Grand Ship Builder

How effective would the "rocket ship" be?

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How effective would the rocket ship be, you know, the stereotypical rocket you think of if you are new to rockets. A circular window. Fins that can also act as landing legs, red, and pointy. AKA these things:

Rocket-ship-animated-223x300.jpg

So I was wondering, just how effective would these things be? Could they land on the Moon, or even get in orbit? They appear to be single stage.

Any posts explaining this will be appreciated.

 

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Assuming that the window is about 12 inches, they would make a nice display model. Not much else. There is almost no room for fuel and electronics, meaning that this rocket wouldn't get very far.

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If it's a conventional chemical rocket then it wouldn't get very far at all - there's simply not enough room in there for propellant. If it's some kind of super duper fusion powered rocket then it might get a bit higher but again, propellant storage would likely be a problem.

You just need to compare it to any real life rocket, or heck, any rocket you might build in KSP.

As for getting to the Moon - have a look at this drawing. Notice how much of it is rocket and how much of it is crew cabin...

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12 hours ago, Grand Ship Builder said:

How effective would the rocket ship be, you know, the stereotypical rocket you think of if you are new to rockets. A circular window. Fins that can also act as landing legs, red, and pointy. AKA these things:

Rocket-ship-animated-223x300.jpg

So I was wondering, just how effective would these things be? Could they land on the Moon, or even get in orbit? They appear to be single stage.

Any posts explaining this will be appreciated.

 

No, just, no, it looks way to heavy with unnecessary mass for space flight, and judging from the window, not enough fuel to even get on a sub-orbital trajectory

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OK, let's address the propellant/scale problems:

eHNHJpB.png

How about now?

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Nice photoshop there! 

Lets say the top red part is 9 feet tall, becuase 12 in window. That means the third silver part is about 12 feet, second is 14 feet tall, and the first is 11 feet. The rest is engine, 4.2 feet tall. 

Assuming an average of 10 feet across, we can say that it holds 580.9 cubic feet of propellent. 580.9 ft^3 is 4345 US gallons, or 16468 liters. 

If we are assuming it is made of modern materials i.e. aluminum alloys, the body would weigh 219285 lb, or 99466 kg. 

A LOX/RP1 engine would need those propellents, and so we have 4626 L of RP1 and 11842 L of LOX. 

The 4.2 foot tall, 10 foot diameter engine... I could not find any numbers on it. No one in their right mind would make an engine like that... Suffice to say it would have a relatively low ISP and thrust for its size and weight. 

If someone could run the final numbers, i dont have that kind of knowledge. These are the basic numbers, feel free to expand on them or contradict!

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What is this, a rocket ship for ants?! 

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Posted (edited)

If talk about the original version, maybe we should refer to a good sample of this rocketship:

Spoiler

30cab5352d53ccb6e7b6265a9cbeec85.jpg

Also, some IVA details.

Spoiler

a032d2dcd45ff9bc17fe6b40c363eeb5.jpg

9179149_qa-with-sf-intl-film-fest-award-

And

https://ideas.lego.com/projects/4a334bf4-589f-4f3a-83d0-598d0acc5292
 

Also, we can measure how much time it takes for them to reach direct ascent trajectory and maybe make some calculations.

(I should find this documental first.)

Edited by kerbiloid
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The legendary rocketship is the result of writers and artist looking at a thing from its cover and building from there. The legendary rocketship is obviously derived from the V-2, a small sized rocket a human could make its home or 'tent'. The main reason why people ignore staging is because it makes it look limited and complicated, a V-2 is not only human sized and compact, but its also looked simple.

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Some of my earliest ships were (loosely) based on the old 1960's sci-fi style "rockets" and come to find out, they were very good ships in the game.

NcCGpjk.jpg

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Posted (edited)

Here, i made a comparison. On the right you have the legendary rocketship and to the left you have a realistic scale legendary rocketship. The Realistic Scale on might be able to get into orbit.

unrealistic_vs_realistic_rocket_scale__b

Edited by NSEP

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Posted (edited)

The liquid oxygen tank should be about 2.5 times bigger then the RP1 tank due to correct burn ratios. 

Quote
Oxidizer to fuel ratio‎: ‎2.56

‎-Wikipedia 

 

Edited by Benjamin Kerman

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STS003 safely landed!

The closest thing I've done to it in KSP. Stock parts and stock Kerbin, built with FAR. Using a combination of whiplashes and rapiers it will SSTO with no payload, but I normally used it with a lifter akin to a shuttle. Landing it is tricky but obviously possible.

Of course making an SSTO is a lot harder on Earth. I don't think it could be done with current engines, but an advanced jet/rocket hybrid or nuclear thermal engine would probably do it.

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7 hours ago, NSEP said:

a small sized rocket a human could make its home or 'tent'

(A very small human, as A-4 is just 1.65 m in diameter.)

Early rocketships had a shape of artillery shell, as they were descendants of "from cannon to the Moon". idea.

Like this one.

Spoiler

FutureRocket.jpg

 

Later they were equipped with rudimentary wings/fins to launch them as a rocket from a railway ramp.

Spoiler

 

 

Also as aviation was quickly evolving, hybrids of a plane and a rocket were popular.

Like this one.

Spoiler

3e7cf443b582bc63836aff53d45ec045.jpg

 

Probably, A-4 has given its proportions to the classic rocketship.

But the problem with fin edges made the artists to experiment with rounded fins, engines on fins, etc.

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2 minutes ago, kerbiloid said:

(A very small human, as A-4 is just 1.65 m in diameter.)

Early rocketships had a shape of artillery shell, as they were descendants of "from cannon to the Moon". idea.

Like this one.

  Reveal hidden contents

FutureRocket.jpg

 

Later they were equipped with rudimentary wings/fins to launch them as a rocket from a railway ramp.

  Reveal hidden contents

 

 

Also as aviation was quickly evolving, hybrids of a plane and a rocket were popular.

Like this one.

  Reveal hidden contents

3e7cf443b582bc63836aff53d45ec045.jpg

 

Probably, A-4 has given its proportions to the classic rocketship.

But the problem with fin edges made the artists to experiment with rounded fins, engines on fins, etc.

1.65 meters in diameter is not that small actually. An avarage male could just barely by a small fraction spread out their arms wide enough in a 1.65m wide space. And dont forget that the V2 is 14 meters tall, thats like a two story building.

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Part of the appeal of the "classic" spaceship can be placed upon the shoulders of Heinlein. He used ships of that style for many of his earlier stories... though the transfer ship in "Farmer in the Sky" was refreshingly realistic.

Keep in mind, many of the stories using ships of this design are torchships, aka "silly physics, you have no power here" ships. :wink:

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Posted (edited)

Using fins as a landing leg is not exactly a good idea when you built a rocket. The crew cabin is far too large in comparison to the overall size. Most of these rocket is based from V2 rocket, and writers stuck with that shape. For modern era, this is less a shape of rocket, more like a modern day aircraft bombs

Edited by ARS

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I whipped up a craft in a few minutes as a hypothetical. In fact, I called it the "Hypothetical." I retained the same basic shape with all stock parts, mirroring the shape of the clip art as closely as I could. Came up with this:

 

Spoiler

Yqjrd67.png?1

 

Around 2,500 m/s. Not quite enough to get into orbit, but the TWR was extreme so of course I gunned it going straight up with all the orange suits inside.

 

Spoiler

eGabUGw.png?1

 

However, I was encouraged by that number. 2,500 m/s of delta-v? Surely I could squeeze it out somewhere. I made a few refinements, higher ISP engine, and used every possible fuel space. I used no part clipping other than to cheat a tiny bit by squeezing two toroidal fuel tanks into the tippity top of the rounded nose cone, as it couldn't store fuel. The top section, right above the hitchhiker capsule, is a C7 brand 2.5-1.5m adapter, because it holds fuel and oxidizer.

Spoiler

fyg4hRm.png

 

At this point I was like Holy crap, this might just be possible. It was so tantalizingly close to be  able to make orbit, and while all of these designs had the guts to get into space, none would make orbit.

Then it hit me- fairings. Use a fairing for the upper body, and stuff as many fuel tanks as possible as I could. So I did just that. Yeah, a little cheaty, but the point was to keep the same basic body shape while still having as much fuel in there as possible. I pretended that the fairings were solid pieces that contained fuel tanks. Besides, you can't tell from behind a fairing anyway. Shush.

 

Spoiler

vGIt7UN.png

 

Then guess what happened?

It worked. It freakin' worked.

 

Spoiler

gbKkYm9.png

Spoiler

mycc4dk.png

 

Way, waaaay back a long time ago, I did the K-Prize challenge and got a badge by the skin of my teeth. This vehicle, this thing I hammered out in twenty minutes from a piece of clip art, was literally the first SSTO I have built and flown that wasn't based on a plane. Ever.

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On 8/11/2017 at 1:36 AM, Tex said:

I whipped up a craft in a few minutes as a hypothetical. In fact, I called it the "Hypothetical." I retained the same basic shape with all stock parts, mirroring the shape of the clip art as closely as I could. Came up with this:

 

  Reveal hidden contents

Yqjrd67.png?1

 

Around 2,500 m/s. Not quite enough to get into orbit, but the TWR was extreme so of course I gunned it going straight up with all the orange suits inside.

 

  Reveal hidden contents

eGabUGw.png?1

 

However, I was encouraged by that number. 2,500 m/s of delta-v? Surely I could squeeze it out somewhere. I made a few refinements, higher ISP engine, and used every possible fuel space. I used no part clipping other than to cheat a tiny bit by squeezing two toroidal fuel tanks into the tippity top of the rounded nose cone, as it couldn't store fuel. The top section, right above the hitchhiker capsule, is a C7 brand 2.5-1.5m adapter, because it holds fuel and oxidizer.

  Reveal hidden contents

fyg4hRm.png

 

At this point I was like Holy crap, this might just be possible. It was so tantalizingly close to be  able to make orbit, and while all of these designs had the guts to get into space, none would make orbit.

Then it hit me- fairings. Use a fairing for the upper body, and stuff as many fuel tanks as possible as I could. So I did just that. Yeah, a little cheaty, but the point was to keep the same basic body shape while still having as much fuel in there as possible. I pretended that the fairings were solid pieces that contained fuel tanks. Besides, you can't tell from behind a fairing anyway. Shush.

 

  Reveal hidden contents

vGIt7UN.png

 

Then guess what happened?

It worked. It freakin' worked.

 

  Reveal hidden contents

gbKkYm9.png

  Reveal hidden contents

mycc4dk.png

 

Way, waaaay back a long time ago, I did the K-Prize challenge and got a badge by the skin of my teeth. This vehicle, this thing I hammered out in twenty minutes from a piece of clip art, was literally the first SSTO I have built and flown that wasn't based on a plane. Ever.

Woah, nice job dude.

It would be preferable if you disabled the fairing stage. You know, aerodynamics, heat shielding, overall closer to the actual thing.

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On 8/10/2017 at 6:29 PM, MaverickSawyer said:

Part of the appeal of the "classic" spaceship can be placed upon the shoulders of Heinlein. He used ships of that style for many of his earlier stories... though the transfer ship in "Farmer in the Sky" was refreshingly realistic.

Keep in mind, many of the stories using ships of this design are torchships, aka "silly physics, you have no power here" ships. :wink:

Torchships are perfectly fine so long as your radiators are as hot as the surface of the Sun, if not hotter.

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Well... for one thing, the Vector is kinda OP. Still a nice ship though! 

I think at this point we are assuming that it is all fuel, with a little pod for the humans?

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9 minutes ago, Nibb31 said:

I don't find this very different from the ITS.

Hmmm...

GsyREf7.png

spacex-its-enceladus.jpg?itok=q96TzCon&f

Okay, I can see where you're coming from on that.

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