Idea Space Liner-type ship

[bwog]

It would be a cross between a cruise ship and a space mothership. Who doesn't like the idea of taking tourists on a cruise to Mars? And if there's a virtural cockpit, you should be able to ctrl+arrow into different parts of the cockpit and/or the rest of the ship. It would also be fun to crash it into Brighton Beach and crush all the puny DG's :lol:

If anyone could make something this big that isn't a frame hog, then that would be awesome. But you don't have to of course.

 

[Mojave]

Arrow by Dan Steph. UCGO

 

[StevoPistolero]

This summer I am working on a line of space yachts. Not quite cruise liners, but I could design one as well. I agree: space is for tourism. We need more pleasurecraft.

 

[bwog]

Arrow by Dan Steph. UCGO

That's what I'm using currently as one

 

[Mojave]

That's what I'm using currently as one

oo. ok, it's a good ship though and I really enjoy going to Jupiter with it.

 

[T.Neo]

I have been working on a passenger spacecraft for Orbiter. Not quite a pleasurecraft or a cruise ship, but something that makes sense for transporting passengers- unlike stuffing five people in a DG cabin for two years. The Arrow is a good ship, but IMO its true purpose should be as a spacecraft that can go from LEO to the Martian surface and back again. I'm aiming more for a general craft that can take two Deltagliders and their passengers to multiple destinations throughout the solar system.

I present the Tumbling Passenger Ship Concept:

In orange: central truss, also contains transfer tunnel to the habitation module. I may redesign the spacecraft so that the truss is in tension while under thrust.

In grey: docking node.

In green: propulsion module.

In light blue: radiators. Need to be reworked into a more suitable configuration.

In dark blue: habitation module. Living space for 28 people.

In red: Delta Glider-type spacecraft. Could be DG, XR1 or DGIV, although provision is made for XR2.

Once coasting, the spacecraft spins on the X axis to generate artificial gravity. During acceleration however, "up" becomes "down". Cargo, personal items and other systems must be placed in a manner that will prevent shifting or damage. Passengers lie prone in their rest bunks. Cockpit section is designed to swivel through 90 degrees to function either during cruise or acceleration.

Artificial gravity is around 1 g, generated by spinning the craft at just under 1.9 RPM. Acceleration is around 1-1.2 g.

Maximum service velocity is around 200km/s and Delta V is around 500km/s. This is to facilitate high-velocity low duration brachistochrone trajectories between planets.

EDIT:

A tractor design, with the propulsion system pulling the habitation module and the docking node and the main truss in tension has another advatantage- the direction of gravity during acceleration and rotation is the same. It seems like the more advantageous option.

 

[Bloodworth]

Picies festival liner by Rag Tag Fleet.

 

[T.Neo]

Yes. Or the QE2 equipped with a Dean drive.

 

[Lucy]

That ship of yours would be interesting to dock at while it's rotating about the X-axis...

 

[T.Neo]

Well, docking is not supposed to occur during the cruise phase- it would be spun down during docking in orbit around say, Earth.

But if you spacecraft has a docking port along the center of gravity, docking while spinning should not be too hard. Essentially like docking with Station V in Wo2001.

I'd imagine docking during spin in a DG would be tricky at best, due to the docking port being off center.

 

[Moach]

hey T.Neo! love the concept!

a ship like that was pretty much what i had in mind for a earth-lunar-mars cruiser... it would be supplied by a g42 craft over a few flights at LEO...

then, a couple of landing modules would be attached to it, for reaching the mars/moon surface...

a ship like this would never de-orbit...


now, if you're not gonna dock while spinning, there's no need at all to have a long crew transfer tunnel along the central truss - the dock could be right at the hab module

and i'd go for a "puller" engine setup - allows for a lighter truss and, as you said, keeps the same gravity direction durring accel...

very nice concept - and pretty viable, i hope :thumbup:

 

[T.Neo]

a ship like this would never de-orbit...

No- it isn't built for landing or reentry at all.

But if it had to be disposed of at the end of it's service liftime... :lol:

now, if you're not gonna dock while spinning, there's no need at all to have a long crew transfer tunnel along the central truss - the dock could be right at the hab module

You raise a good point, but there are two reasons for having the docking ports where they are. Firstly it reduces the stress on the docking mechanism (however applicable this is to a docking mechanism made from unobtanium...) and secondly it means that differences in mass and whatnot don't effect the rotation too badly. I suppose it reduces danger from shifted objects in the docked craft too.

There is also a docking port at the end of the hab module, for docking with supply craft or orbital stations.

and i'd go for a "puller" engine setup - allows for a lighter truss and, as you said, keeps the same gravity direction durring accel...

Indeed, but it causes certain problems (although from a very non-engineering perspective). It makes docking a whole lot harder, and messes my meshes around just a bit.

On a plus side, the crew will have a wonderful view of their spacecraft from the cockpit. :hmm:

I am busy meshing another spacecraft concept of mine at the moment, but as soon as I'm finished (or at least acceptably finished) I'll post updates on this "Tumbling Ship Concept".

 

[Moach]

i love the idea of the "tumbling ship"...

when i suggested the dock should be in the hab module, i had in mind that whatever was docked there would not remain so during flight...

but if the plan is to take the DG's along for the ride, then indeed, that's where they should be...

now, for the puller engine setup, i imagined something similar to a star-wars pod-racer... a transversal structure would hold the two engines apart from the fuel tank center... strong cables could fasten the whole thing...
the cables would be fastened around the dock in the middle section...

now, a solution to avoid a long tunnel, is a sort-of elevator... a pressurized pod could travel on internal "rails" along the main truss between the hab and the dock, allowing a much lighter structure - and less danger of hull-breach related problems and whatnot... for safety reasons this system should only be operated when not "tumbling"


have we stolen the thread? :threadjacked::LOL!:

cheerz

 

[T.Neo]

now, for the puller engine setup, i imagined something similar to a star-wars pod-racer... a transversal structure would hold the two engines apart from the fuel tank center... strong cables could fasten the whole thing...
the cables would be fastened around the dock in the middle section...

I'm trying to keep the structure as rigid as possible while still being light (to facilitate spinup/spin down and other manouvers).

The basic concept is a lot like the Avatar ISV Venture Star:

The engines are on either side of the propellant tanks. I'll probably put them on their own trusses to keep them away from the propellant tanks (to reduce heat load on the tanks, and reduce the angle the engines need to be canted out at), and I'll probably have taut cables to prevent them from buckling (under thrust or spin). But they won't run all the way down to the docking node- I'd like to keep the area free for docking.

now, a solution to avoid a long tunnel, is a sort-of elevator... a pressurized pod could travel on internal "rails" along the main truss between the hab and the dock, allowing a much lighter structure - and less danger of hull-breach related problems and whatnot... for safety reasons this system should only be operated when not "tumbling"

I've thought of that too- honestly I'd be more afraid of something going wrong with the elevator. It'd also be limited in the number of people it can carry at one time, whereas people can just float through a tunnel.

The transfer tunnel will have whipple shield (naturally) and will perhaps be compartmentalised (or have the capacity for it). There are also conduits and whatnot that run through the tunnel- it's a tad easier to access them from inside.

have we stolen the thread? :threadjacked::LOL!:

I think so. :shifty: :lol:

 

[Moach]

one thing that comes to mind about a "tumbling ship", is that as fuel grows dim, the CG will shift...

the rcs thrusters would have to be progressively calibrated to compensate for this, in order to induce a g-spin without causing any undesired translation effect, no?

 

[T.Neo]

one thing that comes to mind about a "tumbling ship", is that as fuel grows dim, the CG will shift...

the rcs thrusters would have to be progressively calibrated to compensate for this, in order to induce a g-spin without causing any undesired translation effect, no?

Very good point. The only way to truely rectify this would be to have the propellant tanks located at the axis of the spin, which would mean pumping the fuel all the way to the engines during acceleration (which would be suboptimal).

Perhaps fuel could be transferred into progressively aft tanks to try to reduce this problem? I'm not sure it would help too much. Perhaps counterweights of dense material could be shifted towards the propulsion section before spin-up? These counterweights might be prohibitively massive (or at least impact the mass of the craft negatively enough to be unsuitable).

On the other hand, the small translation effect may not be too problematic. I wonder if the trajectory would be less peturbed at the faster travel times...

 

[Moach]

another possible way of correcting for this, is to have a telescopic truss that allow the engine assembly to "slide forward" as fuel runs out... the centrifuge effect at a greater radius should counteract the mass reduction... would it not? - this would save up on long fuel lines and heavier pumps

of course, the CG could be easily corrected simply by adjusting the thrust on the attitude jets.... but it would be at the cost of some extra RCS propellant - should be worth it tho, considering the mass of a little more RCS fuel vs. that of an extending truss mechanism


in a long trip, even the most minute translation effects could result in a large course deviation... correction would have to occur sooner or later, sooner being better, fuel-wise


anyways, this is only a real problem during spin-up/spin-down and other rotation maneuvers... during the burn time itself, no correction is needed... so it's not like it has to be done constantly...

cheerz

 

[T.Neo]

another possible way of correcting for this, is to have a telescopic truss that allow the engine assembly to "slide forward" as fuel runs out... the centrifuge effect at a greater radius should counteract the mass reduction... would it not? - this would save up on long fuel lines and heavier pumps

I think it'll add in mechanics where it takes away in lines and pumps.

Perhaps shifting mass would be easier with a fluid (perhaps even propellant). It'll need lines and pumps, but it won't have to pump "uphill".

of course, the CG could be easily corrected simply by adjusting the thrust on the attitude jets.... but it would be at the cost of some extra RCS propellant - should be worth it tho, considering the mass of a little more RCS fuel vs. that of an extending truss mechanism

I should be able to have enough RCS fuel, if I have a Dv of 500km/s for the mains.
Shouldn't it be possible though to compensate by reducing the thrust of one set of thrusters?

in a long trip, even the most minute translation effects could result in a large course deviation... correction would have to occur sooner or later, sooner being better, fuel-wise

anyways, this is only a real problem during spin-up/spin-down and other rotation maneuvers... during the burn time itself, no correction is needed... so it's not like it has to be done constantly...

Indeed. My flight times should be pretty short (gets up to about a month for Jupiter). I also have a Dv excess on the order of tens of km/s (not sure why :shifty so the cost of corrections might be bearable.

 

[Izack]

I've been looking for a good tourist/passenger liner for a while now, especially from the Earth to the Moon. I was thinking an A350 or 787 in space. :lol:
I don't think there's much need for artificial gravity on a 3-day Moon trip, and besides, microgravity could be part of the attraction.