200 ton Frontier Trader with Deck Plan

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Jak Nazryth
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Re: 200 ton Frontier Trader with Deck Plan

Postby Jak Nazryth » Mon Mar 06, 2017 8:52 pm

AnotherDilbert wrote:
Mon Mar 06, 2017 6:09 pm
Jak Nazryth wrote: While you bring up a good point in "real" physics, most every Traveller ship designed since 1977 never considered aligning the maneuver drives to coincide with the axis of center of mass. Look at the traditional deck plan for the Suliman class Scout. :)
Most of the classic designs, including the Type S do have drives balanced symmetrically around the centre of the ship?
Image

But of course you do your ships as you like.

Jak Nazryth wrote: It might looked balanced on a flat sheet of paper, but the center of mass can vary dramatically.
Mass isn't a thing in MgT2 for star ships. If you start worrying about the mass of cargo, if its half full or even empty, then what about fuel tanks?
Agreed. Of course fuel tanks should be considered, but it is a very light fluid that can be pumped between tank to trim the balance. In your ship the fuel doesn't mass more than 60 tonnes, while the cargo can potentially mass 1000 tonnes or even more.

Jak Nazryth wrote: Plus, the M-drive and the location of the thruster plates don't have to be located in the same place.
Truster Plates is the M-drive. Thruster Plates is just MT terminology.

Differences aside with how much reality to impose on a Traveller ship... I love this cross section of the type S scout courier. :)
Condottiere
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Re: 200 ton Frontier Trader with Deck Plan

Postby Condottiere » Mon Mar 06, 2017 9:15 pm

Aircraft tend to compensate for prevailing forces acting on it.

Image

Vector thrusting would be an option.
Jak Nazryth
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Re: 200 ton Frontier Trader with Deck Plan

Postby Jak Nazryth » Mon Mar 06, 2017 9:29 pm

great photo! :)
Plus gravic controls would negate the need for vectored thrust as M-Drives are reaction-less... unless Mongoose redefined that as well... ;)
In stead of small clusters of rockets/jets spread out in various locations on the hull as current space craft use, it is probably clusters of smaller thrust/grav plates that control the pitch, yaw, roll, etc...
In essence, you can hover in place any number of meters above the ground silently, or possible a slight hum, perfectly level, with no other effects... other than slowly consuming the fuel for your power plant.
AnotherDilbert
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Re: 200 ton Frontier Trader with Deck Plan

Postby AnotherDilbert » Tue Mar 07, 2017 1:19 pm

Jak Nazryth wrote:
Mon Mar 06, 2017 7:46 pm
WARNING... RANT ABOUT TO BEGIN... THIS IS MORE TONGUE-IN-CHEEK BUT IS STILL A SORE ISSUE FOR ME...

...

You are over thinking the rules and applying current reality/physics on imaginary ships and imaginary technology that can MANIPULATE GRAVITY!
This is a game for fun so we won't be so bored on weekends.
Please stop trying to suck the fun and creativity out of this pretend game.
You play your game.
I play my game.

I'm not trying to destroy your fun, but I will not change my fun to suit you.

If you do not appreciate comments on your designs, just say so.
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Re: 200 ton Frontier Trader with Deck Plan

Postby phavoc » Tue Mar 07, 2017 2:45 pm

Jak Nazryth wrote:
Mon Mar 06, 2017 7:46 pm
WARNING... RANT ABOUT TO BEGIN... THIS IS MORE TONGUE-IN-CHEEK BUT IS STILL A SORE ISSUE FOR ME...
<snip>
Because it can manipulate gravity. Because it can create it's own gravity.
Show me the mathematical equation for that please.
One big problem is that CT started out in the day of printing on paper - so it cost actual $$ to put each and every word on a page. So some things got left out (well, a LOT of things got left out). Over time you started seeing some articles in JTAS that provided more explanations and depth to the game. And, over time, different publishers tried to add to more details. Unfortunately there isn't a consensus on some things among the various sets.

However a few things do seem to ring through the overall Traveller materials. The first is that anti-gravity allows ships, vehicles and even people to counteract gravity, hence the term "anti-gravity". But for the most part they aren't saying they are countering MASS. And as every HS physics class teaches you, mass and weight (mass in gravity well) are two separate things. So manipulating gravity allows you to do lots of neat things in gravity well. But in deep space it's useless because there is no gravity to counteract. You can though still create your own localized gravity field (internal gravity) that allows you to accelerate and not feel the effects of it in your ship.

That doesn't really address the issue of drives and alignment along the center mass of your vessel. But pretty much every design has the drives oriented along the axis of the ship. And without any sort of details to otherwise disabuse us, I have always assumed that the laws of physics are still being observed. So if you put that drive unit off-axis you'd not be able to control your movement as you chose. Or, in other terms, your anti-gravity capabilities do not generate a field around your vessel that would allow you to ignore how thrust works.

This IS science FICTION, so anything is possible. I just don't see the game mechanics operating differently than they are portrayed.
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Re: 200 ton Frontier Trader with Deck Plan

Postby Condottiere » Tue Mar 07, 2017 5:14 pm

Depends on whether the manoeuvre drive creates a field effect.

I don't think so, but it could be optional at the expense of diminishing of thrust.
Jak Nazryth
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Re: 200 ton Frontier Trader with Deck Plan

Postby Jak Nazryth » Tue Mar 07, 2017 5:54 pm

Since I had two majors in college, physics and Architecture, I'm well versed in the matter. Not the best, but well versed. In fact my first problem the first day of class as a physics major was to take an image of a star, calculate it's distance from us, calculate the speed it was receding from us, calculate when the universe was created, it's half life, and when it would end. This was 1987 when most of us still believed the universe would eventually stop expanding and eventually collapse in on itself again.
My calculations were off by about 2 billion years. Go figure, I wasn't the best physics major.

The drives are not off axis. The are dead center. 95% of the thrust (if not more) is from the engine mass located on the center deck. Dead center of the axial mass. Right behind the power plant. NOBODY made a fuss when they saw the deck plan. Nobody has seen the rest of the elevations or sections. You are taking my longitudinal study section too literally. This is a study section, so that I can study the design, to make sure everything aligns and makes sense functionally and spatially. It is not the final section, it may cause me to change the deck plan if something doesn't make sense.
I don't care about the mass of cargo. Mass is not part of the ship building rules. If Mongoose adds mass to ship building rules, then every single design since 1977 is subject to tumble. Just because drives look centered on a flat piece of paper does not mean they are centered in the ship.
In stead of small thrusters/chemical rockets located in the nose of a ship, and various other places, used to adjust yaw, pitch, and roll, compensating for mass of various cargo, or fuel, or any other eccentric force, a ship that can manipulative gravity and create it's own gravity can adjust it's nose/heading with gravic technology. I tend to think of it as a very advanced gyroscope, but there are no moving parts. The gravic systems can tweak here and there, creating a small gravitational push/pull many times per second to keep the ship stable and level.
If gravity doesn't exist in deep space, why doesn't the galaxy fly apart?
Some of you, you can keep designing spread sheet starships.
I'll design functional, creative, interesting forms and spaces to the best of my ability for enjoyment of role players, while keeping the designs as believable as possible and to stay within the game mechanics and rules to what ever version of Traveller I'm designing them in.

And I DO welcome comments, all comments. I have modified my design twice based on comments and suggestions. But I'm not going to keep silent when very, VERY, intelligent people appear to loose perspective that this is a science fiction role-playing game set in the Far Future invented by Mark Miller in the mid 70's. And a game that uses technology that our current understanding of physics tells us CANNOT happen. Again, show the equation how a 100 dton ship can enter jump space and I'll show you the equation how small grav plates distributed in various places on the hull of ship can overcome eccentric forces so it won't tumble in deep space.

Let me be clear, because the typed word can be misleading. I am not angry or annoyed at anyone. I'm enjoying this debate with a little bit of humor. Because I have seen very smart people on various forums over the last 20+ years go to the mat, and have huge arguments with shouting, insults, name calling, questioning the IQ and understanding, or lack of, basic principals of physics and material compositions, all because they disagreed on "How thick is a traveller ships hull". No shat, that argument happened much to the delight of others on the boards. COTI,,, some time in the late 90's


I'll keep posting my designs, I'll try my best to keep make them reasonable, and flexible, and economical, and interesting, and keep the maneuver drives centered... ;)
I appreciate any and all comments, even ones I don't necessarily like or agree with, because all comments make me think and sometimes rethink my design process.
I'm an Architect, that's what I do.


Keep perspective, keep playing Traveller. :)

Cheers. :)
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Re: 200 ton Frontier Trader with Deck Plan

Postby phavoc » Tue Mar 07, 2017 6:52 pm

Since there is nothing to the contrary either way, it's just as feasible and reasonable to assume that a starship DOES, in fact, use thrusters to adjust roll/pitch/yaw. Gyroscopes are certainly a possibility (we used them today in some spaceborne equipment), but I've never seen them mentioned or drawn on a deckplan.

From everything I've read about gravitic technology in the game system, it requires a gravity field to oppose. So gravitic 'thrusters' would not work away from a planetary gravity field. Someone (DGP?) put out, in one of their vehicle supplements basically a family 'sedan' that could travel between planets. But that was later withdrawn because it didn't fit within the accepted uses of gravitic vehicles.

Ships that land on planets don't use thrusters for lift, but they do require their main engines to actually maneuver - though it's possible they could vertically ascend to orbit using just gravitics.

GURPS Traveller was the only one that put mass into the equation, other versions simply concentrated on Dtons.

To be fair, there is gravity in deep space - but very weak gravity. Gravitics have been presented as only working in strong gravity, and low planetary orbit is about as 'high' a ship can go and still use it's gravitics. Further out the gravity field is just too weak for them to function effectively (and usefully).
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Re: 200 ton Frontier Trader with Deck Plan

Postby AnotherDilbert » Tue Mar 07, 2017 7:21 pm

Jak Nazryth wrote:
Mon Mar 06, 2017 8:52 pm
AnotherDilbert wrote:
Mon Mar 06, 2017 6:09 pm
Image
I love this cross section of the type S scout courier. :)
It's a model made by AdrianH:
AdrianH wrote:
Wed Sep 15, 2010 7:55 am
The ship:
http://www.macs.hw.ac.uk/~adrian/miscpi ... _small.jpg

With the top removed so 15mm miniatures can go aboard:
http://www.macs.hw.ac.uk/~adrian/miscpi ... _small.jpg

View through the aft airlock into the engine room:
http://www.macs.hw.ac.uk/~adrian/miscpi ... _small.jpg
Last edited by AnotherDilbert on Tue Mar 07, 2017 7:39 pm, edited 1 time in total.
AnotherDilbert
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Re: 200 ton Frontier Trader with Deck Plan

Postby AnotherDilbert » Tue Mar 07, 2017 7:29 pm

phavoc wrote: Since there is nothing to the contrary either way, it's just as feasible and reasonable to assume that a starship DOES, in fact, use thrusters to adjust roll/pitch/yaw. Gyroscopes are certainly a possibility (we used them today in some spaceborne equipment), but I've never seen them mentioned or drawn on a deckplan.
The SSOM says gyros.

phavoc wrote: From everything I've read about gravitic technology in the game system, it requires a gravity field to oppose. So gravitic 'thrusters' would not work away from a planetary gravity field.
Anti-grav ≠ M-drive.

Anti-grav as in grav vehicles only work in a strong gravity field.

Thruster plates = Manoeuvre drives works in deep space.

At least in MT, I think I have heard that T5 has changed that?
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Re: 200 ton Frontier Trader with Deck Plan

Postby Jak Nazryth » Tue Mar 07, 2017 7:42 pm

phavoc wrote:
Tue Mar 07, 2017 6:52 pm
Since there is nothing to the contrary either way, it's just as feasible and reasonable to assume that a starship DOES, in fact, use thrusters to adjust roll/pitch/yaw. Gyroscopes are certainly a possibility (we used them today in some spaceborne equipment), but I've never seen them mentioned or drawn on a deckplan.

From everything I've read about gravitic technology in the game system, it requires a gravity field to oppose. So gravitic 'thrusters' would not work away from a planetary gravity field. Someone (DGP?) put out, in one of their vehicle supplements basically a family 'sedan' that could travel between planets. But that was later withdrawn because it didn't fit within the accepted uses of gravitic vehicles.

Ships that land on planets don't use thrusters for lift, but they do require their main engines to actually maneuver - though it's possible they could vertically ascend to orbit using just gravitics.

GURPS Traveller was the only one that put mass into the equation, other versions simply concentrated on Dtons.

To be fair, there is gravity in deep space - but very weak gravity. Gravitics have been presented as only working in strong gravity, and low planetary orbit is about as 'high' a ship can go and still use it's gravitics. Further out the gravity field is just too weak for them to function effectively (and usefully).
You know I think I brought this up on COTI in the late 90's or early "0"s... and I cant remember where I saw it... GURPS, T20, maybe even MT, or maybe even on Freelance, but at one time I could have sworn that I saw a 1000 diameter rule where thrusterless/gravic drives would stop working because of the weakness of gravity. In fact, it got me so worried (as a gamer/dm/designer) that I started incorporating both gravic AND reaction drives on ships. But if that is true, what happens when a ship exits jump space in the outer solar system? Can it even start moving towards the core planets? In any case when I brought it up, nobody could find the rule. As for myself, since its "sci-fi game" technology, I just say "it works". All these questions and speculations are awesome thought experiments, but in the end, the game mechanics are the game mechanics.
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Re: 200 ton Frontier Trader with Deck Plan

Postby phavoc » Tue Mar 07, 2017 9:38 pm

AnotherDilbert wrote:
Tue Mar 07, 2017 7:29 pm
The SSOM says gyros.
I stand corrected. SSOM did say gyros:

Not quite. From "Starship Operator's Manual, p.3: "The orientation subsystem enables the ship to control its direction of flight and orientation attitude. With the advent of superdense composite materials at higher tech levels, inertial gyroscopic systems for reorientation the ship become practical. Housed at the starship's center of mass, these units are fitted in an assembly kept in near-vacuum and revolve at speeds approaching one million RPM. The tremendous inertial force generated from the device actually allows the starship to 'push itself off' the flywheel by means of a surrounding sphere of focused grav modules. Thus, the ship actualy rotates about that gyro when changing orientation."

This is but a tiny part of the description of the thruster plate drive system, addressed in length in that book. I strongly recommend getting it for any Traveller player interested in the workings of starships in the 3I.

This from a MGT thread - viewtopic.php?t=119347&start=20

My only issue with that is that the gyroscope would have to be very tiny to not show up on any drawings.

I also wonder how well gyro's would work in atmosphere/gravity well?
AnotherDilbert wrote:
Tue Mar 07, 2017 7:29 pm
Anti-grav ≠ M-drive.

Anti-grav as in grav vehicles only work in a strong gravity field.

Thruster plates = Manoeuvre drives works in deep space.

At least in MT, I think I have heard that T5 has changed that?
Not sure about T5, I know it's got a number of different technologies included in it.

Aren't thruster plates, as described at least, limited to MT? I don't have any of my references available to compare.
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Re: 200 ton Frontier Trader with Deck Plan

Postby phavoc » Tue Mar 07, 2017 9:43 pm

Jak Nazryth wrote:
Tue Mar 07, 2017 7:42 pm
You know I think I brought this up on COTI in the late 90's or early "0"s... and I cant remember where I saw it... GURPS, T20, maybe even MT, or maybe even on Freelance, but at one time I could have sworn that I saw a 1000 diameter rule where thrusterless/gravic drives would stop working because of the weakness of gravity. In fact, it got me so worried (as a gamer/dm/designer) that I started incorporating both gravic AND reaction drives on ships. But if that is true, what happens when a ship exits jump space in the outer solar system? Can it even start moving towards the core planets? In any case when I brought it up, nobody could find the rule. As for myself, since its "sci-fi game" technology, I just say "it works". All these questions and speculations are awesome thought experiments, but in the end, the game mechanics are the game mechanics.
M-drives (whatever their magical tech is) have to work outside of a gravity well to move between planets. You could never carry enough reaction mass for standard reaction drives to work. Plus the amount of energy that your reaction drives would have to derive from their fuel.. well, I've never thought the reaction drives should be used in larger vessels, but that's water under the bridge at the moment.

One would think that a revised SSOM/Engineering supplement would find a nice market. You are right, these questions have been around for quite some time.
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Re: 200 ton Frontier Trader with Deck Plan

Postby AnotherDilbert » Tue Mar 07, 2017 10:39 pm

Some quotes from MT:
The second major breakthrough is artificial gravity. ... Because of its nature, artificial gravity is not a very efficient means of locomotion in deep space where there are no strong gravity wells to push against.
The fourth significant development came from the search for a starship maneuver drive that did not lose efficiency when away from a strong gravity well. Artificial gravity and damper technology led to yet another sub-atomic force-based technology. This new, artificially generated force pushes against a vessel's "thrust plates" themselves, which make true reactionless thrusters a reality for starship-sized vessels.
MT Referee's Manual, p56.


I'm not exactly a fan of gyros revving millions of rpm inside a spacecraft, but that is what SSOM specifies. If one would ever malfunction it would tear the craft apart with the released kinetic energy.
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Re: 200 ton Frontier Trader with Deck Plan

Postby Condottiere » Wed Mar 08, 2017 7:44 am

Considering that mongeese square off against cobras, you wouldn't think they'd be deliberately ambiguous.
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Re: 200 ton Frontier Trader with Deck Plan

Postby steve98052 » Thu Mar 09, 2017 3:50 pm

It does seem to be pretty much customary to put maneuver drives along the center of a deck's central axis, without worrying about whether it's anywhere near the vertical center. Maybe the internal artificial gravity takes care of thrust asymmetry relative to the decks' "up" and "down", but not relative to starboard and port.

I seem to remember reading somewhere that gravity control is also used to maintain structural integrity of very large ships under high acceleration.

Of course the general answer to all of these problems is that the physics of science fiction gravity control are not fully spelled out, but that's not fun in-game.

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