Spaceship Design: What makes sense, and what's nonsense?

[WingedKagouti]

Originally Posted by FenrisLoki

So realism is not really a strong point of Star Wars or Star Trek designs. Those are mostly aesthetic. Swoopy closed shapes are fine, but unless your FTL system has a fluid "drag" in its hypothetical physics, there's no real reason for it. People may decide to build that way, but it isn't a necessity.

It's worth noting that most Star Wars spaceships are (in-universe) intended to operate in many types of atmosphere as well as in (hyper)space. Of course, the actual designs are influenced far more by "will it look cool on screen" and "will the toy sell" than any actual workable real world engineering considerations.

[FF_Ninja]

Originally Posted by WingedKagouti

It's worth noting that most Star Wars spaceships are (in-universe) intended to operate in many types of atmosphere as well as in (hyper)space. Of course, the actual designs are influenced far more by "will it look cool on screen" and "will the toy sell" than any actual workable real world engineering considerations.

I believe George Lucas is quoted as something like "I want cars in space."

[FenrisLoki]

Originally Posted by FF_Ninja

I believe George Lucas is quoted as something like "I want cars in space."

I wouldn't doubt something like that. But Star Wars is essentially World War 2 with a skin of higher tech. Computing power is laughable, there is no internet, communications is difficult, and the fighters act just like airplanes in space.

[Fred Brackin]

There are some highly detailed level questions about shape for cross-sectional area and fields of fire for skin-mounted weapone (i.e. turrets).

For those factors the imperial Star Destroyer's "spearhead design" isn't a bad one. It minimizes frontal cross-sectional area while allowing all (or almost all) guns to fire directly forward. When you can't face your target head on having a thinner side (edge on) allows you to reduce area while still allowing at least half the guns to bear.

Of course all of this is "except for the superstructure". ISD's have that honking big superstructure sticking up from the back part of the hull because WWII and modern carriers do.

Oh, and the hull is covered by engineering nooks and crannies because some people really groove on detail. If stealth against active sensors was a factor the hull would be as smooth as you could make it. To make targeting critical areas under the skin as difficult as possible too.

[ericthered]

Bilateral symmetry makes sense for a certain kind of warship: one in which you are typically accelerating orthogonality to the direction of the enemy... or in other words, where dodging is more important than closing the distance. You have a powerful engine that moves you "up", but you fire "forward". To change the direction you dodge the ship rolls left or right. To minimize the profile and make your spinning more efficient you end up with a long thin rod with the main engine mounted at the midpoint of the rod... at least as far as weight goes.



The job of the ship and the surrounding technology will determine a lot about the ship. Some things to watch for:

• Does it enter the atmosphere? If so, you want it streamlined, and long and thin also helps.
• Does it move at high relative speeds through space? it might need shielding, and the most efficient way to shield is to make a long skinny ship with heavy shielding at the front.
• Does it experience high acceleration, and does it experience it from more than one direction? Many "realistic" designs have large solar or magnetic sails towing a body at a slow speed, and are loosely put together, while a ship that is made to take serious thrust in one direction tends to be shaped like a rocket.
• What's providing power, and how do you shield it? some spacial and material separation between the humans and the reactor is often a good idea.

some idea of what your spaceship paradigm is would help here as well.

[RyanW]

Originally Posted by WingedKagouti

It's worth noting that most Star Wars spaceships are (in-universe) intended to operate in many types of atmosphere as well as in (hyper)space. Of course, the actual designs are influenced far more by "will it look cool on screen" and "will the toy sell" than any actual workable real world engineering considerations.

And (especially early on) "can we build it using readily available model kits?" The main ships use off-the-shelf model kits for most of their detail parts. There are background ships that are not much more than an airplane model with the wings cut off and bits slapped on to make the outline less recognizable.

[Pomphis]

Originally Posted by FF_Ninja

My plan is to design an entire hierarchy of new ships for futuristic Earth, starting from the earliest space-fairing vessels, gradually incorporating FTL into the design (haven't settled on what FTL actually looks like in this setting), and building on that form factor over time.

As others have said, almost everything depends on the technology.

Do you have artificial gravity? Do you use spin gravity?

Do you have reactionless drives?

Are the FTL drives huge or small? Do they need huge amounts of fuel, as in Traveller?

Do you have force fields? If yes, can they have any shape or only some?

With enough superscience I prefer globe and egg shaped ships - simple, structurally sound, good surface/volume ratio.

[Varyon]

An interesting consideration when it comes to gravity is for spacecraft that are meant to operate planetside as well as in space. Planetside, a layout like a modern airplane (long and short) makes sense, whereas in space, a layout like a tall tower (tall and skinny) makes sense, provided constant - or at least frequent - thrust. The Savage Chicken from the webcomic Freefall has an interesting compromise - many of the amenities rotate or are otherwise setup to work under either situation. For example, the tables have booth-style seating, and the seats are setup so that the seat and back are functionally interchangeable, while the table can rotate for either orientation. That example can be see here.

Another consideration - the bridge being located at the front of the ship, with a big transparent "window" to see out of. That's fine for a "spaceship" that's going to spend most of its time flying around planetside (such as for The Savage Chicken), but realistically the bridge being further in, and relying on the ship's sensors, makes a lot more sense (using Spaceships, a Control Room in one of the Core sections is going to be much more well-protected than one elsewhere, although I think ejecting your Control Room in an emergency isn't available if you do that). Things in space are, quite frankly, too far away for the human eye to be of any use - and given the velocities necessary to get anywhere, by they time you can see something, it's too late for you to do anything about it. Best to avoid a big honking weakspot (transparent materials are unlikely to be as resilient as opaque ones) that doesn't even accomplish anything for you. Luxury spacecraft and the like, however, may well have direct viewports, for those wanting to see space with their own eyes rather than through a camera.

[Fred Brackin]

Originally Posted by Varyon

A Things in space are, quite frankly, too far away for the human eye to be of any use - .

The ship's instruments should do it better but you have to factor in brightness against distance. Stars are far away but still visible.

I once saw the calculation that one of Transhuman Space's fusion pulse drives with about 30 GW of output leaving Mars orbit could be seen with the naked eye from Earth orbit.

You'd still want the computer to tell you exactly how far away it was and how fast it was going but in some universes early detection with the human eye isn't that unreasonable.

[Frost]

Originally Posted by Fred Brackin

The ship's instruments should do it better but you have to factor in brightness against distance. Stars are far away but still visible.

I once saw the calculation that one of Transhuman Space's fusion pulse drives with about 30 GW of output leaving Mars orbit could be seen with the naked eye from Earth orbit.

You'd still want the computer to tell you exactly how far away it was and how fast it was going but in some universes early detection with the human eye isn't that unreasonable.

Even if early detection and navigation by direct observation are not practical I would still expect most long range ships to have a viewing port of some description (although probably only one) mostly for morale reasons.

While most of the time there is nothing to see I think there is a psychological case for actually being able to see outside without any sort of mediation.

At a guess these ports would be located as far as possible from the most vital parts of the habitat and heavily shuttered rather than the classic picture window on the flight deck.