initial cost.
instead of a tried-and-proven heat sheild
RCC is a tried and true heat shield. If you mean "ablatives", don't delude yourself into thinking that they're cheap, either - this will be far cheaper than ablatives when amortized over a few flights. Ablatives are costly and tricky to apply properly (just like other spray-on things, such as foam insulation) - and are very difficult to use around moving parts.
when you're planning to use parachutes to land the thing anyhow?
Parachutes don't slow you from orbital velocity. You might have noticed, if you had read, that it has wings. Do you know why? It's not to meet Buck Rogers Stylistic Guidelines(tm) - wings let you skim the atmosphere longer on reentry, burning off your heat slower. Then, on this craft, a drogue chute will fire, followed by the main chute. It's the best of both worlds - the wings can be smaller and optimized for hypersonic flight only, while they still give you a gentler reentry profile.
it's not necessarily reusable?
What cave are you living in that you didn't learn that the CEV was to be a reusable vehicle? The *launch vehicle* isn't expendible - it will probably be a modified Atlas or Delta, which are very good launch systems. Sure, I'd love to see a fully reusable booster that doesn't cost a fortune (which, by all means, should be possible), but one thing at a time.
Overall, this is a great looking craft, and it will benefit greatly from all of the research that went on from the Shuttle program (and there was a *lot* - cost-reduction and safety-enhancing research was a good portion of the Shuttle's budget). My only real question is that its hypersonic drag profile looks a bit odd. Namely, there's no visible pinch as the wings widen (drag at hypersonic velocities is largely proportional to the maximum cross sectional area, so you typically pinch the fuselage as the wings eat up more cross section). I guess I'd also like to know why they chose ethanol biprop propulsion over, say, kerosene or LOX/propane. Still, great basic design principles on this craft.
It's a Cyrillic alphabet. It's like all those keys you never push on a calculator.