This rocket was designed to lift the same payload to LEO as

>>8853071
>baguettes dont exist because i burnt a loaf
What?

>>8853071
Which logical fallacy is this again?

>>8853084
Brainlet fallacy

>>8853071
One enormous engine bigger than it's fuel tank. Trying to reduce cost. How do yuo even?

>>8853098
Just like the real Tesla, it's just a meme

>>8853084
The thing couldn't even be launched on land it was too big, and note how its way bigger than the ITS, that's how big a rocket actually has to be to lift 550 tons

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>The first stage was to be powered by a single enormous 80,000,000 pounds-force (360 MN) thrust engine burning RP-1 and LOX (liquid oxygen). The fuels were pushed into the engine by liquid nitrogen, which provided a pressure of 32 atm for the RP-1 and 17 atm for the LOX, providing a total pressure in the engine of 20 atm (~300 psi) at takeoff. As the vehicle climbed the pressures dropped off, eventually burning out after 81 seconds. By this point the vehicle was 25 miles up and 20 miles downrange (40 km x 33 km), traveling at a speed of 4,000 mph (1.8 km/s). The normal mission profile expended the stage in a high-speed splashdown some 180 miles (290 km) downrange. Plans for stage recovery were studied as well.

>The second stage was also equipped with a single very large engine, in this case a 6 million kgf (60 MN) thrust engine burning liquid hydrogen and LOX. Although also pressure-fed, at a constant lower pressure of 7 atm throughout the entire 260 second burn, at which point it was 142 miles up and 584 miles downrange (230 km x 940 km). To improve performance, the engine featured an expanding engine bell, changing from 7:1 to 27:1 expansion as it climbed. The overall height of the rocket was shortened somewhat by making the "nose" of the first stage pointed, lying inside the second stage engine bell.

>single enormous 80,000,000 pounds-force (360 MN) thrust engine

jesus

>>8853144
just a fancy paper rocket with no means of working

>>8853135
You retard, it wasn't even built. It was just a design for a sea-launching rocket. It was literally supposed to be in the water, using the water to float it upright so it could launch out of the water.

It wasn't meant to be launched from land and was never designed to do so, not because of weight but because of what NASA wanted.

>>8853357
Wouldn't launching a rocket out of the water be an absolute engineering nightmare? How could it even ignite with all that back pressure?

>>8853445
How can it even get through the EPA?

>>8853454
Good point, fuck the environment when it comes to space exploration though. I'm just fascinated by the thought process and technology behind such a launch system

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>>8853071
muh payloads

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>>8853663

>>8853663
reeeeeeeeeeeeeeeeeeeeeee

>>8853663

how in the fuck?

>>8853694
It's just a Kerbal Space Program rocket

The part that seems implausible to me is building a 1232m high rocket in the first place that doesn't just collapse under its own weight on the launchpad. We've yet to build a reinforced skyscraper that tall.

>>8853663
Is there really any benefit in such a big rocket? It seems that it would be much more reliable to mass produce smaller rockets and assemble the payload in LEO.

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>>8853071
That's nothing compared to Daedalus

>>8853733
There's a point where rockets get too big but we're not there yet. We should keep building them bigger, cheaper and more efficient for the foreseeable future.

>>8853737
Dont get it, are they sending u're moms anal beads to space???

>>8853135
>that's how big a rocket actually has to be to lift 550 tons
Sea Dragon was a pretty mass-inefficient, low-Isp design, built of cheap steel and with pressure-fed engines. Extra mass and reduced specific impulse, of course, incur large performance penalties in an orbital launch vehicle (although it gains something back from using hydrogen in its upper stage). That's why it would have needed to be about twice the mass of ITS to get a similar payload, even with ITS's costly flyback booster recovery and propulsive landing upper stage.

>>8853445
>Wouldn't launching a rocket out of the water be an absolute engineering nightmare?
No, they tried it, it's pretty easy. They were kind of surprised by how easy it was.

>How could it even ignite with all that back pressure?
Well, Sea Dragon's chamber pressure was supposed to be 20 atmospheres. You've got to go about 200 meters down before the ambient pressure reaches that level, and Sea Dragon is only 150 meters long, so it would have to be deep underwater for backpressure to prevent the propellant flowing into the chamber normally.

Whether the chamber is initially filled with air or water at startup is just something you have to account for in the design.

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I'm more interested in seeing Rockoon (balloon-booster rockets) happen. Hydrogen balloons would carry the vehicle 32 miles up where a regular rocket could accelerate it up into orbit. Basically pic related but huge.

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>>8853818
That's fucking stupid.

>>8853834
Stupidity is the basis for engineering anon.
The outrageous has worked before, it can work again so long as it is feasible.

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>>8853839
That's fucking stupid

>>8853818
why not just fill the balloons with vacuum?

>>8853866
>fill the balloons with vacuum
That's actually not an awful idea once you get up to very high altitudes. It's being studied for use on Mars (which has air pressure at the surface equivalent to very high altitudes on Earth).

When the air pressure gets low enough, a structure to support a vacuum chamber starts to work better than a balloon filled with a light gas.

>>8853071
Is that a dildo on top of a coffee cup?

>>8853663
This is a joke right?

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>>8854600
The launch of Prometheus-B, while finally enabling humans to colonize other worlds, would also go down in history as the final cataclysmic event that forced humans to colonize other worlds.

>>8853733
>Is there really any benefit in such a big rocket?
There are major benefits to scaling up rockets, just as there are to scaling up ocean ships or liquid containers. The aerodynamic resistance gets proportionately smaller. As the tank or chamber walls get thicker, they become less sensitive to defects, and surface treatments carry a smaller mass penalty. Making larger things with thicker material is far less work than making many copies of things. Structures become easier to inspect because of their size.

Once you get into space, the square-cube law means that radiation shielding quickly gets cheaper as you go bigger. The radius can also become large enough that you can simply spin it to provide artificial gravity.

This would have been a practical approach to colonizing Mars even with 1970s technology.

it's actually kind of odd this was never revisited, considering how cheap it would be to make and has so few moving parts or complexities in general.

if anyone will ever look at it again, it's spacex or blue origin

>>8853663
>allowing to
God damnit you ESL fuckers

>>8855152
Good luck getting stable combustion in a chamer that big.

>>8854683
Get the fuck off out that can't be true.

>>8855152
>requires a nuclear aircraft carrier in order to launch

>>8853663
>literally 1.5 times the height of the tallest building on the planet in 2017
lmao wat

>>8853144
>Pressure-fed engine
>LOX tank is 17 atm
>chamber pressure is 20 atm
How dafuq was that supposed to work?

>>8855891
The LOX tank is on top. It's a 150m-tall rocket. There's a rather long pipe down from the LOX tank to the chamber. LOX is more dense than water.

If it was 1 atm at the top of a 50m pipe full of water, would you expect it to be 1 atm at the bottom?

>>8855891
>>8855916

Wouldn't they use turbopumps powered by a separate combustion process to pressurise the reactants? Or does this rocket not use this technology?

>>8856557
Scratch that completely missed it was pressure fed lel

captcha
>ECTIVO Fugmann

>>8853663

I want to see Prometheus-B launch before I die.

>>8853663
How does Prometheus B have a 1/6th payload fraction to LEO

>>8856686
Good catch.

In principle an SSTO can get near one sixth of its pad mass to LEO with hydro/lox fuel and reduced gravity drag and air resistance losses from high thrust and scaling.

I think they might be counting the mass of the orbital stage as "payload", and also being overly optimistic in their model or extrapolating a trend of improving performance outside its valid range.

>>8853663
I don't even know what to say

>>8853737
wasn't daedalus supposed to be sent to space on an Orion launcher?

>>8853694
>>8854600
Kerbal Space Program mod.

>>8853818
You need speed to get into orbit not altitude. So what if we put a rocket on a train, drive the train REALLY fast and then release the rocket when it's up to speed.
>>8858006
No, but it would help.

>>8853663
DO WE EVEN HAVE LAND TO GET A LANDING PAD BIG ENOUGH FOR PROMETHEUS-B THAT WOUDN'T HAVE THE SAME IMPACT OF A FUCKING NUKE?

>>8856686
The upper stage has its own gravitational field that helps pull the first stage along.

>>8858155
We launch it from the moon. duh