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ravells
07-25-2008, 06:31 AM
This is the WIP of a map request here (http://www.cartographersguild.com/showthread.php?p=27592#post27592) from Guild Member 'someguy' for deckplans of a custom built broadsword class starship.

Two very helpful references have been provided. The first is side elevation of the ship from Andrew Boulton's website (http://www.traveller3d.com/sizechart/index.htm) (Thanks Andrew!) which is set against a grid, so calculating the dimensions of the ship is straightforward.

The second reference is a spreadsheet provided by Someguy with the ship's specifications.

I plan to draw the deckplans in Serif Drawplus, a vector drawing package.

The first step is establishing the dimensions as below.

ravells
07-25-2008, 08:40 AM
The next step (I guess) I to look at the spreadsheet and get a general idea of what the components of the ship are and how big they are. I've taken the main components in the spreadsheet whose size is indicated in Displacement tons (setting the biggest component, armour, to zero as everything else is inside the armoured superstructure). I then expressed each component as a percentage of the total which would allow me to eyeball roughly how much room each component takes up. This is what I came up with.

Steel General
07-25-2008, 09:03 AM
I'm admittedly not into the Sci-FI as much as fantasy, but it's looking good so far.

Though it does remind me of one of the drop-ships from Battletech

ravells
07-25-2008, 09:11 AM
We were having exactly that discussion on the map request thread!

RobA
07-25-2008, 09:41 AM
What, may I ask, is a "displacement ton (tonne?)"

A measurement of mass, or a measurement of volume?

-Rob A>

ravells
07-25-2008, 09:43 AM
Good question.

In Traveller, a "ton" of starship size is defined as 14 cubic meters, the volume of a ton (1000kg) of liquid hydrogen. Taken from here. (http://www.freelancetraveller.com/features/shipyard/tonnage.html)

Just looking at the design of the ship, it looks like when it's in a planet's atmosphere and the gravity pull is significant it can only really travel up or down (give or take a little lateral movement with retros) given the location of the thrusters. If it tried to fly horizontally, everything would slide down the decks and make an awful mess!

RobA
07-25-2008, 11:28 AM
OK - thanks. So you calculated the volume of each deck based on its position in the sphere and the table provided? Cool (anal, but still cool).

BTW, what font was used?

-Rob A>

ravells
07-25-2008, 11:36 AM
You think that's anal? You should see what the gearheads on the Traveller boards do...

The font is called 'Fanboy Hardcore' from Blambot. I was looking for a 'graphite light' type font which I'm sure I had once upon a time, but I lost it :(

I found a nice frame! (no further with the actual drawing though), too busy messing with my avatar...oh look a shiny thing!

Valarian
07-25-2008, 11:37 AM
Just looking at the design of the ship, it looks like when it's in a planet's atmosphere and the gravity pull is significant it can only really travel up or down (give or take a little lateral movement with retros) given the location of the thrusters. If it tried to fly horizontally, everything would slide down the decks and make an awful mess!
If the ship were reliant on reaction thrusters (like in BattleTech) this would be correct. With reaction drives, you'd also only get gravity when in space while the ship was under acceleration. In Traveller, there's the handwavium of the grav plating on the decks to avoid this. Traveller manoeuvre drives generate artificial gravity.

ravells
07-25-2008, 12:01 PM
Cheers Ian, I sort of vaguely knew that but how does the artificial gravity work when there's real gravity as well? e.g. if you are hovering 500 feet over a large planet. Presumably the handwavium cancels out effects of external gravity?

Valarian
07-25-2008, 01:46 PM
From TL9, Traveller uses gravitic drives. Handwavium states they use gravity in maneuvering the ship. I could give a nice long explanation about vectors and cancellation of local gravitational fields, but I tend to save it for the players. :D

Basically, inside a planet's gravity well, the drive would be using the planet's gravity to maneuver. Outside, it would use the general field of the solar system. It does have implications for maneuvering the ship should you misjump and find yourself outside a solar system.

someguy
07-25-2008, 04:49 PM
All i can ad to this line of thinking is the comment made in Firefly about the "tilt" one feels as you leave space and "Mother nature take over".

And the side slice looks great.

Do the Modular cutters come out the side? or are the jutting up though like in Andrews depictions?

ravells
07-29-2008, 03:11 PM
I don't think that modular cutters are going to fit....see the pic below which is to scale. I think the problem is that although the cutter is only 50 dt in volume and the cruiser 800 odd dt, volume grows geometrically with dimensions. Add to that the the cruiser is a sphere (best surface area to volume ratio) and the cutter a cigar shape (not as good) and you end up with this...unless I've seriously miscalculated. I think the best you will be able to do is a ship's boat or two at a stretch.

The volume of a sphere is 4/3 * pi *r^3.

The radius of the sphere is about 17m = circa 20,500 m^3 which divide by 14 (14 m^3 = 1 dt) = 1464 dt. which is nowhere near the 600 dt - oh heck!

I've posted on the COTI board for help!

ravells
07-29-2008, 04:47 PM
I went to the COTI board for help and Dan 'Far Trader' Burns referred me to Brooke's deckplans (http://www.sff.net/people/kitsune/Traveller/bsimages/index.html), which are simply beautiful. Dan agrees that the radius of the sphere should be around 13.5m to get a volume of 800 dt.

I feel totally unworthy .... would you like to use Brooke's deck plans instead?

mathuwm
07-29-2008, 05:59 PM
Yours are cooler

Brookes looks like they were made in Microsoft word


Although with a good amount of info

And doesn’t traveler predate battletech

someguy
07-29-2008, 08:31 PM
I went to the COTI board for help and Dan 'Far Trader' Burns referred me to Brooke's deckplans, which are simply beautiful.

I already linked to them in a previous post. I have taken the time to look at the materials you have posted and I find all of it to be excellently done.


Dan agrees that the radius of the sphere should be around 13.5m to get a volume of 800 dt.

That is actually faulty thinking. Dan's mistake is that he isn't thing in proportions. This design is not one ship, it is three ships. One ship is 700 dTons, the two others are 50 dtons each.

Imagine a sphere of water. Its volume is 14 ounces (representing the 700 dTons of the main ship). Now you place two one ounce (representing the 50 dTon cutters) cylindrical glass objects into the sphere of water.

The sphere of water is displaced by the introduction of the two glass cylinders.

I will check with some of my math buddies are "Reed College" and see what numbers they come up with.


I feel totally unworthy ....

Rubbish. Absolute Rubbish!

someguy
07-29-2008, 09:21 PM
OK, after talking With Will, he came up with this.

1 dTon is 14 m^3, so a volume of 10990 m^3 and a radius of 13.8 m.

This assumes:

The main ship is 700 dTons, with two 42.5 dTon cylinders within the hull.

Only 85% of the cutters are with in the ships hull. the other 7.5 dTons are outside the hull.

This has an end hull dtons of 800. (700+(42.5*2)+(7.5*2) = 800.

But anyway, I don't need exact, just close.

ravells
07-30-2008, 05:14 AM
Gotcha. I'll rework the design.

Cheers and thanks for the compliments!

Ravi

ravells
08-01-2008, 02:19 AM
So something more along these lines then?

Steel General
08-01-2008, 08:18 AM
Those are looking pretty durn good...

ravells
08-01-2008, 08:54 AM
Cheers SG, but they're really just quick and dirty models. I'm trying to get a feel for relative sizes of the objects.

someguy
08-01-2008, 09:26 AM
So something more along these lines then?

Hmm. I was doing some fiddling around and I was thinking that this version didn't need the Cutters at all.

Rather it could have a drop ship that's a saucer shaped that attaches to the underbelly of the ship.

I attached the work sheet of the new design. Hopefully this one is easier to draw.

Steel General
08-01-2008, 10:13 AM
Cheers SG, but they're really just quick and dirty models. I'm trying to get a feel for relative sizes of the objects.

Hey, ya gotta start somewhere, and I don't have the patience to do 3D modeling. :D

ravells
08-01-2008, 03:53 PM
Hmm. I was doing some fiddling around and I was thinking that this version didn't need the Cutters at all.

Rather it could have a drop ship that's a saucer shaped that attaches to the underbelly of the ship.

I attached the work sheet of the new design. Hopefully this one is easier to draw.

Hey stop changing them!! :)

Have to change the position of the main thrusters unless you want hole in your saucer (plumbers hissed intake of breath) going to cost you a few mega credits that will, mate!

I'll get onto it soon and hopefully more time next week to seriously spend in putting something decent together.

Ravs

someguy
08-01-2008, 06:09 PM
Hey stop changing them!! :)
It was just a suggestion...

Have to change the position of the main thrusters unless you want hole in your saucer (plumbers hissed intake of breath) going to cost you a few mega credits that will, mate!
Here is a very crude illustration of what I though was the maneuver drive setup.

ravells
08-02-2008, 05:29 AM
That's a possibility, but the drives are now in the 'legs' which previously allowed access to the ship. I'm also wondering whether it would be credible to have the engine ports making direct contract with the ground (only because I haven't seen it before).

I really do like your new idea though (I was joking about the changes!) and far prefer working with something original than one that has already been drawn (usually much better) by others.

How about mounting 4 thrusters in between the legs? (errrrr so to speak)

Quick mock-up below. With an extra copy of the saucer placed away from the main ship.

waldronate
08-02-2008, 04:39 PM
It might also be doable to make the saucer into the top segment of the sphere.

someguy
08-02-2008, 07:55 PM
That's a possibility, but the drives are now in the 'legs' which previously allowed access to the ship. I'm also wondering whether it would be credible to have the engine ports making direct contract with the ground (only because I haven't seen it before).
What I was thinking was that the elevator was between the engines. But I also like your idea too, it makes the ship look less like the standard Broad sword.

I was thinking of calling this an "Ares" class Merc Cruiser.

I really do like your new idea though (I was joking about the changes!) and far prefer working with something original than one that has already been drawn (usually much better) by others.
No worries, that how I took it.

How about mounting 4 thrusters in between the legs? (errrrr so to speak)
Quick mock-up below. With an extra copy of the saucer placed away from the main ship.
One possibility is to do away with the legs and make them restartable landing struts. Or would that be too much like the battletech ship?

It might also be doable to make the saucer into the top segment of the sphere.
Now thats a good Idea. The lander has the same AR (Armor rating) as the main ship. It would keep it out of the way of the main thrusters. However, it would have to complete the sphere rather than just attach to the outer hull; otherwise it would downgrade the hull to Unstreamlined.
All the vehicle bays would have to be up top otherwise they couldn't transfer to the drop ship.

ravells
08-02-2008, 08:26 PM
I'll get on it. I like the retractable landing struts too.

waldronate
08-03-2008, 12:23 AM
One possibility is to do away with the legs and make them restartable landing struts. Or would that be too much like the battletech ship?

Now thats a good Idea. The lander has the same AR (Armor rating) as the main ship. It would keep it out of the way of the main thrusters. However, it would have to complete the sphere rather than just attach to the outer hull; otherwise it would downgrade the hull to Unstreamlined.
All the vehicle bays would have to be up top otherwise they couldn't transfer to the drop ship.

Right, the idea was to have a "crater" in the top where the ship would sit. The smaller ship could function as the bridge for the larger or could just be dead weight.

One other thing that's an option with the older concept of cylindrical drop ships is to use the manueuver drives of them as aux drives for the main ship.

ravells
08-03-2008, 05:30 AM
Ships quite often had two bridges, didn't they? The main bridge and (I think) the other one was called the 'battle bridge' or similar if the main bridge was damaged. I think the Enterprise in Star Trek had an arrangement like this as the main saucer bit could detach from the rest.

From a practical point of view - I guess the main bridge would be within the cruiser and the battlebridge would serve as the main bridge for the saucer as well as the battlebridge for the cruiser (while connected).

ravells
08-03-2008, 06:29 AM
So something like this? Sorry about the spindly legs but I just used parts of a desklamp I modelled a while back. The bottom of the main compartment could act as an elevator for access to the ship.

someguy
08-03-2008, 09:50 AM
So something like this? Sorry about the spindly legs but I just used parts of a desklamp I modelled a while back. The bottom of the main compartment could act as an elevator for access to the ship.

Ya know with the legs like that It remind me of the robot in the movie "Space Camp". :)

As for the Saucer section, A little more UFO, a little less Umbrella. :D

I'm Liking the lander being the top of the sphere, but its maneuver drive just doesn't look right to me. Although it enters atmo Top down, the armor acts as the heat shield, it flips over and lands belly down.

ravells
08-03-2008, 05:23 PM
I like your saucer much better...consider it done! If we're agreed I'll progress to the deckplans then?

someguy
08-03-2008, 09:16 PM
I like your saucer much better...consider it done! If we're agreed I'll progress to the deckplans then?

I believe we have the general layout isuess resolved. So, yes.

Turgenev
08-04-2008, 02:27 PM
Even though I really have nothing to add, I just wanted to say that I've been enjoying this thread immensely. Keep up the great work.

someguy
08-04-2008, 07:08 PM
Even though I really have nothing to add, I just wanted to say that I've been enjoying this thread immensely. Keep up the great work.

Cool!:D

You play TRAVELLER?!

Turgenev
08-04-2008, 10:06 PM
Cool!:D

You play TRAVELLER?!

Alas, no but I always wanted to. I do have some Traveller books kicking around but never got a chance to play. The ship design also reminded me of the book, SPACE VIKING by H Beam Piper, so it gets extra credits of cool from me for that connection. ;)

someguy
08-05-2008, 06:27 PM
Alas, no but I always wanted to. I do have some Traveller books kicking around but never got a chance to play. The ship design also reminded me of the book, SPACE VIKING by H Beam Piper, so it gets extra credits of cool from me for that connection. ;)

Ya, I remember those ships, the Enterprise and Nemeses. I guess the "Pan-Galactic Spaceball of Death" goes back farther than even Battletech then.

waldronate
08-05-2008, 07:34 PM
"The Skylark of Space" had a big spacegoing golfball back in 1928. Successive books eventually made it to planetary-scale balls.

http://www.gutenberg.org/etext/20869 if you've never read it.

someguy
08-05-2008, 08:14 PM
"The Skylark of Space" had a big spacegoing golfball back in 1928. Successive books eventually made it to planetary-scale balls.

http://www.gutenberg.org/etext/20869 if you've never read it.

Cool, I may have to put up a bibliography of Spherical ships on my sight once its up and running.

ravells
08-06-2008, 07:04 PM
Here's the latest cross section...I'll play with it some more and then go to the deck plans.

someguy
08-07-2008, 07:08 AM
Looks good. I look forward to see more.

The Good Doctor
12-01-2008, 05:54 PM
I loved the concept of Traveller. We tried it for a short while, but there was a valid critique, in that if you stayed in whatever service to get good at something, when you retired you were OLD. It was hard for us when were 18-20 somethings to relate to being 50 or 60. Now, of course, is it SO much easier.

I think I recall this style of ship from one of the supplements...? I have them, but they're all packed in storage. If I remember, I'll pull them out. Azanti High Lightning, Invasion Earth, and Imperium (loved that game). Always won at Imperium. The owner, in a fit of pique, gave me that game and refused to play anymore. I tried to give it back, but he refused, so I got a couple of cool board games, and several supplements many many years ago. Snapshot was another cool, short game (used for close combat), and I used a lot of those rules when doing DnD when magic and tech intermixed.

Nice artwork. What programs are you using for the artwork, Ravells?

ravells
12-02-2008, 05:32 AM
For these I use a vector drawing program called Serif Drawplus. It has most of the functionality of Adobe Illustrator but at a fraction of the price and it's much more (to me) intuitive to use as well.
best
ravs