pizzaandplanes
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Could The Space Shuttle Land On Water?

Sun Apr 22, 2007 11:39 pm

In the event that the shuttle would have to make an emergency landing in the ocean, could the shuttle float properly? According to the safety cards of the regular civilian aircraft, they can float in water when properly landed in water.
A real man lands where he wants to
 
zanl188
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RE: Could The Space Shuttle Land On Water?

Sun Apr 22, 2007 11:47 pm

Float? Yes. In one piece? No.

Ditching a shuttle is not thought to be a survivable thing due to its high landing speed, lack of engines, and probable break up of the airframe. Preferable option for a water landing is to bail out.
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L-188
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RE: Could The Space Shuttle Land On Water?

Mon Apr 23, 2007 12:15 am

To tell you the truth the shuttle would probably not be badly shapped for a water ditching. The problem would be the rate of decent at touchdown.

I doubt it would fly again.
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jhooper
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RE: Could The Space Shuttle Land On Water?

Mon Apr 23, 2007 2:56 am

For that matter a commercial airplane is not likely to fair well in an ocean ditching either.
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litz
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RE: Could The Space Shuttle Land On Water?

Tue Apr 24, 2007 5:39 am

I would guess that the shuttle's airframe itself probably wouldn't have much of a problem landing on water (provided the gear was not down) ... it's a VERY smooth bottom.

The problem is, soon as you hit the water, the engines and everything in the cargo bay would keep going forward, whilst everything around them didn't. Not a good situation.

Remember the shuttle is designed for max torque in a downward direction, towards the rear of the ship, as that's what it experiences on takeoff. Massively reversed forces would require so much weight to counter it would be unflyable.

- litz
 
DfwRevolution
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RE: Could The Space Shuttle Land On Water?

Tue Apr 24, 2007 6:49 am

A survivable water landing is considered impossible for the Shuttle. Litz nailed it: the de-acceleration of even a gentle splash down would rapidly exceed the strength of the cargo tie downs in the payload bay. Everything aft of the crew cabin is coming forward and would destroy the crew cabin.

If the Shuttle was capable of stable flight and a water landing was the only option, the crew would elect to bail-out.
 
pizzaandplanes
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RE: Could The Space Shuttle Land On Water?

Tue Apr 24, 2007 8:46 am

From what I read in Popular Mechanics, the old version of landing will become new. So, is this true that the new aircraft to bring astronauts to space will land in the water again?

I personally think that a spacecraft should be able to land on land and water.
A real man lands where he wants to
 
sprout5199
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RE: Could The Space Shuttle Land On Water?

Tue Apr 24, 2007 9:12 am

Quoting Pizzaandplanes (Reply 6):
I personally think that a spacecraft should be able to land on land and water.

Why? If something happens on launch, most likely its not survivable, on reentry the same. The "escape hatch" was put in just to placate everyone after Challenger. People just don't realize the extremes that any spacecraft goes through. The high mach numbers alone boggle the mind, let alone the heat. Just getting a spacecraft back into earths atmosphere is a miracle in its self, let alone landing it where you want to. And to make it able to land on water or dry ground? It would be easier to put floats on a 747.
Sorry for the little rant. Putting a man in space and returning him home is the hardest thing we can do so far. Be glad most survive to tell the tale.

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pizzaandplanes
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RE: Could The Space Shuttle Land On Water?

Tue Apr 24, 2007 10:18 am

Quoting Sprout5199 (Reply 7):

I don't mean to contradict you but with the kind of money, people, and intelligence put into the space program wouldn't such a thing seem possible. Who thought in 40 years the space program would advance this much? Of course the challenges have arisen like entering the earths atmosphere but NASA engineers have stepped up to the plate and conquered them. I think that in the future hopefully the spacecrafts sent to space will be able to land on what 70% of the earths surface is made of, along with better techniques on land.
A real man lands where he wants to
 
TedTAce
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RE: Could The Space Shuttle Land On Water?

Tue Apr 24, 2007 12:25 pm

I think If NASA could recruit a certain Jewish Carpenter it could be done. Otherwise, all above are reasonable responses in that getting out before impact is the best option
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DfwRevolution
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RE: Could The Space Shuttle Land On Water?

Tue Apr 24, 2007 2:09 pm

Quoting Sprout5199 (Reply 7):
The "escape hatch" was put in just to placate everyone after Challenger.

Not true. The egress hatch used for ditching is the same hatch used to board and disembark from the Shuttle since STS-1. The modification post-Challenger was to make a deployable boom available that would push astronauts safely underneath the port wing if they had to bail-out during atmospheric flight.

Quoting Sprout5199 (Reply 7):
Putting a man in space and returning him home is the hardest thing we can do so far.

Oh dispense with the melodrama: no it isn't. Space flight is not hard, it is just tedious and expensive. It is no miracle whatsoever that our crews return safely 98-99% of the time.

Quoting Pizzaandplanes (Reply 8):
I think that in the future hopefully the spacecrafts sent to space will be able to land on what 70% of the earths surface is made of, along with better techniques on land.

There's no reason to land an aircraft capable of controlled descent in the water. Especially not a vehicle like the STS that is intended to be re-used. And look at the replies above: to make a winged vehicle like the Shuttle capable of a water splash-down, it would require reinforcement to the point that it would no longer be capable of flight.

FWIW, the Orion CEV capsule will be fully capable of emergency water landings.
 
BEG2IAH
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RE: Could The Space Shuttle Land On Water?

Tue Apr 24, 2007 3:03 pm

All the answers can be found right here:

http://science.ksc.nasa.gov/shuttle/...nology/sts-newsref/sts_egress.html

To quote just a piece of it: "The probability of the flight crew surviving a ditching is very slim."

BEG2IAH
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Vorticity
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RE: Could The Space Shuttle Land On Water?

Tue Apr 24, 2007 3:35 pm

Quoting DfwRevolution (Reply 10):
Oh dispense with the melodrama: no it isn't. Space flight is not hard, it is just tedious and expensive. It is no miracle whatsoever that our crews return safely 98-99% of the time.

For the first time I want to disagree with you DFW... after working in the space industry for several years. It is very hard to send someone to space... and that 98%-99% survival rate is pretty abismal if you really sit down and think about it. With that type of failure rate, over the lifecycle of a space vehicle, people will die. That means every man or woman that agrees to go up is accepting risk, but their families don't feel the same. Though I'd agree it's not the hardest thing we have attempted to accomplish by far.

Quoting DfwRevolution (Reply 10):
There's no reason to land an aircraft capable of controlled descent in the water.

Back to agreeing with you  checkmark 
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vzlet
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RE: Could The Space Shuttle Land On Water?

Tue Apr 24, 2007 8:09 pm

Quoting Jhooper (Reply 3):
For that matter a commercial airplane is not likely to fair well in an ocean ditching either.

I think that sea state is a big factor. There have been a number of survivable ditchings/unintentional descents into calm water by jet airliners.
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Alessandro
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RE: Could The Space Shuttle Land On Water?

Wed Apr 25, 2007 9:37 pm

Isn´t the bottom of the spaceshuttle extremely hot? Wouldn´t it crack is cooled down in water?
Does head or tailwind contribute a lot?
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boeingfixer
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RE: Could The Space Shuttle Land On Water?

Wed Apr 25, 2007 10:01 pm

Quoting Alessandro (Reply 14):
Isn´t the bottom of the spaceshuttle extremely hot? Wouldn´t it crack is cooled down in water?
Does head or tailwind contribute a lot?

The Thermal Protection System, TPS is what absorbs the reentry energy and is somewhat hot after reentry. The basic structure underneath is not hot at all. That being said, the Thermal Tiles are very fragile and would not survive any ditching attempt, let alone the Space Shuttle itself.

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HaveBlue
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RE: Could The Space Shuttle Land On Water?

Thu Apr 26, 2007 1:05 am

Quoting Alessandro (Reply 14):
Isn´t the bottom of the spaceshuttle extremely hot? Wouldn´t it crack is cooled down in water?
Does head or tailwind contribute a lot?

It is glowing red during reentry. However the tiles cool down amazingly fast, within minutes or less. I've been to the open house for employees (my uncles work there) and they would take a tile, heat it to red hot with a blow torch, take the flame off and 20 seconds later let you hold it. It cooled off that quick. So, after slowing down to 'normal' flight speeds well after reentry has occurred, by the time it ditched the tiles would not be hot anymore.

That just addresses your question about the tiles being hot at ditching though. I'm not making a statement about whether a ditching would be successful or not, I'll leave that to the other armchair experts.  Wink
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Thorny
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RE: Could The Space Shuttle Land On Water?

Thu Apr 26, 2007 5:00 am

Quoting Pizzaandplanes (Reply 6):
I personally think that a spacecraft should be able to land on land and water.

Orion is to be capable of both. What is being debated is which will be the standard way. It looks like a ground landing will be standard, but a launch abort will require water landing. Water landing will seriously hamper reusability efforts.

Quoting Sprout5199 (Reply 7):
Why? If something happens on launch, most likely its not survivable, on reentry the same.

History doesn't support this. There have been three launch accidents involving manned spacecraft: Soyuz 18A, Soyuz T-10A, and STS-51L. Only 51L suffered loss of life. STS-107 is a borderline launch accident as well, and even there, the crew would have (possibly) survived if the damage sustained at launch had been investigated and Atlantis launched on a rescue mission.

Quoting Vorticity (Reply 12):
For the first time I want to disagree with you DFW... after working in the space industry for several years. It is very hard to send someone to space...

No, I think DFW is right. Getting into space is not that hard. Mankind put its first vehicle into space in 1944 (a V-2 rocket) and a relatively modest medium-range missile put Shepard and Grissom into space in 1961. The X-15 did it a couple of times a year or two later. In 2004, SpaceShipOne broke the X-15 altitude records for a fraction of X-15's cost. Getting into space need not be hard. Getting into orbit is presently costly and difficult, but so was going suborbital until SpaceShipOne did it.
 
deltadc9
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RE: Could The Space Shuttle Land On Water?

Fri Apr 27, 2007 5:04 am

Quoting DfwRevolution (Reply 5):
Everything aft of the crew cabin is coming forward and would destroy the crew cabin.

Maybe, but as stong as the crew compartment is, ti would probably just break up the whole thing and the crew compartment would be sent flying reletively in tact.

Quoting DfwRevolution (Reply 10):
Oh dispense with the melodrama: no it isn't.

Designing and building the vehicles and infrastructure that take us there is extremely complex and difficult, training for spaceflight is very difficult, management of the programs that involve manned and unmanned spaceflight is extremely complex, so I cannot agree.

Quoting Alessandro (Reply 14):
Isn´t the bottom of the spaceshuttle extremely hot? Wouldn´t it crack is cooled down in water?
Does head or tailwind contribute a lot?

The tiles as the poster above said would be touchable within seconds of glowing red, but they have no real sthength and are attached with glue so they would just shatter and break off.

Quoting Thorny (Reply 17):
No, I think DFW is right. Getting into space is not that hard.

For once, I dont agree with you. See above. Besides, the Shuttle was considered the most complex machine ever created at one point, then the A-380. Think of the raw effort and time involved just to get the 380 to fly muchless a space system.
Dont take life too seriously because you will never get out of it alive - Bugs Bunny
 
Thorny
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RE: Could The Space Shuttle Land On Water?

Fri Apr 27, 2007 11:40 am

Quoting DeltaDC9 (Reply 18):
Quoting Thorny (Reply 17):
No, I think DFW is right. Getting into space is not that hard.

For once, I dont agree with you. See above. Besides, the Shuttle was considered the most complex machine ever created at one point, then the A-380. Think of the raw effort and time involved just to get the 380 to fly muchless a space system.

One doesn't need the Shuttle to get into space, that's hugely overkill. Space travel itself is high-risk and costly, but so is climbing Mt. Everest. The only thing making it excessively costly is the government monopoly. The idea that spaceflight is too expensive and too risky for anyone but a government was shattered by the X Prize and the success of SpaceShipOne three years ago.

To get into space, at minimal values, you have to reach around 350,000 feet. Modest rockets carrying humans are capable of this, as demonstrated back in 1961. Scaled Composites achieved this in 2004 with a very modestly-budgeted air-launched rocketplane, SpaceShipOne, and is now building a larger derivative for paying customers. Bigelow Aerospace has a prototype inflatable structure in orbit and will soon launch a second to demonstrate its technology for orbital hotels, and is now known to be working with both SpaceX and Lockheed-Martin to develop and launch private orbital spacecraft to carry paying customers to and from their orbital hotel. Rocketplane-Kistler is developing a low-cost launcher and Space Station resupply vehicle that could later be manned. Other companies, such as Andrews and t/Space are at work on low-cost launchers and spacecraft, even though they lost NASA's Commercial Orbital Transportation Services competition, because these and other companies see potential lucrative markets for such services in the not-too-distant future.

None of these things would be happening if space were excessively costly and difficult.
 
3DPlanes
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RE: Could The Space Shuttle Land On Water?

Fri Apr 27, 2007 11:45 am

First time posting over here... I usually stay in Tech Ops...

But, there is an interesting book (can't remember the name) that compares current space exploration to the early settlers in their Conestogas and then the barnstormers. It draws parallels with the idea that each starts out with government, then the daredevils, then the general public, through to mass transit.

Getting to space -is- hard, but it isn't -too- hard, as SpaceshipOne has shown.

However, one thing that does strike me about space is the "tolerances" (for lack of a better word) involved...

Realizing that rockets are a -very- low production run affair, I still wonder why seemingly mundane things fail. I know the STS is very complex and there's lots to go wrong there, but several of the upstart commercial folks with much simpler vehicles have had recent launch failures. Even Lockheed and Boeing will have issues with Titan and Delta...

If you concede that the prototype A380 and 787 are similar to rockets (i.e. low run production), why don't they have engines falling off or guidance computers going haywire on the first flight?
"Simplicate and add lightness." - Ed Heinemann
 
Thorny
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RE: Could The Space Shuttle Land On Water?

Fri Apr 27, 2007 1:08 pm

Quoting 3DPlanes (Reply 20):
If you concede that the prototype A380 and 787 are similar to rockets (i.e. low run production), why don't they have engines falling off or guidance computers going haywire on the first flight?

They're not similar to rockets. Boeing has sold almost as many 787s, before the first one even rolls out, as pretty much all western launch vehicles built since circa 1970. You can incrementally test a 787, lots of engine run ups, low speed taxi tests, high speed taxi tests, quick hop around the airport with the gear down, then the gear up, then progressively longer flights under a varety of conditions, and hopefully get it back intact after the flight to find out what worked and what needs tweaking. Before the 787 is handed over to commercial operators, it will have flown many more times than all the world's manned space flights, probably an order of magnitude more times.

In the space arena, only the Shuttle brings back parts for inspection and analysis, but the Shuttle has rarely flown even a little bit outside of the "sweet spot" of its performance envelope. All other launchers are destroyed in the process of completing their missions, and all the engineersr have to go on is telemetry. That's what made space so hard in the past, There are signs this is about to change.
 
PGNCS
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RE: Could The Space Shuttle Land On Water?

Sat Apr 28, 2007 5:57 am

Quoting DfwRevolution (Reply 10):
Quoting Sprout5199 (Reply 7):
Putting a man in space and returning him home is the hardest thing we can do so far.

Oh dispense with the melodrama: no it isn't. Space flight is not hard, it is just tedious and expensive. It is no miracle whatsoever that our crews return safely 98-99% of the time.

I have to join the list of dissenters. Perhaps it is more routine than in years past, but easy? No way.
 
2H4
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RE: Could The Space Shuttle Land On Water?

Sat Apr 28, 2007 7:30 am




Quoting Pizzaandplanes (Thread starter):
Could The Space Shuttle Land On Water?

Heck, just leave the SRBs on, and you've got the world's fastest floatplane.


2H4


Intentionally Left Blank
 
zanl188
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RE: Could The Space Shuttle Land On Water?

Sat Apr 28, 2007 7:52 am

FYI:

Found this by accident while researching another thread.

It's a Shuttle ditching analysis done for NASA by Grumman in 1975.

http://ntrs.nasa.gov/archive/nasa/ca...asa.gov/19760003109_1976003109.pdf
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3DPlanes
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RE: Could The Space Shuttle Land On Water?

Sat Apr 28, 2007 8:51 am

Quoting Thorny (Reply 21):
You can incrementally test a 787, lots of engine run ups

True enough, but I've seen quite a number of video clips of SSMEs and SRBs being test fired... Isn't that similar?

Don't get me wrong, I think there's very few things in this world that have to function under the extremes that a turbopump faces. (PFM in there, for sure.) And I do think getting a vehicle into space has much that can go wrong, but I with some of the simpler failures or delays, I feel like I'm missing something...

For example, just looking at SpaceX and Falcon 1. They scrubbed one launch for a faulty valve on the kerosene tank. Kerosene isn't at cryo temps - are (non-cryo) space vehicle valves different from every other valve? Another launch was scrubbed due to a missed handoff between computers. Given all the stunning things folks are doing with computers (at billions of Hz no less), is it that hard to hand off from one to another? And their first launch failure was traced to a corroded aluminum nut... I would think we pretty much have aluminum corrosion and it's causes figured out by now...

I guess what I'm saying it that while the vehicles and the process may be hugely complex, these kinds of failures seem to be really basic. Yet they still happen.

Quoting Thorny (Reply 21):
All other launchers are destroyed in the process of completing their missions

This is an excellent point. I suppose one could say that on some flights a part might be just about to fail when the engine shuts down. And since you don't get it back, no one is any the wiser...

[Edited 2007-04-28 01:52:23]
"Simplicate and add lightness." - Ed Heinemann
 
Thorny
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RE: Could The Space Shuttle Land On Water?

Sat Apr 28, 2007 11:14 am

Quoting 3DPlanes (Reply 25):
True enough, but I've seen quite a number of video clips of SSMEs and SRBs being test fired... Isn't that similar?

Similar, but still an order of magnitude below what, say, the GenX will be put through before certification. Also, the Shuttles performed exactly one* 20-sec Main Engine test firing before first flight. One. That's one 20 second test of the entire vehicle in flight configuration. How many engine runs did the A380 go through before first flight?

And the SRBs? The one and only time each particular SRB is fired is when its flying that mission. After each firing, they have to be taken apart and refurbished, reloaded with propellant, and then re-stacked, and never have all the various elements flown twice in exactly the same combination. Each SRB is essentially brand new with no flight history.

*Okay, Challenger needed two due to hydrogen leaks. Columbia, Atlantis, and Endeavour had one Flight Readiness Firing. Discovery had one in 1984 and another in 1988 to verify system safety upgrades and exercise the KSC launch teams for Return To Flight after 51L.

Quoting 3DPlanes (Reply 25):
For example, just looking at SpaceX and Falcon 1. They scrubbed one launch for a faulty valve on the kerosene tank. Kerosene isn't at cryo temps - are (non-cryo) space vehicle valves different from every other valve? Another launch was scrubbed due to a missed handoff between computers.

Well, SpaceX has only had two launch campaigns so far. They've both failed, but then so did the first two Boeing Delta III's or the first two Orbital Sciences Pegasus XLs, and both enjoyed much greater budgets.

Quoting 3DPlanes (Reply 25):
Given all the stunning things folks are doing with computers (at billions of Hz no less), is it that hard to hand off from one to another?

Well, the same thing happened to the first Shuttle launch attempt in 1981. If it happens to NASA, which spent billions on the project, it isn't all that surprising it happened to SpaceX which is spending a few hundred million.

The point of all this is that companies like Scaled and SpaceX are shattering the myth that it takes billions of dollars to overcome these problems and reach space. Space is still difficult, risky, and complex, but it is no longer only the realm of world-leading governments and multi-billion dollar corporate empires.

Quoting 3DPlanes (Reply 25):
Quoting Thorny (Reply 21):
All other launchers are destroyed in the process of completing their missions

This is an excellent point. I suppose one could say that on some flights a part might be just about to fail when the engine shuts down. And since you don't get it back, no one is any the wiser...

That is why NASA still recovers the Shuttle's SRBs. The cost of refurbishment and reuse at low flight rates makes it highly doubtful NASA is saving any money. But the ability to look one over after flight is extremely valuable. That's also why SpaceX tried (but failed) to recover the Falcon 1 first stage.
 
Vorticity
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RE: Could The Space Shuttle Land On Water?

Sat Apr 28, 2007 4:59 pm

Quoting Thorny (Reply 17):
Getting into space is not that hard. Mankind put its first vehicle into space in 1944 (a V-2 rocket) and a relatively modest medium-range missile put Shepard and Grissom into space in 1961. The X-15 did it a couple of times a year or two later. In 2004, SpaceShipOne broke the X-15 altitude records for a fraction of X-15's cost. Getting into space need not be hard. Getting into orbit is presently costly and difficult, but so was going suborbital until SpaceShipOne did it.

I'm not trying to debate the symantics of what is "space" and what isn't. It is, in fact, much much easier to send someone to a sub-orbital altitude than to put someone into the exact inclination and altitude of station and successfully rendezvous the spacecraft with station then safely return the crew to Earth at a specific landing strip completely unharmed.

Statistically if you look at how many people have died trying to reach space, it is one of our most dangerous modern day scientific endeavours. And please, do not believe for one second that a single successful flight of SpaceShipOne means that going sub-orbital is easy. Shuttle made it to orbit and back many times, and people started feeling as if a Shuttle launch was routine as opposed to experimental. But as we all know in hindsight, there have been two shuttle accidents resulting in loss of life. For as much as I love Rutan, he is not without his failures either. SpaceShipOne's flight was not without errors either, but it did happened to come out on top. I don't wish to be negative, I hope by all means that Rutan's success with SpaceShipOne continues, but as an objective engineer, it still has much to prove.

It's not drama, as an objective engineer, it's risk assessment... space travel is hazardous... but I still love spacecraft, and hope it becomes safer.  Smile
Thermodynamics and english units don't mix...
 
jwenting
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RE: Could The Space Shuttle Land On Water?

Sat Apr 28, 2007 6:18 pm

Quoting Pizzaandplanes (Reply 6):
From what I read in Popular Mechanics, the old version of landing will become new. So, is this true that the new aircraft to bring astronauts to space will land in the water again?

Highly unlikely. It will have to be reusable with rapid turnaround, impossible with water landings (in fact no spacecraft that landed on water was ever used again, unless you count the SSTs boosters and those require months of refitting after every flight).

Quoting Pizzaandplanes (Reply 8):
. Who thought in 40 years the space program would advance this much?

It's not advanced AT ALL since the introduction of the Shuttle in the 1970s.
Some new technology has been introduced that was developed elsewhere and happens to have uses in space (like digital computers) but that's about it.
All attempts to advance have pretty much been sabotaged by NASA and Washington by slashing budgets and setting impossible demands that change halfway down development to ensure budget overruns.

In fact the only real advances have been SeaLaunch (rapid turnaround mobile launchpads on a ship) and SpaceShip1 (which isn't really a spaceship at all yet but has the potential to be developed into one). Of those SeaLaunch is little more than combining Soviet ICBM technology with US electronics and materials technology and Norwegian shipbuilding expertise, no real advance in technology but application only, and SS1 is as I pointed out no space vehicle at all.

If you look at the current state of launch vehicle technology you'll see that we are effectively at a level similar to Saturn 1, which is a step BACK from the height of space technology in the mid 1960s instead of a leap forward.

It's been well established that using current technology we couldn't even replicate the Apollo moon missions. We lack the heavy launch capacity and spaceship design and construction expertise (and the sheer guts to go out there in a tin can knowing there's a good chance we won't be coming back).
In part that's due to politics (lack of budget, internal strife within NASA and other space agencies), in part it's lawyers (liability in case something happens and someone gets hurt, even if those people knowingly took that risk), in part it's apathy (people just don't care).
But that's the sorry state of space travel as it stands.
IF development had gone on at even half the pace it was at in the 1960s we'd have permanent settlements on the moon and Mars by now, and probably be mining the asteroid belt for raw materials to construct the first interstellar expeditions.
I wish I were flying
 
Thorny
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RE: Could The Space Shuttle Land On Water?

Sun Apr 29, 2007 2:14 am

Quoting Vorticity (Reply 27):
I'm not trying to debate the symantics of what is "space" and what isn't. It is, in fact, much much easier to send someone to a sub-orbital altitude than to put someone into the exact inclination and altitude of station and successfully rendezvous the spacecraft with station then safely return the crew to Earth at a specific landing strip completely unharmed.

Of course. The point I'm trying to make is that, ten years ago, SpaceShipOne and its brethren were also considered too expensive, too risky, unmarketable, etc. Now, the naysayers are saying "Okay, so they got suborbital, big deal, that's a long way from orbit, it's much too difficult and too expensive to get to orbit..." How long before this argument too is shattered by Scaled Composites, Bigelow, SpaceX, t/Space...?

Quoting Vorticity (Reply 27):
And please, do not believe for one second that a single successful flight of SpaceShipOne means that going sub-orbital is easy.

SpaceShipOne, unlike any previous manned spacecraft (except X-15), was progressively test flown to greater speeds and altitudes before making its space attempts. SpaceShipOne made 17 flights, the last three of which reached over 350,000 feet and officially are spaceflights. The last two of these spaceflights occured less than a week apart, something no one else has ever done. There's a reason it is now hanging in the National Air & Space Museum.

Quoting Vorticity (Reply 27):
But as we all know in hindsight, there have been two shuttle accidents resulting in loss of life.

Both of which were completely preventable if management had simply listened to the engineers and what the hardware was telling them, instead of putting budget and schedule ahead of safety. This too is something private or commercial operators are much more likely to avoid. If NASA screws up, it goes to Congress and says "mea culpa, may we have some more money please?" (and they got it after both Shuttle accidents.) If Virgin Galactic kills passengers, it will almost certainly be out of business.
 
Thorny
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RE: Could The Space Shuttle Land On Water?

Sun Apr 29, 2007 2:39 am

Quoting Jwenting (Reply 28):
It's been well established that using current technology we couldn't even replicate the Apollo moon missions. We lack the heavy launch capacity and spaceship design and construction expertise

This is nonsense. We don't need Saturn V to go to the moon. We went the Saturn V route because we were in a hurry to meet Kennedy's 1970 deadline, and such things as rendezvous and docking were still unknowns. NASA's mantra in the early years was "waste anything but time". We wouldn't in our right minds do it this way today. Apollo was cancelled for a reason: it was too expensive. When we go back to the moon, we'll need to make it a much cheaper affair (and Project Constellation doesn't seem to be doing this at all) or it will be cancelled too.

When you look at Apollo, it was basically three things you needed: a manned spacecraft for the crew to fly to and from the moon; a lunar lander; and a rocket stage to boost you out of Earth orbit on course for the moon. The lunar lander weighed around 30,000 lbs. The Apollo CSM weighed around 70,000 lbs, but most of this was fuel. Without all that fuel, a Saturn IB-class rocket was able to launch Apollo CSMs for Apollo 7, SkyLab, and Apollo-Soyuz. The US has two rockets (Atlas 5 and Delta IV) flying today with greater payload capacity than Saturn IB, with two more in development (Falcon 9 and Ares I). There are also several international rockets in this class. The rocket stage weighed around 200,000 lbs, again mostly fuel. The great majority of the weight you need to launch is fuel. Fuel is very easily subdivided among many launches. Russia has been automatically refueling its space stations for 30 years, Progress and soon ATV are off the shelf technology. So instead of building Saturn V, you use existing rockets to launch the individual pieces and then load them with propellant from fuel-haulers. (You also create a huge rocket launch market this way, cutting the cost of access to space for everyone.)

We certainly have the technology today. Martin-Marietta in the early 1990s proposed lunar missions that would have used Titan IV, Centaur, and Shuttle to assemble the parts in Earth orbit. The only thing needed was a slightly improved Titan IV second stage to loft a fully fueled Centaur into orbit (instead of Centaur burning some of its fuel on the way up.) Delta IV Heavy and Atlas V Heavy both have greater payload than Titan IV now, so it is probably doable if we wanted to. Lockheed and Boeing both have growth versions of their rockets in design studies that wouldn't take a huge amount of effort to put into production. And of course, you probably don't want to design your Apollo-class spacecraft as big and heavy as NASA has done with Orion. Cut the weight back to Apollo-levels, and things get a lot easier.
 
PGNCS
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RE: Could The Space Shuttle Land On Water?

Mon Apr 30, 2007 6:58 am

Quoting Thorny (Reply 30):
The great majority of the weight you need to launch is fuel. Fuel is very easily subdivided among many launches. Russia has been automatically refueling its space stations for 30 years, Progress and soon ATV are off the shelf technology. So instead of building Saturn V, you use existing rockets to launch the individual pieces and then load them with propellant from fuel-haulers. (You also create a huge rocket launch market this way, cutting the cost of access to space for everyone.)

So you're back to the EOR model proposed and rejected by NASA in the 1960s. I'm not saying you're wrong, I am just very suspicious about the argument that a large number of small launchers cost less on a net basis than a small number of large launchers. The shuttle was supposed to bring the cost of a pound of payload lofted into orbit below $100, too; it actually costs around $20,000. Perhaps it's an apples to oranges argument, but perhaps not: a lot has been promised in the past that has not panned out in the light of day.
 
Thorny
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RE: Could The Space Shuttle Land On Water?

Mon Apr 30, 2007 8:47 am

Quoting PGNCS (Reply 31):
So you're back to the EOR model proposed and rejected by NASA in the 1960s.

It was abandoned then for two reasons: rendezvous and docking were still unknowns (rendezvous not demonstrated until December 1965, docking not until March 1966) and because John Houbolt came up with Lunar Orbit Rendezvous, wherein NASA decided if it needed rendezvous and docking anyway, they might as well use LOR and save a huge amount of weight.

Note that the current Constellation flight profile has both EOR and LOR. (1.5 launches, plus rendezvous upon return to lunar orbit.) Note also that LOR becomes less attractive for longer-duration missions, especially if the landing site is far from the poles.

Quoting PGNCS (Reply 31):
I am just very suspicious about the argument that a large number of small launchers cost less on a net basis than a small number of large launchers.

We won't know until we try, and it will almost certainly be cheaper to try large numbers/small payloads than it will be to develop two-flights/year Ares V. The data available seems to clearly indicate the large number/small rockets model will be much cheaper, even if it doesn't spur development (at long last) of a fully reusable launcher. And it probably would spur such development. Even if it doesn't, the greatly increased production of Atlas, Delta, Falcon what have you will cause lower prices for everyone else who needs to fly on one. There are no other conceivable payloads for Ares V, so NASA's footing the entire bill.

Look at how much NASA pays for Delta IIs: around $50 mil / flight when they ordered something like 20 of them from Boeing. Delta II is capable of 13,440 lbs to Low Earth Orbit. That's about 1/4 the payload of a Shuttle for 1/10 or so the cost. And Delta II is obsolescent technology. Falcon 9 will have more payload (rivaling Delta IV and Atlas V) but SpaceX is promising much lower costs. SpaceX is doing this despite few customers and a history of space startups going belly-up. Imagine what would happen if NASA were next year to RFP a dozen companies for, say, 600,000 lbs. (roughly two lunar missions) to LEO per year beginning in 2015.
 
PGNCS
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RE: Could The Space Shuttle Land On Water?

Mon Apr 30, 2007 10:26 am

Thorny;

I understand all about Houbolt and the history of LOR v. EOR. I also understand that both are in the envisioned future profile. Like I said in my original post, I'm not saying you're wrong, what I am saying is that many promises have been made about low(er) cost access to space in the past that haven't panned out. Sceptical is good in aerospace, it means that NASA and other users have to examine all their options to find the overall best solution. As of this moment, they seem to differ with you, but that's subject to change. I really don't care how they accomplish the goal as long as they accomplish the goal!  conehead 
 
Thorny
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RE: Could The Space Shuttle Land On Water?

Mon Apr 30, 2007 12:41 pm

Quoting PGNCS (Reply 33):
Sceptical is good in aerospace, it means that NASA and other users have to examine all their options to find the overall best solution. As of this moment, they seem to differ with you, but that's subject to change.

The problem is that it isn't at all clear that NASA chose the best solution. NASA chose to design a third new EELV-class launch vehicle (Ares I) despite the US having two which are underutilized already. They also chose a behemoth that will only fly twice a year (Ares V) guaranteeing high mission costs. Worse, the Ares I that NASA originally chose was justified as "Safe, Simple, and Soon" because of its Shuttle heritage SRB and Space Shuttle Main Engine. Well, the SSME was abandoned in short order as being too expensive, both for air-start redesigns and on procurement costs. That decision forced NASA to stretch the SRB, adding a fifth fuel casing. This made the new Ares I first stage essentially an all-new vehicle requiring a full-up development and test program. It also made an already "tall and lean" booster even taller, making control authority problems even worse. The new Ares I still seriously underperforms its original, forcing NASA to change the flight profile so that now the Orion spacecraft must fire its engine to achieve the last bit of velocity needed to reach orbit. "Safe, Simple, and Soon" is long dead.

It is also curious that earlier in his career Dr. Griffin was a major proponent of Shuttle-derived concepts, versus the more-or-less off the shelf EELV solution, and as soon as he took over NASA, the EELV options were put on the backburner. Doesn't this sound like someone already had his favorite picked out? Isn't it suspicious that NASA chose the most expensive option for return-to-the-moon, one that maintains as large a fraction of its current Space Shuttle workforce empire as possible? Did an engineer make this decision, or was it a politician?

This sounds very much like the history of the Space Shuttle, which also started out with a promising concept, but budget and design difficulties nickel-and-dimed it until it was the low-flight rate, high-maintenance vehicle we have today. After only a couple of years, Ares I is already only a shadow of the vehicle originally proposed. Will NASA come to its senses and realize that the Ares family was the wrong choice, or are we going to be stuck with it for 30 years because bureaucrats can't admit their mistakes?
 
jwenting
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RE: Could The Space Shuttle Land On Water?

Mon Apr 30, 2007 11:26 pm

Quoting Thorny (Reply 30):
This is nonsense. We don't need Saturn V to go to the moon. We went the Saturn V route because we were in a hurry to meet Kennedy's 1970 deadline, and such things as rendezvous and docking were still unknowns.

we don't have the launch capacity today to launch anything big enough...
we lack the political will to commit the resources to build it in space...
we lack the sheer guts to go out there and do it even if we did have the resources...
we lack the technology to make it there and back in a way that guarantees a safe return, which is the only thing that politicians might even consider funding and lawyers might even consider approving liability insurance for.

no, we can't do it today.
I wish I were flying
 
Thorny
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RE: Could The Space Shuttle Land On Water?

Tue May 01, 2007 1:55 am

Quoting Jwenting (Reply 35):
we don't have the launch capacity today to launch anything big enough...

WE DON'T NEED IT. Apollo was a 30,000 lb. Lunar Module (easily launchable on an EELV) and a 70,000 lbs Command/Service Module. That is heavier than what an EELV could launch, but the solution is simple: launch it with a minimum fuel load and top off the tanks in orbit, a'la Progress. A Saturn IB (smaller than today's EELV-Mediums) was able to launch a CSM with a minimal fuel load (Apollo 7 and SkyLab), and even a CSM with an extra module (Apollo-Soyuz's Docking Module.) The rest of Apollo was the S-IVB stage, which weighed around 250,000 lbs. the vast majority of which was propellant. We'd need about 10 flights of a 50,000 lbs. payload EELV-class rocket today to accomplish Apollo: 2 for the CSM (one for the vehicle and one for propellant), one for the Lunar Lander, one for the S-IVB-class Upper Stage, and about 6 for Upper Stage propellant. We'd need some tweaks to infrastructure to achieve this (probably an additional Delta Mariner and completion of the other pad at Complex 37), but nothing on the order of Complex 39 in the 60s. We could spread the launch requirements around between Delta IV, Atlas 5, Ariane V, Sea Launch, and Falcon 9. Most of the launches are just fuel.

Quoting Jwenting (Reply 35):
we lack the political will to commit the resources to build it in space...

Nonsense. ISS, if it achieves nothing else, has shown us the do's and don'ts of Earth Orbit Assembly, and most of this "build it in space" is for propellant transfer. We'd need to complete development of automated propellant transfer in space, but there are several contenders already in the pipeline. Politicians would like to have more constituents building and launching rockets, not fewer: more voters, and it cuts down the price of the EELVs the military needs, to boot.

Quoting Jwenting (Reply 35):
we lack the sheer guts to go out there and do it even if we did have the resources...

This can change in an instant. It already did once, on October 4, 1957.

Quoting Jwenting (Reply 35):
we lack the technology to make it there and back in a way that guarantees a safe return, which is the only thing that politicians might even consider funding and lawyers might even consider approving liability insurance for.

What technology, exactly, do we need that we don't have? And of course we can't guarantee a safe return. We can't guarantee your next flight on a 747 will get you where you're going safely, either.
 
DfwRevolution
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RE: Could The Space Shuttle Land On Water?

Tue May 01, 2007 4:20 am

Quoting Thorny (Reply 36):
WE DON'T NEED IT. We'd need about 10 flights of a 50,000 lbs. payload EELV-class rocket today to accomplish Apollo

And to those still skeptical of the EELV route, keep in mind two industry rules-of-thumb for space economics:

- doubling your flight rate equals a 10% reduction in flight unit cost (economics of scale)
- about 40 flights per year are necessary for a reusable vehicle to make sense

Using an EELV to launch a 50,000 lb payload requires three Delta IV or Atlas V core vehicles. Just one lunar mission per year and you have an instant market for 30 core vehicles per year. Relative to either EELV flight rate today of less than 5 vehicles per year, that yields a unit cost reduction of nearly 30% per flight. It also puts us in striking distance of practical, economical, reusable space flight.
 
3DPlanes
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RE: Could The Space Shuttle Land On Water?

Tue May 01, 2007 11:05 pm

Quoting Thorny (Reply 34):
one that maintains as large a fraction of its current Space Shuttle workforce empire

This brings up another poser that I have... Having been through the OPF hangar and seen the tile rework going on, I wonder just what those folks do when there isn't a shuttle to refurb? I mean, sure once this next launch is over and the shuttle is back they'll be busy - but right now, today, what did they do for 8 hours of pay?
"Simplicate and add lightness." - Ed Heinemann
 
jwenting
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RE: Could The Space Shuttle Land On Water?

Wed May 02, 2007 1:21 am

why do you think the interval between launches is so long?
It's because those guys take that long to refurb those Shuttles...

Quoting Thorny (Reply 36):
Nonsense. ISS, if it achieves nothing else, has shown us the do's and don'ts of Earth Orbit Assembly, and most of this "build it in space" is for propellant transfer.

nonsense. IIS is a political beast. Sure it shows we can bolt some earth launced modules together, but that's it.
It's no space construction, nothing on the scale a large program would require.
And no, it would not have to be mostly fuel transfer.
You'd want pretty much everything (certainly after the first few missions) built up there from scratch to reduce the cost of pulling everything up that massive gravity well we call earth.
That is, if you're interested in a longterm presence and not another Apollo style PR adventure to take some photographs before once again shutting everything down.

And that's the problem.
Such a venture would take more than 4 years, which means it will never get funding from a democratic government as its members are only interested in things that show a positive result on their chances of getting reelected in the next elections.

Quoting Thorny (Reply 36):
Politicians would like to have more constituents building and launching rockets, not fewer

certainly not. The environment maffia has declared that rockets are bad for the environment so noone wants to be seen as promoting them.
And yes, they are. Fully reusable launch vehicles burning LOX/LH2 (for example) are far better (also costwise if they can be made to work, unlike the Shuttle which is an economic failure) but they're unavailable (every initiative for the last 20+ years having been torpedoed by NASA for some reason, you'd almost think they don't want them) at the moment and creating one with enough payload volume will take a long time, longer than available (see above).

Quoting Thorny (Reply 36):
We'd need about 10 flights of a 50,000 lbs. payload EELV-class rocket today to accomplish Apollo

Maybe for the weight, probably more for the volume.
There's no large diameter launch vehicle available at the moment, with the retirement of Saturn and Energia.
So you'd either need to launch the larger sections in parts and assemble them in orbit (and thus launch and construct the construction rigs as well, and crew accommodation and supplies for the workcrews as well as those crews) or create a new large diameter launch vehicle from scratch.
I wish I were flying
 
deltadc9
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RE: Could The Space Shuttle Land On Water?

Wed May 02, 2007 3:51 am

Quoting Jwenting (Reply 39):
nonsense. IIS is a political beast. Sure it shows we can bolt some earth launced modules together, but that's it.

That is not it, are you completely unaware of what it is used for?

Quoting Jwenting (Reply 39):
Apollo style PR adventure to take some photographs before once again shutting everything down.

There was so much science on those 10 or so missions I dont even have the time to summarise, maybe you should do your homework before making uninformed claims like this.

Quoting Jwenting (Reply 39):
It's because those guys take that long to refurb those Shuttles...

There are other factors, many others that affect the timing. One is budgeting that allows for just a few flights a year, another is launch windows, another is crew training.

Quoting Jwenting (Reply 35):
we lack the sheer guts to go out there and do it even if we did have the resources...

Total BS. Americans and Russians have risked their lives and died for decades in their respective programs and the cue to go up keeps getting longer. Fighter and Test pilots dont have the guts? Please. Not to mention the scientist and others.

Quoting Jwenting (Reply 35):
we lack the technology to make it there and back in a way that guarantees a safe return, which is the only thing that politicians might even consider funding and lawyers might even consider approving liability insurance for.

Apollo had a 100% success rate. That is why we are returning to that basic design. DC has no problem with an Apollo type program with regards to safety.
Dont take life too seriously because you will never get out of it alive - Bugs Bunny
 
Thorny
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RE: Could The Space Shuttle Land On Water?

Wed May 02, 2007 12:15 pm

Quoting Jwenting (Reply 39):
nonsense. IIS is a political beast. Sure it shows we can bolt some earth launced modules together, but that's it. It's no space construction, nothing on the scale a large program would require.

First, I'll note that you are unwilling or unable to answer my question, "what technology do we lack that we need to go back to the Moon..."

Second, ISS is considerably greater than bolting some modules together. It is not remotely worth the cost we've put into it, but we should give credit where its due: ISS is a damned sophisticated spacecraft, with both pressurized and unpressurized elements that are by far the most advanced machines humans have placed into orbit. And these elements come from at least four different nations so far (Russia, the U.S., Canada and Italy) with more coming in the next year, so making machines from four different nations work together as well as ISS does (growing pains notwithstanding) is no small achievement. ISS has power coming from three different sources (Truss, Zvezda and Zarya) with cooling and life support being provided by two different sources (Zvezda and Quest) and pumped throughout, including sophisticated through-the-bulkhead connections on the US side (no more hoses-through-open-hatches like on Mir.) ISS has needed over 70 spacewalks to date, mostly for assembly. This is hardly "bolting two modules together."

Quoting Jwenting (Reply 39):
And no, it would not have to be mostly fuel transfer.

Actually, yes it would. You'd have to dock the Orion and the Lander together, and then dock them to the Upper Stage. That's only three dockings. Note that Russia has been automatically docking modules together for 30 years now. Everything else is fuel delivery, and Russia has been doing that for 30 years, too. Good news: Russia will sell this technology to anyone who wants it. Europe already has bought it and will demonstrate ATV-1 later this year. So even if the US fails to develop automated rendezvous, docking and propellant transfer, we can always by the Progress system if we have to.

Quoting Jwenting (Reply 39):
You'd want pretty much everything (certainly after the first few missions) built up there from scratch to reduce the cost of pulling everything up that massive gravity well we call earth.

Why? That's not how construction is done on Earth. We truck in all the pieces we need to build a skyscraper or a bridge, we don't build a factory on the skyscraper's site. What we need is low-cost transportation, not factories everywhere we go. How do we get low-cost transportation? By creating a market for it. NASA could do this today by requesting x amount of propellant delivered to orbit every year. Unfortunately, NASA has chosen to fill the market itself, by building a megarocket that only NASA will operate, dooming it to extremely high launch costs. DFW is right: it takes a certain number of flights per year (the number varies, but is around 30-40) before the expense of developing a Reusable Launch Vehicle makes sense. And if you have an RLV, the cost of space access is radically dropped. NASA could foster this development today, if it chose to. But NASA is still clinging to ancient empires (Complex 39) and is unwilling to make the bold change for this to happen.

Quoting Jwenting (Reply 39):
Such a venture would take more than 4 years, which means it will never get funding from a democratic government as its members are only interested in things that show a positive result on their chances of getting reelected in the next elections.

This is a myth. Kennedy urged Americans to "land a man on the moon before this decade is out". Had he lived, he would not have been in office when Apollo 11 landed. Space Shuttle began as a program under President Nixon, even though there was no chance Nixon would still be Presdent by the time it flew (Shuttle's maiden flight was originally 1978. Nixon would have left office (assuming Watergate never happened) in 1977. Space Station was begun under President Reagan in 1984, but wasn't scheduled to be built until 1992. Reagan left office in 1989. Bush initiated Project Constellation in 2004, with Orion scheduled at the time to fly for the first time in 2012. Bush will leave office in 2009.

Quoting Jwenting (Reply 39):
The environment maffia has declared that rockets are bad for the environment so noone wants to be seen as promoting them.

References, please. The only criticism I've seen of rockets impact on the environment has been the "Solid Rocket Boosters destroy the Ozone" myth (long ago debunked) and criticism of Russia dumping toxic rocket stages (Protons) on unsuspecting nomads and remote villagers. Atlas V (kerosene and LOX) does not use toxic propellants. Delta IV (LH2 and LOX) does not use toxic propellants. Both use solid propellant boosters in their medium-class versions, but we'd probably be talking about -Heavy versions, which don't use solids. Delta IV-Heavy is an all-hydrogen rocket (nevermind that hydrogen currently comes from hydrocarbons... the environmentalists seem to have completely missed this fact.)

Quoting Jwenting (Reply 39):
We'd need about 10 flights of a 50,000 lbs. payload EELV-class rocket today to accomplish Apollo

Maybe for the weight, probably more for the volume.

No, you can sacrifice a little payload by splitting the propellant into multiple tanks and discarding tanks during the burn (essentially the same as staging a rocket from Earth.) Saturn's S-IVB was about 21 feet in diameter, remember, and Delta IV is over 16 feet (and some hammerheading seems possible, a'la Delta III or Ares I) so the difference isn't great. The solution is fairly simple: use a three-body arrangement. A traditional core stage with a J-2X engine or two and LH2 and LOX tanks. Connected to either side are two more such bodies, sans engines. Each has propellant lines to feed the center body. (Boeing has been already been working on such an arrangement for Delta IV-Heavy.) The vehicle burns the propellant from the two outboard bodies first, and discards them, continuing the burn with propellant from the middle body. The payload hit isn't all that bad, because your discarding the empty two outboard tanks two thirds of the way out, versus the traditional arrangement of carrying the entire weight of the bigger stage all the way to burnout. This arrangement is also flexible for future upgrades with up to five outboard tanks for heavier payloads to the Moon or Mars.

Note also that the Apollo CM was 13 feet in diameter and the Apollo LM was 14 feet acros the descent stage. Both easily accomodated by Delta IV or Ariane V.

Note also that Lockheed-Martin already has fairly well-advanced plans for a wider diameter (5.4m), two-engine version of Atlas V, should we decide we really do need a wider rocket for some other reason.

http://www.lockheedmartin.com/data/assets/12461.pdf

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