The great conversion of MegaTraveller starships back to High Guard

[Sigtrygg]

The same thing happens in a hovercraft, it is nothing to do with pushing against the road. or aircraft, or real world rocket, in space.

You have a momentum vector, it's how motorcycles do the wall of death.

 

[collins355]

I got very confused reading this thread, because in TNE/FF&S "HBT" stands for High Bypass Turbofans. Clearly not the usage here!

 

[AnotherDilbert]

I got very confused reading this thread, because in TNE/FF&S "HBT" stands for High Bypass Turbofans. Clearly not the usage here!

Sorry, in MgT it means High Burn Thrusters, basically a big rocket you strap to your ship.

 

[Condottiere]

They made HBT rather limited, you can only add a G or two.

Originally HBTs were a retrofit (MgT1), not a part of the regular drive system, it's still listed in the Spacecraft options chapter, not the Drives chapter. In that context it makes sense that it is not covered by the regular compensators.

I designed rocket sleds, I know how they originally meant to work, the real expense being the (separate) really expensive fuel.

Fuel for an hour or so is much less than fuel a main reaction drive would need, that part is understandable.



I may be overthinking this, but as far as I can see compensators are a separate component:

Compensators is the same tech as artificial gravity, just as earlier editions.

Both Gravitic and Reaction drives contains thrusters:

That would depend on whatever current Mongoose and/or Tee/Five terminology is.

I think we could term a lot of technical developments as gravitational based technology, not necessarily directly related.

Manoeuvre Drive Systems consist of thrusters and compensators.

Both Gravitic and Reaction drives contains thrusters.

Manoeuvre and Reaction drives seems to be used somewhat interchangeably.


As far as I can see a Manoeuvre Drive System consists of a drive (either gravitic or reaction) and a compensator.


I can't see any reason artificial gravity compensators couldn't be combined with reaction drives. It's clearly not the thruster itself that performs the compensation.

At this point, gravitational compensators are only colocated with the manoeuvre drive, whether this has to do with efficiency near the source of most of the gravitational force to be neutralized, or is actual requisite to do so.

It's possible that you can separate the gravitational compensators, and apply them to anything else that creates gravitational force, but that a rocket might be too hot to colocate.

 

[AnotherDilbert]

The same thing happens in a hovercraft, it is nothing to do with pushing against the road. or aircraft, or real world rocket, in space.

I still have no idea what you mean. Are you talking about rotating the ship or changing the ship's velocity vector (hence momentum)?

Yes, spacecraft have a velocity vector.
Yes, it takes a lot of acceleration to change the vector.
In space, all the acceleration comes from the drive.
Hence, you can't turn on a dime?

You have a momentum vector, it's how motorcycles do the wall of death.

Banked roads and in the extreme case "The Wall of Death" has everything to do with "pushing against the road" or rather letting the road accelerate you as it is a physical barrier.

Roads are banked so that the most of the resulting force on the car is perpendicular to the road, hence less sideways force trying to push you off the road. The car is accelerated around the corner by the road.
https://byjus.com/physics/banking-of-roads/

The wall of death: The motorcycle is accelerated in a circle by the wall imposing a centripetal force. Note that he is not driving perpendicular to the wall to compensate for gravity.
https://en.wikipedia.org/wiki/Wall_of_death


In space you have no road or wall to push against. All force, thrust, acceleration is imposed by the drive, hence can't be greater than rated drive acceleration.

 

[AnotherDilbert]

At this point, gravitational compensators are only colocated with the manoeuvre drive, whether this has to do with efficiency near the source of most of the gravitational force to be neutralized, or is actual requisite to do so.

It's not necessarily co-located, it's just paid for as part of the drive system. The drive system can be several components in several locations, while still being one single budget post.

It's possible that you can separate the gravitational compensators, and apply them to anything else that creates gravitational force, but that a rocket might be too hot to colocate.

A compensator is just artificial gravity, but in another direction.

I have difficulty imagining that you can build compensators that can compensate for 2 G from one drive, but not 2 G from another drive.

If the rules wanted to say that TL-15 compensators can counteract 9 G, but not 15 G, they would have to say so and made a table for that. They already have the uncompensated acceleration effects in the HBT description.

 

[Condottiere]

Unless inertial compensators are virtual, they take up volume.

Usually, deckplans indicate where that volume resides.

 

[phavoc]

That is just word games with non-Traveller definitions. In Traveller parlance "thruster" or "thruster plate" is the conventional gravitic M-drive.

By SSOM:
View attachment 1664
Attitude control is provided by a subsystem included in the "manoeuvre drive" system consisting of both thrusters and gyroscopes.

Whether the thrusters are movable or not is of course completely undefined by either CT or MT. Azipod is just a trademark for a specific movable motor mount. E.g. water-jet propulsion with movable nozzles have been around since the 30s and can provide side-ways thrust:

https://en.wikipedia.org/wiki/Pump-jet

Trust vectoring of rockets were used from the 30s and by most rockets e.g. the V2 and the Saturn V, so was a well known concept in the 70s.

https://en.wikipedia.org/wiki/Thrust_vectoring


There is no need to shut down the main thrusters to adjust the attitude the spacecraft, you just vector the main thrusters a bit reducing the thrust slightly, adding to aux. thrusters to rotate faster.

Not wanting to split words here. I was talking about the literal differences between the classes of thrusters and used our last actual working spaceship as an example of how main drives and secondary/tertiary thrusters work (as opposed to the fiction of SOM). The use of thruster plates would negate the need for a gyroscope (especially with not needing fuel). Gyroscopes are great to save fuel, but when you don't need to worry about that they become unnecessary. In the SOM model the AUX thrusters would the ones different than the main drive plates.

The azipods/thrusters have been around when outboard motors were invented. Today they are more advanced with the engines and their placements. For spacecraft I'd expect them to be spread more around the engine (say 4 at the bow and 4 at the stern) to give them more 365 degree control - plus the security of having multiple units in case of loss/failure.

Thrust vectoring should be reasonably expected from the magical M-drive. And you could turn the thrust 10 degrees to begin a turn - but you then have to point it back in the opposite direction to stop the movement you started or else your course will not be what you want. Shutting down MAY be more efficient, though its questionable, and it comes down to "it depends". The question of which sets are most effective greatly depends on your delta-v and whether or not your secondary units can do the job in the time given, or if you need to use your main thruster plates that you used for the last 2 days to generate your current vector.

 

[phavoc]

It's not necessarily co-located, it's just paid for as part of the drive system. The drive system can be several components in several locations, while still being one single budget post.



A compensator is just artificial gravity, but in another direction.

I have difficulty imagining that you can build compensators that can compensate for 2 G from one drive, but not 2 G from another drive.

If the rules wanted to say that TL-15 compensators can counteract 9 G, but not 15 G, they would have to say so and made a table for that. They already have the uncompensated acceleration effects in the HBT description.

It's hard to say exactly how all this works. Is there a central generator that creates a ship-encompassing field for the inertial dampener (which is your gravity field 'sink' and prevents you from bouncing around). Your grav plating could also emit an inertial field itself along with controlling your local field.

With the high-burn thrusters that allow for large G forces, one has to guess how those forces are compensated for. Is it via the inertial compensator field (And does it have an upper limit where it fails. And if it fails does how much of the failure is felt? All? Partial?) or do the grav plates themselves handle this (same questions PLUS what happens when a plate fails in the middle of a corridor. Are you walking, walking, spaltting, dead?

 

[AnotherDilbert]

Not wanting to split words here.

OK, sorry.

The use of thruster plates would negate the need for a gyroscope (especially with not needing fuel). Gyroscopes are great to save fuel, but when you don't need to worry about that they become unnecessary. In the SOM model the AUX thrusters would the ones different than the main drive plates.

Agreed, I can only guess it's a fail-safe. If power fails, batteries can provide some power, perhaps not enough for hungry thruster plates, but a gyro would still allow some control?

 

[AnotherDilbert]

It's hard to say exactly how all this works.

When in doubt, go back to basics:

LBB5'79, p17:
Tech level requirements for maneuver drives are imposed to cover the grav-plates integral to most ship decks which allow high-G maneuvers while the interior G-fields remain normal.

Or the detailed edition:

FF&S, p77:
Artificial gravity G compensators create an artificial gravity field in direct opposition to the axis of acceleration, thus negating the acceleration (up to the limit of the artificial gravity field).

Is there a central generator that creates a ship-encompassing field for the inertial dampener (which is your gravity field 'sink' and prevents you from bouncing around).

Sink? Dampener? What does that mean?

Artificial gravity is a force field, an acceleration, just like a gravity field.

Your grav plating could also emit an inertial field itself along with controlling your local field.

What is an inertial field?

With the high-burn thrusters that allow for large G forces, one has to guess how those forces are compensated for. Is it via the inertial compensator field (And does it have an upper limit where it fails. And if it fails does how much of the failure is felt? All? Partial?) or do the grav plates themselves handle this ...

FF&S and High Burn Thruster say 2 G compensators compensate 2 G, the rest is felt by the crew.

FF&S, p77:
Compensated Gs is the number of acceleration or evasion Gs negated by the compensator. The amount of Gs which can be compensated vary by tech level as shown on the table below.
...
Beyond these levels, all tasks are performed at one difficulty level higher (+1 Diff Mod) per G-turn applied.

...(same questions PLUS what happens when a plate fails in the middle of a corridor. Are you walking, walking, spaltting, dead?

Undefined, but as this is supposed to thousands of years old safe technology, I would guess it's a local weakening of the field, something like walking, walking, stumble, walking...

 

[Condottiere]

We have little idea how this stuff works ingame.

In Mongoose, the last mention is in High Guard, and only in connection to the manoeuvre drive.

As regards to artificial gravity tiles, I'm not sure if gravitational ping pong is still an option.

 

[phavoc]

When in doubt, go back to basics:

Or the detailed edition:




Sink? Dampener? What does that mean?

Artificial gravity is a force field, an acceleration, just like a gravity field.



What is an inertial field?



FF&S and High Burn Thruster say 2 G compensators compensate 2 G, the rest is felt by the crew.




Undefined, but as this is supposed to thousands of years old safe technology, I would guess it's a local weakening of the field, something like walking, walking, stumble, walking...

The challenge here is which version should be used to provide the explanation? Some are contradictory to others, and should the 81 edition supersede the 77 edition (for CT). And what about FF&S? There's the original one and then the revised one. Should I stick with GDW-published ones only, or do any of the licensee's count? Or would I just stick with the ones Miller had a hand in? Ideally I should be able to stay at least within a published edition to find continuity and not have to jump around to multiple versions published, in some cases, decades apart.

Assuming we go with the book editions - that the floor plating emits the field that acts as both a localized gravity well and an inertial dampening field (i.e. the longer-winded explanation provided FF&S where the person standing on the deck plate is not affected by the thrust from the M-drive - that's an inertial dampening field). Using that as our basis then we'd extrapolate that every square inch of deck plating emits a field that is rated for the maximum-G rating of the drive. This field works at a constant - but is only rated to a maximum level of the drive field. So somehow that should mean the deck plating for a 1G free trader is cheaper than one for a 6G courier? And in a small craft is there a tiny deck plate built into the flooring of the cockpit? If I retrofit a bigger drive into my free trader, do I have to rip out all my deck plating and install more powerful plating? Or is that resolved simply by routing more power through the plating to generate a more powerful field (which in that case would mean so long as you have power your hull plating matches your drive rating - nullifying the explanation to an extent).

If we assume the above is true, then would a small ship equipped with afterburners allow for the same level of nullification of the effects of the thrust when a ship goes to 10G? or 15G? That's not clear. Going with that same idea, assuming your field only works up to 2G and you hit 10G, that means you'd only be feeling the effects of 8G (the difference). The explanation says "along the axis of acceleration" - which in a 3D environment can be done in multiple dimensions simultaneously. I'm assuming they essentially mean the deckplating floor here.

The question I had about the field is that if all of this is by deck plating - just how far up does the field go? If we assume it goes up to the level of the dimensions of 1DT, then the upper level of the cargo deck of a subsidized trader would be beyond the reach of the deck plating and thus not have the benefit of the plating. This could be potentially countered by having deck plating on the roof, focusing downward - but then we'd have two potentially conflicting fields and would there be some sort of weird interface effect between one set pointing "up" and one pointing "down". A field generator would actually work better from an operationally point of view and would also have less questions and gyrations and possible "it just works" hand waviums. I'm not opposed to thing that we haven't a clue on how it works (jump drive, etc) - but I DO like internal consistency within the game system.

The 'sink' comment is related to an inernatial dampening field - it's just another way of expressing how the force of the acceleration is offset / absorbed by a 'sink' field that encompasses the ship. With deck plating it's got to be limited because deck plating is at every deck, and with ladders and other vertical access points you'd have to have some sort of field that would allow transition from deck to deck without affecting movement. Sure, said magical field could be variable, and putting more power in a section allows you to project it further upwards that allows for higher decks or atriums or any of the other possibilities you could find in a spaceship (even a diving swimming pool). A field generator actually resolves all these questions more handily with less mental gyrations.

GURPS rules have utility systems that generate artifical gravity and act as sumps for G that are limited by TL, with contragravity (aka anti-gravity) that can cancel gravity (but based on mass, not displacement) and then they have their combo systems that combine all three. GURPS also doesn't really cover how far the field extends from the deck plates. In some cases they provide similar explantion as other versions of Traveller, in other cases they explicitly call out things like contragravity (that is not clear in other version), and like all versions there are gaps in the explantions. I personally think of GURPS as the gold standard as far as details goes for all versions of Traveller.

None of these questions are critical to play - unless your gaming style is oriented around questions of these types because your players are creative little bastards and always thinking at the edge of the rules - or just plain think of things you don't. And while s/he who rolls the dice behind the GM screen is ultimately master of the gaming universe, it's nice to have things laid out so that you don't have to come up with your own rules/explanations or else just wave them off and skip it. And the gearhead inside me likes the gaming universe consistency.

 

[Gavain]

To me it makes most sense that the compensation for the M-drive is actually supplied by the M-drive itself. It is generating the field that is driving the ship why wouldn't the dampening field for the ship come from the drive? It might also explain why the M-drives are usually in the rear of the ship.
Putting the compensators in the floor would, to me, be applying the force in the wrong direction as most MG ships have the their decks perpendicular to the main direction of travel.

 

[Sigtrygg]

The acceleration compensators have to be able to counteract lateral "g forces" not just the thrust of the engines.

Gravity: Most ships have grav plates built into the deck flooring. These plates
provide a constant artificial gravity field of 1 G. Acceleration compensators are also
usually installed, to negate the effects of high acceleration and lateral G forces
while maneuvering. A ship's passengers would be unable to tell whether they were
moving through space or grounded on a planet without looking out a viewscreen.

 

[Condottiere]

Mini jumpspace.

When activated, you're no longer in Kansas.

Well, partially.

Schrodinger inertial field.

 

[AnotherDilbert]

To me it makes most sense that the compensation for the M-drive is actually supplied by the M-drive itself. It is generating the field that is driving the ship why wouldn't the dampening field for the ship come from the drive?

The m-drive does not produce a field. It produces thrust, a force acting on a specific location (MT RM, p56; FF&S, p73).

A field can potentially act on all locations:
https://en.wikipedia.org/wiki/Field_(physics)
https://en.wikipedia.org/wiki/Thrust

Examples:
A jet engine produces thrust, a force on the engine. That force is propagated to the rest of the aircraft through the frame or hull, until the seat pushes the pilot. A bird a bit away is unaffected.

A gravity field affects everything evenly. No part of the aircraft would push against the other, it would be in "free fall" ("weightlessness"). The pilot would not perceive the seat pushing him. A nearby bird would be accelerated with the craft.

Putting the compensators in the floor would, to me, be applying the force in the wrong direction as most MG ships have the their decks perpendicular to the main direction of travel.

The field can apparently be tilted:

The purple vector is the direction of the field, producing both a downward acceleration into the floor (artificial gravity), and a forwards acceleration so the person accelerates with the ship instead of slamming into the back wall as the ship accelerates sideways (compensator).

For illustrative purposes I used grav plates in the walls to show how the AG field can do both at the same time, by producing a tilted field.

It's a field because it affects the whole room, not just a single point. The whole person is accelerated evenly, not just tugged in a single location.


I'm sorry if this seems condescending, but it seems to me that some posters don't understand what a "field" is in physics.

 

[AnotherDilbert]

The challenge here is which version should be used to provide the explanation?

No edition is very detailed, they give snippets of hints. FF&S is the most detailed, as usual.

Some are contradictory to others, and should the 81 edition supersede the 77 edition (for CT).

Neither LBB2'77 nor LBB2'81 says anything whatsoever about compensators nor artificial gravity. That all comes from LBB5, and is identical in both editions.

And what about FF&S? There's the original one and then the revised one.

And the discussion about compensators is identical in both, and consistent with (if more detailed than) CT.

Should I stick with GDW-published ones only, or do any of the licensee's count? Or would I just stick with the ones Miller had a hand in? Ideally I should be able to stay at least within a published edition to find continuity and not have to jump around to multiple versions published, in some cases, decades apart.

Anything you like, for your game? I'm not aware of any edition that is inconsistent with CT, except possibly T5 that gives it a vague hand-wave without any explanation. I'm of course not familiar with all editions.

Assuming we go with the book editions - that the floor plating emits the field that acts as both a localized gravity well and an inertial dampening field (i.e. the longer-winded explanation provided FF&S where the person standing on the deck plate is not affected by the thrust from the M-drive - that's an inertial dampening field).

OK, so long as we agree it has nothing to do with dampening inertia?

The G compensator is just an artificial gravity field that accelerates you with the ship, so you are not slammed into the walls when the ship accelerates.

Using that as our basis then we'd extrapolate that every square inch of deck plating emits a field that is rated for the maximum-G rating of the drive. This field works at a constant - but is only rated to a maximum level of the drive field.

It is rated to some maximum, dependent on TL.

In MgT2'22 it's rated specifically to main drive rating, yes.

So somehow that should mean the deck plating for a 1G free trader is cheaper than one for a 6G courier?

No edition goes into that much detail for a peripheral system. It would have a different base TL.

And in a small craft is there a tiny deck plate built into the flooring of the cockpit?

That would be up to you, CT HG only says "ship" defined to craft of 100 Dt or bigger.

It's generally assumed, I think, to affect small craft too and the entire small craft at that. MT and later makes that explicit.

If I retrofit a bigger drive into my free trader, do I have to rip out all my deck plating and install more powerful plating? Or is that resolved simply by routing more power through the plating to generate a more powerful field (which in that case would mean so long as you have power your hull plating matches your drive rating - nullifying the explanation to an extent).

It's related to TL, not power, in any edition I know of, so if you install a more powerful drive, with a higher base TL, I guess you have to replace the compensators too, yes.

If we assume the above is true, then would a small ship equipped with afterburners allow for the same level of nullification of the effects of the thrust when a ship goes to 10G? or 15G? That's not clear.

M-drives don't have afterburners. If you add HBT rockets, they are explicitly not compensated in MgT.
With FF&S it would depend on the rating of the compensators you installed, as they have a separate rating.

Going with that same idea, assuming your field only works up to 2G and you hit 10G, that means you'd only be feeling the effects of 8G (the difference).

Yes.

The explanation says "along the axis of acceleration" - which in a 3D environment can be done in multiple dimensions simultaneously. I'm assuming they essentially mean the deckplating floor here.

Chosen coordinate system is irrelevant.
"along the axis of acceleration" refers to the ship's acceleration vector.
FF&S makes a difference between steady acceleration and evasion (erratic acceleration in varying directions).

The question I had about the field is that if all of this is by deck plating - just how far up does the field go?

MT says the entire ship or nothing. No edition specifies any limitation by deck height or anything else.

If we assume it goes up to the level of the dimensions of 1DT, then the upper level of the cargo deck of a subsidized trader would be beyond the reach of the deck plating and thus not have the benefit of the plating.

Nothing even hints at any such limitation.

This could be potentially countered by having deck plating on the roof, focusing downward - but then we'd have two potentially conflicting fields and would there be some sort of weird interface effect between one set pointing "up" and one pointing "down".

Gravity fields superimpose without interference, so I have no idea why we would posit any such thing.

A field generator would actually work better from an operationally point of view and would also have less questions and gyrations and possible "it just works" hand waviums. I'm not opposed to thing that we haven't a clue on how it works (jump drive, etc) - but I DO like internal consistency within the game system.

The artificial gravity system is a "field generator", distributed through the ship.

Do you mean a central machine in a specific location? In such case I have no idea how it would project an even field throughout the ship, I would assume it would follow an inverse square law as usual.

The 'sink' comment is related to an inernatial dampening field - it's just another way of expressing how the force of the acceleration is offset / absorbed by a 'sink' field that encompasses the ship.

A sink is not a field. A sink is where you dump excess something like a drain or heat sink. We don't dump excess inertia or gravity, it's just an artificial gravity field.

With deck plating it's got to be limited because deck plating is at every deck, and with ladders and other vertical access points you'd have to have some sort of field that would allow transition from deck to deck without affecting movement. Sure, said magical field could be variable, and putting more power in a section allows you to project it further upwards that allows for higher decks or atriums or any of the other possibilities you could find in a spaceship (even a diving swimming pool). A field generator actually resolves all these questions more handily with less mental gyrations.

No, a central machine makes it much worse. E.g. a field from a point source would generally be spherical and lose strength with distance, a field between two plates are much closer to uniform.

Luckily we don't have to guess, it's specified in many editions to be grav plates in the decks.

GURPS rules have utility systems that generate artifical gravity and act as sumps for G that are limited by TL, with contragravity (aka anti-gravity) that can cancel gravity (but based on mass, not displacement) and then they have their combo systems that combine all three.

Contragravity is not the same as artificial gravity in CT and MT. Contragravity is propulsion system, or rather a buoyancy system.

GURPS Traveller posits the exact same grav plates as CT:

GURPS Starships, p7:
GRAVITY
All modern starships use artificial gravity plates in the decking.

GURPS Starships, p39:
GURPS Traveller vessels, if equipped with artificial gravity, are assumed to have compensation for transient high-G maneuvers (see p. GTl07).

"Utility Systems" are just a way of packaging several systems in a neat package covering a set volume and/or mass, to simplify ship design.

GURPS also doesn't really cover how far the field extends from the deck plates.

No edition does?

In some cases they provide similar explantion as other versions of Traveller, in other cases they explicitly call out things like contragravity (that is not clear in other version), and like all versions there are gaps in the explantions. I personally think of GURPS as the gold standard as far as details goes for all versions of Traveller.

OK, you can use GURPS if you like, I see no contradiction in regard to artificial gravity or contragrav. FF&S is much more detailed.

None of these questions are critical to play - unless your gaming style is oriented around questions of these types because your players are creative little bastards and always thinking at the edge of the rules - or just plain think of things you don't. And while s/he who rolls the dice behind the GM screen is ultimately master of the gaming universe, it's nice to have things laid out so that you don't have to come up with your own rules/explanations or else just wave them off and skip it. And the gearhead inside me likes the gaming universe consistency.

As far as I can see, it is fairly straight-forward. If you have artificial gravity, you can use the same tech to can get G compensation by varying the strength and direction of the artificial gravity field, no extra magic needed.

The magic tech is artificial gravity, compensation is just an application of that tech.

 

[phavoc]

The m-drive does not produce a field. It produces thrust, a force acting on a specific location (MT RM, p56; FF&S, p73).

A field can potentially act on all locations:
https://en.wikipedia.org/wiki/Field_(physics)
https://en.wikipedia.org/wiki/Thrust

Examples:
A jet engine produces thrust, a force on the engine. That force is propagated to the rest of the aircraft through the frame or hull, until the seat pushes the pilot. A bird a bit away is unaffected.

A gravity field affects everything evenly. No part of the aircraft would push against the other, it would be in "free fall" ("weightlessness"). The pilot would not perceive the seat pushing him. A nearby bird would be accelerated with the craft.



The field can apparently be tilted:
View attachment 1684
The purple vector is the direction of the field, producing both a downward acceleration into the floor (artificial gravity), and a forwards acceleration so the person accelerates with the ship instead of slamming into the back wall as the ship accelerates sideways (compensator).

For illustrative purposes I used grav plates in the walls to show how the AG field can do both at the same time, by producing a tilted field.

It's a field because it affects the whole room, not just a single point. The whole person is accelerated evenly, not just tugged in a single location.


I'm sorry if this seems condescending, but it seems to me that some posters don't understand what a "field" is in physics.

Oh, I think lots of us understand what a "field" means. And if you are going to be tossing out physics definitions then you should know that not every field is omnidirectional. Depending on the wave form you can very much make a directional field, or you can manipulate it mechanically/electrically. There are entire fields of technology (pardon the pun) that utilize directional fields of various types (quantum, magentic, gravitational... crap, I don't want to have to go find my old physics books).

You argued (and used the quote) upthread:
(LBB5'79, p17 Tech level requirements for maneuver drives are imposed to cover the grav-plates integral to most ship decks which allow high-G maneuvers while the interior G-fields remain normal.

Or the detailed edition: (FF&S, p77
Artificial gravity G compensators create an artificial gravity field in direct opposition to the axis of acceleration, thus negating the acceleration (up to the limit of the artificial gravity field)

The illustration above is incorrect because with an inertial dampening field the person within it perceives no acceleration or movement of the ship at all - up to and including maneuvers at any angle. As long as the maneuvers are within the parameters of what the field can handle. We, on this planet, have no perception of the orbital movement or rotation of the planet. Traveller deck plating (which wouldn't be separate as shown in the illustration) is positing the same. Traveller drives provide thrust along the main axis, hence the ship has to rotate to decelerate. Being able to turn or rotate the ship doesn't factor into that - steering and headings aren't used. So if you take the FF&S explanation at face value, your maneuver drive thrusts rearward at a 90 degree angle then your G compensators create a field at a 180 degree angle so that the force of the accelaration is "downwards" instead of "rearwards" - directions in quotes since its space.

So the explanation you provide personally (or perhaps it's just your interpretation of it) does not match the "artificial gravity field in direct opposition to the axis of acceleration" definition. Unless you want to interpret that statement as the deckplates are emitting a localized omnidirectional field. Since it specifies "deck plating" that would (or should) mean your field is only omnidirectional as far as being in a 180 degree arc of the deck plate itself. Or at least that's my personal interpretation of all this. We have been at odds before and this may be another occurence of that.

The inclusion of a "nearby bird" works so long as it's in the affected area - except that's vague. Walking on the outside of the ship you have to use magnetic boots to walk on the hull - so the field has a distance limitation. And, using the provided quotes above, that field must extend no further than 3m - unless you want to interpret it to be greater than that. At a minimum it has to extend that far or else at 2.9 meters you are outside the field and become affected by the thrust. Maybe that was the intent, but what was/is written is rather vague. Additional editions don't really do a lot to clear it up (sad, since that's one of the reasons - aside from selling the same stuff with a different smell - to publish a 2nd/3rd/4th/etc edition).

As things try to get more detailed they also tend to start exposing large holes in the gaming universe because the "this sounds cool!" idea has to have a whole host of other things supporting it to pass the sniff test. Ergo we get the hand-wavium applied. The goal, I'd hope, for any game designer is to minimize the hand-waviums. To be fair, sometimes you have no choice if you want the cool idea but still want fun in your game. Prime example is that most editions throw out the concept of mass because they didn't want to get bogged down with it. It's there but we hand-wave it away.

 

[phavoc]

No edition is very detailed, they give snippets of hints. FF&S is the most detailed, as usual.


Neither LBB2'77 nor LBB2'81 says anything whatsoever about compensators nor artificial gravity. That all comes from LBB5, and is identical in both editions.


And the discussion about compensators is identical in both, and consistent with (if more detailed than) CT.


Anything you like, for your game? I'm not aware of any edition that is inconsistent with CT, except possibly T5 that gives it a vague hand-wave without any explanation. I'm of course not familiar with all editions.



OK, so long as we agree it has nothing to do with dampening inertia?

The G compensator is just an artificial gravity field that accelerates you with the ship, so you are not slammed into the walls when the ship accelerates.




It is rated to some maximum, dependent on TL.

In MgT2'22 it's rated specifically to main drive rating, yes.



No edition goes into that much detail for a peripheral system. It would have a different base TL.



That would be up to you, CT HG only says "ship" defined to craft of 100 Dt or bigger.

It's generally assumed, I think, to affect small craft too and the entire small craft at that. MT and later makes that explicit.



It's related to TL, not power, in any edition I know of, so if you install a more powerful drive, with a higher base TL, I guess you have to replace the compensators too, yes.



M-drives don't have afterburners. If you add HBT rockets, they are explicitly not compensated in MgT.
With FF&S it would depend on the rating of the compensators you installed, as they have a separate rating.



Yes.


Chosen coordinate system is irrelevant.
"along the axis of acceleration" refers to the ship's acceleration vector.
FF&S makes a difference between steady acceleration and evasion (erratic acceleration in varying directions).



MT says the entire ship or nothing. No edition specifies any limitation by deck height or anything else.


Nothing even hints at any such limitation.


Gravity fields superimpose without interference, so I have no idea why we would posit any such thing.



The artificial gravity system is a "field generator", distributed through the ship.

Do you mean a central machine in a specific location? In such case I have no idea how it would project an even field throughout the ship, I would assume it would follow an inverse square law as usual.



A sink is not a field. A sink is where you dump excess something like a drain or heat sink. We don't dump excess inertia or gravity, it's just an artificial gravity field.



No, a central machine makes it much worse. E.g. a field from a point source would generally be spherical and lose strength with distance, a field between two plates are much closer to uniform.

Luckily we don't have to guess, it's specified in many editions to be grav plates in the decks.



Contragravity is not the same as artificial gravity in CT and MT. Contragravity is propulsion system, or rather a buoyancy system.

GURPS Traveller posits the exact same grav plates as CT:



"Utility Systems" are just a way of packaging several systems in a neat package covering a set volume and/or mass, to simplify ship design.




No edition does?


OK, you can use GURPS if you like, I see no contradiction in regard to artificial gravity or contragrav. FF&S is much more detailed.



As far as I can see, it is fairly straight-forward. If you have artificial gravity, you can use the same tech to can get G compensation by varying the strength and direction of the artificial gravity field, no extra magic needed.

The magic tech is artificial gravity, compensation is just an application of that tech.

I suppose we can agree to interpret things a bit different. At this point the discussion isn't really going anywhere or contributing what I think is helpful/useful discourse.

The only other comment I would make is that I try not to utilze multiple editions within the same discussion. Bouncing around using source materials from different versions that have, in some cases, removed or restated a rule isn't always helpful. I've lost count of the versions being used. Generally speaking I prefer to stick within a singular setting - at least on a per argument basis. Unless the explanation/definition is the same in every version then they all kind of have to stand on their own within their own version/setting. At least that's how I see things.

Thanks for your contributions.