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The "Real Aerospace" Thread 
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Post The "Real Aerospace" Thread
Really good article at Ars Technica on how NASA is investigating a redesigned Saturn V F-1 main engine as a booster engine for the new SLS.

http://arstechnica.com/science/2013/04/ ... k-to-life/

Essentially, they had to disassemble and reverse-engineer a 40-year-old F-1 to figure out how it works. Not sure what that says about the current state of our aerospace industry.

The F-1 is a monster, though... the largest working single-chamber liquid fueled rocket engine ever (the Russian N1 exploded all four times it was launched). "The power output of the Saturn first stage was 60 gigawatts. This happens to be very similar to the peak electricity demand of the United Kingdom."

The SLS, if it ends up using the F-1B (instead of solid rocket boosters), would have 4 space shuttle RS-25 engines on the main stage, and 4 F-1B engines on each of two booster stages.

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Post Re: The "Real Spacecraft" Thread
That was a great article. There's a follow-up to it:

The F-1B

Not only did NASA reverse-engineer the engine, one of the companies in the Advanced Booster Competition is using that data to create the F-1's successor, the F-1B. Same beast, modern tech. Fun times. :twisted:


Mon Apr 15, 2013 4:59 pm
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Post Re: The "Real Spacecraft" Thread
Yes, just got through reading the second article. A good discussion of the reasons behind using kerosene in booster stages for the energy density, and liquid hydrogen in the upper stages for the efficiency.

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Post Re: The "Real Spacecraft" Thread
Rocketry is a fascinating topic. It seems so simple: get some fuel and oxidizer, put them in a tube with a nozzle on one end and light it off. But, it's so much more difficult than that. So many things to balance, so many tradeoffs to be made. The author's analogy of the rocket being "hammered" through the atmosphere is very appropriate.

And, I don't know about you, but I found this article to have the best description of specific impulse I've seen to date.


Mon Apr 15, 2013 7:58 pm
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Post Re: The "Real Spacecraft" Thread
Arioch wrote:
Essentially, they had to disassemble and reverse-engineer a 40-year-old F-1 to figure out how it works. Not sure what that says about the current state of our aerospace industry.

Nothing, because that´s only relevant for historians/museums.
Today we must make engines with todays standard of tech (laser- vs rodwelding, 5-axis CAM-tools vs handdrilling etc pp).
Or were you insinuating that they even don´t understand basic rocket tech anymore? :mrgreen:


Arioch wrote:
The F-1 is a monster, though... the largest working single-chamber liquid fueled rocket engine ever (the Russian N1 exploded all four times it was launched).

That´s kinda vague since the N1 had 30 engines vs Saturn 5s 5 F-1.
One F-1 has a thrust of IIRC 6.7 Meganewton, but the russian RP-170 has 8 Meganewton. Since it is Energijas mainengine and has made two succesful flights (100% successrate, like the F-1) it is the world strongest Rocketengine.
The WHOLE Saturn-ROCKET has more thrust, yes, but not the single engine.
As i always say - don´t fall for your own PR...

;)

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Mon Apr 15, 2013 9:56 pm
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Post Re: The "Real Spacecraft" Thread
Mr Bojangles wrote:
That was a great article. There's a follow-up to it:

The F-1B

Not only did NASA reverse-engineer the engine, one of the companies in the Advanced Booster Competition is using that data to create the F-1's successor, the F-1B. Same beast, modern tech. Fun times. :twisted:

Honestly? That´s a dead end.
That F1-B thingy is everything but "modern". It´s a joke.
It´s the piss poor performance parallel in rockettech to the ever recurring undead Winchester 73 zombie clones in gun tech. Yawn, good night, America...

Plus it´s prone to be a failure since those scholar-smartasses "optimized" all safety margins away. Moneyquote: "Because they didn't have the analytical tools we have today for minimizing weight, everything was very robust,..."
Yeah, sure, buddy. What could POSSIBLY go WRONG??


Ok, oldschkoool engineers like me could rant for hours about that.
So let´s better offer some constructive criticism (tm). :mrgreen:

How does a really modern engine look like? Well, if you don´t want to burn Trillions of tax money until those students´ smartasses learning curve starts to rise, you could simply buy RD-170s.
Or, which is to be preffered, leave it to the Germans.

So how would we make it? "Smartass Students"(tm) would say, we need 8 Meganewtons per unit.

So my humble little self would utter sth like "O RLY?" then. :mrgreen:

Because, let´s have a look at the basics first: Saturn Vs mass was 3000tons (so roughly 600tons per F-1), and it deployed only 43tons to the moon, about 1.4 percent or 1/70.
This is a lousy number.
Why so?
Because the Big V lacked boosters.

According to Tsiolkowskis calculations (i made an excelsheet once to play around with stagemasses and different fuels) there´s more possible. With the right fuels and the right massrelations between the stages up to 2.2% or 1/45.
Also, with todays materials we don´t need 43tons to the moon. Let´s be conservative, and say 35 tons at a rate of 1/50 is sufficient (lot´s of safety margin here).
That makes 1750 tons, or about 60% of Big Vs mass.

And since we have boosters now we split our need of first stage engines into six units (two under each barrel), which have to lift slightly less than 300tons each, compared to Big Vs 600t/each.
Makes roghly 3.3 Meganewton per unit, which really eases work on them.

Ok, what wonderfuel (sic!) do we use? Well, liquid methane and LOX.
Why so?
There are a lot of reasons, but the two most important are specific impulse (30% more than RP-1) and then physical characteristics: Almost same density AND temperature as LOX! No need for two different technologies anymore, same pumps, plumbing, sealings, dimensions whatever in both systems.
Makes it less complex and much much more compact, which again saves construction weight and in iteration overall weight and so on.

Why doesn´t somebody use Liquid Methane yet? Well, that was a political decision by some oil-sponsored white collar cretin in Washington, DC...
And the russians? Well, that´s more complicated, but it has to do with a lot of personal quirks and jealousy among the shanghaied german engineers and the russian ones at the bginning (after WW2), and later on with a lot of more complications. Or in other words: SNAFU.
...

Ok, now we have our target power output and our fuel, and since we´re Germans and not smartass blockheads, we will make an engine that pretty much will look like a 50% upscaled version of the SSME. Bang.

That means staged combustion, maybe even full-flow staged combustion if that will work at this size, to get the absolute maximum.
The F1B-dud OTOH would rely on a simple exhaust gas generator design, giving away ANOTHER 15% of specific thrust... (insert rolleyes here :mrgreen: )

Very probably these engines would be reusable, coming back from the 1st- and boosterstages via parachute and airbags. 10 or 20 launches per unit should drastically reduce cost.

Oh, and BTW, 300tons of thrust is a smart number, which can be arranged/combined into a lot of useful rockets for all purposes, from heavyweight LEO via GEO to planet missions. I can elaborate further on that once i find my papers and that exceltool.

...

Ok, but enough german brilli^H^H^H^arrogance for now, i´m pretty sure you all have questions? ;)

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Mon Apr 15, 2013 11:29 pm
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Post Re: The "Real Spacecraft" Thread
Trantor -

Did you even read the linked articles? They're not looking at it because it's the most efficient, most advanced, most powerful rocket engine. They're looking at the F-1 because it works. It's proven technology that has never had a mission-scrubbing incident. Never once did one explode on the launch pad, or experience an issue that lead to abort of a launch.

All the work that the two articles described was done to see what those "old school" engineers did right (because they did do something right). Some of those engineers were even involved in this project! The idea being that the engines can be improved using modern materials and techniques. Does this mean there will be absolutely no problems? Of course not; anyone that's serious about rockets knows how spectacularly they can fail (Americans, Russians, even Germans). However, building upon proven technology is usually not by default a "bad thing."

The overall idea behind the SLS is "if it works, go with it." So, it'll likely use several RS-25s (of which there are many still around), and either the Shuttle SRBs, or maybe F-1B liquid-fueled boosters. This will allow NASA to leverage its existing knowledge and capacities, and with the addition of a growing private space launch capacity, this seems a good path to follow.

Also, Arioch isn't wrong about the F-1 being the most powerful single-chamber liquid-fueled rocket engine built and flown to-date; it is. The RD-170 had four chambers.


Tue Apr 16, 2013 12:09 am
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Post Re: The "Real Spacecraft" Thread
Mr Bojangles wrote:
Trantor -

Did you even read the linked articles?

Sure, or where do you think the quote comes from?


Mr Bojangles wrote:
They're not looking at it because it's the most efficient, most advanced, most powerful rocket engine.

Nothing of that except the power. It´s an inefficient dinosaur.
A breaktrough then, yes. But history today.


Mr Bojangles wrote:
They're looking at the F-1 because it works. It's proven technology that has never had a mission-scrubbing incident. Never once did one explode on the launch pad, or experience an issue that lead to abort of a launch.

So what? That´s like saying "Horses never burnt because of a leaking tank. Let´s not develope cars, stick to the horse!!1!"


Mr Bojangles wrote:
The idea being that the engines can be improved using modern materials and techniques.

AAAAAAAAAAAAAND zhis iss ze werry WRONG approach.

No sane person would adapt modern tech/materials to an old (and crappy) design.


Mr Bojangles wrote:
This will allow NASA to leverage its existing knowledge and capacities, and with the addition of a growing private space launch capacity, this seems a good path to follow.

This is a dead end and will result in trillions of wasted tax money. Leave it to ze Germans:
Image


Mr Bojangles wrote:
Also, Arioch isn't wrong about the F-1 being the most powerful single-chamber liquid-fueled rocket engine built and flown to-date; it is. The RD-170 had four chambers.

Splitting hairs... :roll:

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Tue Apr 16, 2013 12:26 am
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Post Re: The "Real Spacecraft" Thread
Arioch wrote:
Essentially, they had to disassemble and reverse-engineer a 40-year-old F-1 to figure out how it works. Not sure what that says about the current state of our aerospace industry.
Probably says that the documentation was either shoddy, or just not clear enough for what they were doing. I won't explain my source, but I know that a major long-lived IT product from a major corporation (most of you have probably never heard of it, yet directly benefited from it) needed to have critical pieces reverse-engineered a few times because the engineers who knew to use component W from company X instead of almost identical component Y from company Z had retired. I don't know it for a fact (my information source has since moved to other pastures) but I've heard it implied that they had to do it again in the last few years (yes, I'm talking about a currently available product).

There's also the fact that book-learning isn't reliably a way to make knowledge "real". Actually seeing the equipment and how it fits together can do a lot to cement that high-level knowledge, potentially even better than VR (though admittedly, I'm not certain anyone has managed definitive studies yet).

Trantor wrote:
Mr Bojangles wrote:
They're not looking at it because it's the most efficient, most advanced, most powerful rocket engine.

Nothing of that except the power. It´s an inefficient dinosaur.
A breaktrough then, yes. But history today.
Do you keep track of NASA at all? ESPECIALLY with their track record, better something Ok now, than something Great never.

Trantor wrote:
Mr Bojangles wrote:
They're looking at the F-1 because it works. It's proven technology that has never had a mission-scrubbing incident. Never once did one explode on the launch pad, or experience an issue that lead to abort of a launch.

So what? That´s like saying "Horses never burnt because of a leaking tank. Let´s not develope cars, stick to the horse!!1!"
At the current rate, if NASA tried to design a car it would result in an Edsel would get 4 miles per tank if not for the fact that it would never leave the drawing board.

Trantor wrote:
Mr Bojangles wrote:
This will allow NASA to leverage its existing knowledge and capacities, and with the addition of a growing private space launch capacity, this seems a good path to follow.

This is a dead end and will result in trillions of wasted tax money. Leave it to ze Germans:
Image
If you want to build a new rocket, then get the EU to fund it.

Quite frankly, if I were a member of congress then around when the space shuttle was retired, I would have pushed for the entire Saturn 5 to be temporarily reactivated for precisely the "we already know it works" principle. Two successful test flights (or maybe even one) would likely be enough reverse-engineering iteration to nail down what needed to be done to build them in a "usable for unmanned launch" state.


Tue Apr 16, 2013 4:09 am
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Post Re: The "Real Spacecraft" Thread
[post deleted] Trantor, if you can't post in a civil manner, then don't post here. If I have to delete another flame post or close another thread because of you, I will simply ban you from the forum. There will not be another warning.

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Post Re: The "Real Spacecraft" Thread
Mr Bojangles wrote:
Rocketry is a fascinating topic. It seems so simple: get some fuel and oxidizer, put them in a tube with a nozzle on one end and light it off. But, it's so much more difficult than that. So many things to balance, so many tradeoffs to be made.


Tell me about it *Kerbal rocket exploding behind him* What did go wrong this time!


Tue Apr 16, 2013 3:22 pm
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Post Re: The "Real Spacecraft" Thread
Exploded? Add struts and more rockets.

Image


Tue Apr 16, 2013 6:44 pm
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Post Re: The "Real Spacecraft" Thread
Arioch wrote:
[post deleted] Trantor, if you can't post in a civil manner, then don't post here. If I have to delete another flame post or close another thread because of you, I will simply ban you from the forum. There will not be another warning.


What'd he do?

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Post Re: The "Real Spacecraft" Thread
CJ Miller wrote:
What'd he do?

He went a flame too far. The matter has been dealt with, so let's not gum up the thread with it. You can PM me if you have concerns, but there's really nothing to be concerned about.

Nemo wrote:
Exploded? Add struts and more rockets.

I take it then that KSP still doesn't appreciably model atmospheric drag. :D

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Post Re: The "Real Spacecraft" Thread
I appreciate the modeled cherry red glow of the burning air wrapping around my stock parts ship during the ascent. I also appreciate the copious amounts of duct tape which easily over comes it.


Honestly though, only real affect I can think of is youll break off your solar panels if you extend them prior to launch, but only because you cant duct tape (strut) them. Otherwise its just a fuel efficiency issue, which is just a fancy way of saying you didnt strap on enough rockets.


Tue Apr 16, 2013 11:12 pm
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Post Re: The "Real Spacecraft" Thread
Arioch wrote:
CJ Miller wrote:
What'd he do?

He went a flame too far. The matter has been dealt with, so let's not gum up the thread with it. You can PM me if you have concerns, but there's really nothing to be concerned about.

Nemo wrote:
Exploded? Add struts and more rockets.

I take it then that KSP still doesn't appreciably model atmospheric drag. :D



Nope that in update .20 or .21 (we are at .19)

But they did add atmospheric effect. With 2 other mods you could add a lots more realism.

Deadly reentry (do i need to explain?)
http://www.youtube.com/watch?v=8ovbMe6Sboo
and
Ferram Aerospace Research that add a lab to test aerodynamic and add the said effect on it
http://www.youtube.com/watch?v=VKX22RhqC60

Yes i like how Scott Manley do is test and youtube video, always adding some interesting space trivial.


Wed Apr 17, 2013 12:34 pm
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Post Re: The "Real Spacecraft" Thread
I like the RCS animations.

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Post Re: The "Real Spacecraft" Thread
Karst45 wrote:
Mr Bojangles wrote:
Rocketry is a fascinating topic. It seems so simple: get some fuel and oxidizer, put them in a tube with a nozzle on one end and light it off. But, it's so much more difficult than that. So many things to balance, so many tradeoffs to be made.


Tell me about it *Kerbal rocket exploding behind him* What did go wrong this time!


Between Kerbal and actual models, I have sent many a rocket to its fiery doom. :D

Nemo wrote:
Exploded? Add struts and more rockets.

<image snipped for brevity>


I am dying of laughter! Simply amazing. :lol:


Wed Apr 17, 2013 3:14 pm
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Post Re: The "Real Spacecraft" Thread
Unfortunately Saturn V and SLS are also very silly rockets. The former was built to win a race (very well built as it happens, but it's still a silly optimisation metric) and the latter is being built to maintain NASA's work force (concentrated, incidentally, in two politically powerful states) which has historically been it's biggest defense against major programme cancellation. No one wants to sack 20,000 people in Florida and Texas when a major elections are always less than two years away.

There are many ways to give NASA more capability, but almost none of them require the LC-39 launch complex that those 20,000 jobs revolve around. It's been twenty sodding years since NASA has allowed itself to imagine a future (DC-X/X-33 in 1994) that required genuine institutional reform and didn't depend on a facility built for the needs of 1960s America. This has had the unfortunate effect of crippling NASA's ambitions. Forty years ago its major ambitions were building a space plane, building a space station, and going to mars, and there has been almost no change or growth in its long term goals since then.

If you want a modern version of the F-1 engine, the closest you'll get is the Merlin engine, which is actually flying, and evolving towards the D varient. If (and it's looking more like when) Falcon 9H flies, and if (and again, it's looking more like when) Space X solves the reusability problems, then Merlin-D will be as close as we ever want to get to the F-1. 8-)


Wed Apr 17, 2013 7:39 pm
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Post Re: The "Real Spacecraft" Thread
What is it specifically that you think is silly about SLS? If you want to put large payloads in orbit, then you need some kind of reliable, low-cost heavy lift rocket. Neither a spaceplane nor a DC-Y could fulfill this role. What's your alternative to something like the SLS?

I'm as sad as anyone about the abandonment of the DC-Y, but it was intended to lift relatively modest payloads around 9,000 kg, whereas the SLS is intended to lift payloads of between 70,000 to 130,000 kg. It's hard to build space stations or interplanetary exploration vehicles 9 tonnes at a time.

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Post Re: The "Real Spacecraft" Thread
Well, as anticarrot mentioned SpaceX, he might be thinking of the Falcon Heavy project as a near-match for dreams of SLS spec lift capacity. For the moment it appears the success of the already delayed deployment of FH is pending on the successful demonstration of the upgrades developed for the Falcon 9, which should be launching with the preformance and manufacturing process improved engine upgrade sometime this summer.

Not to sound too much like a crash-craving spectator, but the whole cluster of modifications that are expected to be rolled out with the uprated F9 version 1.1 have quite a bit of exitement potential. If nothing else than a dramatic outcome of the first test of post-jettison first stage aerobatics whether it's a flop OR a success. That, and if things go as planned americans will have cheaper space launch than Proton-M! Us poor Europeans are left playing with launch costs per unit mass twice as high :o

Considering how safety concious (despite driving perhaps the most competitive launch price for a new rocket family yet (that I've been able to find anyway)) that particular rocket manufacturer is, betting on catastrophic failure on their next flight doesn't seem like the good choice.


Despite the suggestion that FH would be trying to share much of it's hardware with the F9 colleague we might, for the sake of argument, view Falcon Heavy and the Space Launch System projects as ideas on paper.
Code:
FH       vs SLS:
53       vs 70...130 kg (thousands) Mass to LEO
83...128 vs 500  $ (millions)
Soon     vs Maybe Later
Viable   vs To Be Finanially Proven
Safety-oriented VS solid rocket boosters
:P


As for the usefulness of resurrecting Saturn technology? Well, those things weren't engineered to be cheap either.

Whether we believe them or not, SpaceX is claiming to be on the crusade to develop cheap, safe, marinized and reusable (Merlin 1C or 1D (I forget which) have been claimed to be useful for up to 20 launch test burns) launch vehicles, and re-entry cargo return vehicles. NASA certainly seems to be buying their sales pitch.

Orion crew capsule is probably going to beat the DragonRider to the first manned flights tho. Wel'll have to wait and see how well the ideas for Dragon-derived robotic missions other than cargo-ferry will work out aswell.

Slightly related topic:

How soon after a company filing a patent is it readable by the general public? Just wondering how much more easy it might be for hardcore rocketry fans to keep track of space-launch companies' tech developments if company X were to file patents.

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Wed Apr 17, 2013 10:48 pm
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Post Re: The "Real Spacecraft" Thread
Arioch wrote:
What is it specifically that you think is silly about SLS?
A launch vehicle should be designed to put stuff into orbit as cheaply and reliably as possibly. The SLS was required to use components from the shuttle; a launch system characterised by it's expense and unreliability. There is a reason it is nicknamed the Senate Launch System.

Quote:
If you want to put large payloads in orbit, then you need some kind of reliable, low-cost heavy lift rocket.
This is an error. Large and heavy are not the same thing. Size pre deployment and post deployment can also very by an order of magnitude. But beyond that... What payload are you thinking of that cannot be broken down into 50 or 30 ton pieces? And that's a question even NASA can't answer.

When they do it's circular logic. "The moon lander we specificallydesigned for the SLS won't fit on a smaller vehicle so we need the SLS." Here's a challenge. Sit down and do the maths and work out how much useful payload your choice of upper stage can softland on the moon from lunar orbit. It'll be far in excess of NASA's severely self-censored dreams. We don't need custom hardware for every single application. One patch of vacuum is completely identical to another patch as far as a rocket engine is concerned.

Quote:
Neither a spaceplane nor a DC-Y could fulfill this role.
The DC-Y wouldn't need to launch a lunar lander. The DC-Y could BE a lunar lander (with 30 tons of cargo) via direct-return, aerobreaking and an orbital fuel depot. That would take about 40 launches (mostly for fuel) which wouldn't be a particular problem for DC-I if it functioned as advertised. As for space planes, Reaction Engines has plans for a MArs transport. So they apparently disagree with you. :P

Quote:
It's hard to build space stations or interplanetary exploration vehicles 9 tonnes at a time.
Explain please, with examples. Because we build EVERYTHING ELSE HUMANKIND HAS EVER USED out of pieces smaller than 9 tonnes. Sorry, but this claim really don't hold water, and it's immensely frustrating to see it repeated over and over again.


Thu Apr 18, 2013 3:34 am
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Post Re: The "Real Spacecraft" Thread
Well, technically, the component bolts and nuts and pannels only weigh in at ounces to pounds each, why use nine tons! Thats too big! There is a cost associated with building in situ versus doing it prefab under controlled conditions. Every time you have to launch a new piece, every time you have to put those pieces together in space wearing a suit, theres a great deal more that can go wrong. More variables, more possibility for failures, more things that cant be tested properly before hand. It introduces more risk into the program, and these programs are inherently risk averse.

Larger / more massive constructions will have capability and redundancy smaller units do not. You chose the lander in your earlier example, the Apollo 17 mission brought a grand total of 110.5 kg of samples back with them. The Altair program was looking to increase sample capacity to as much as 800 kg, or more if possible. Again, risk aversion comes into play. 2 of the 17 Apollo missions failed, one resulted in the total loss of the crew. Assume for a minute the same failure rate held true today. You want 800kg returned at either 100 kg per mission or 800 kg per mission. Youre looking at what, a 36% chance the 8 missions required will go right, and a 50/50 shot of the total loss of crew? Thats not really a fair comparison, we engineer things a bit differently these days. Lets take the failure rate and cut it to a third of what it was. 72% chance of success. Ok, still too low. The shuttle had a much better service record with 2 failures in 135 shots, both total crew loss events. Using that metric theres an 88% chance of success of your 8 missions and a 11% chance you lose a crew.

Anything which serves to reduce risk is going to be worth a great deal, not just because of the human or financial loss involved, but the political cost as well. Todays societies are totally risk averse, and its reflected in our governments.

edit: Consider this also
Image

Skylab was built on the ground and launched as one piece, with SL-2 performing some repairs to make it functional. How much time and how many cost over runs were involved in building the iss again?


Thu Apr 18, 2013 10:09 am
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Post Re: The "Real Spacecraft" Thread
anticarrot wrote:
Explain please, with examples. Because we build EVERYTHING ELSE HUMANKIND HAS EVER USED out of pieces smaller than 9 tonnes.

I don't know if you followed the assembly of the ISS, which was built ~20 tonnes at a time, but it took 13 years and was a bit of a mess. Assembling things in orbit is difficult and expensive and fraught with problems. The most trivial assembly tasks have to be over-engineered (removing a plate with 10 screws on it becomes a complex task requiring hundreds of hours of preparatory engineering, specialized tools, hundreds of hours of astronaut training and practice, and up to several hours of a spacewalk). A single stripped screw can (and did) become a crisis requiring several additional spacewalks and ground crew and space crew time amounting to millions of dollars. A single dropped bolt can become a hazard that now must be tracked in its own orbit by ground control. Some problems could require additional launches to correct (when you don't have the right tool on hand).

Even on Earth, the way to lower costs in construction is to pre-assemble as much as possible in the factory and do the minimum of assembly on-site. I don't see any cost savings in breaking a spacecraft or station into many parts and trying to assemble in orbit.

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Post Re: The "Real Spacecraft" Thread
Arioch wrote:
I like the RCS animations.



i think they have been around since .16 well at least they were when i buyed the game in 2012

Arioch wrote:
I'm as sad as anyone about the abandonment of the DC-Y, but it was intended to lift relatively modest payloads around 9,000 kg, whereas the SLS is intended to lift payloads of between 70,000 to 130,000 kg. It's hard to build space stations or interplanetary exploration vehicles 9 tonnes at a time.


well true, but it also depend on how much your 9 tons cost to orbit.

If it 10 time less expensive then you may want to make many flight instead of one big flight.


But am being hypocrite here i tend to just launch the biggest payload i can in one shot and if it fail too many time, i split it in 2 until it small enough to go orbit.

but it more because 1: there is no money in this game yet 2: it take way too much time to dock thing for only a game 3) i like to see thing explode because of too much structural stress :P


Thu Apr 18, 2013 2:52 pm
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