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CT Only: GRAVITY! ...And the M-Drive...and Man...and Worlds.

with stem-cell cocktails re-stimulating bone growth post-adolescence and nano-surgically infused mineral-rich serum for increased bone strength and calcium carrying capacity... er whatever.

In Traveller terms, it's a drug called Standard. That fits with other drugs known in the game, like Panacea, Fast Drug, Slow Drug, Combat Drug, Medical Drug, and the like.
 
with stem-cell cocktails re-stimulating bone growth post-adolescence and nano-surgically infused mineral-rich serum for increased bone strength and calcium carrying capacity... er whatever.

Right now I stipulate that the Calcium loss gene was a very common gene fix just after the Solomani expansion into space, thus it is a common fix throughout the Imperium.
 
Pg. 55 of TTB

More CANON!

Look at the Typical Activities chart on the right hand side of the page. III. B. says, again, that unstreamlined craft do not land. This refers to the rule on page 60 where it says streamlining is required if a ship needs to enter an atmosphere or skim fuel.

Nothing about escape velocity, J-1 ships, and Worlds Size 9+, but that's part of the question on this thread.
 
I love so many of the implications S4 has drawn about the nature of arriving, or not arriving, or taking off, or not taking off from worlds from the text of the Basic Traveller rules.

It fits in much more with the way I've always seen the game playing. In particular, I've never much liked some of the later notions of that got introduced into the game: that the PCs can simply hop back and forth around a planet using the gravitic drives of their ships; that a merchant starship ship is essentially a floating fortress that can hang in the air on a planet and threaten anyone on the ground they don't like; that starships can gently land anywhere instead of needing a stretch of runway available for both landing and taking off.

In short, S4 is focusing on all the implications that provide limits on travellers and travel. And I think limits are awesome. It's why the Mercenary Cruiser (Type C) carries two 50-ton cutters, each with an ATV module (which includes an ATV).

Most importantly, these implications mean that once the PCs arrive in system, they have to exit their heavily armored and heavily armored ships and go get into harm's way if they're going to go get what they want to get.

The PCs might be able to land their ships. Or they might have to use a Ship's Boat. The combination and permutations S4 talks about as we mix and match ship qualities with different world environments mean there will be variety in how the PCs must interact with arriving on planet. This is good! It means different worlds automatically have different feel. It means the Players must make choices about how to handle different situations.

***

This ties into something I've been thinking about for a few weeks:

How much fuel does a starcraft (streamline) or spacecraft use getting from surface into orbit?

The amount listed in Book 2 says the fuel load listed can get you one-way from system to system, which implies it about a) Jumps and b) traveling through space.

But we know we're going to be burning fuel to get off planet. (It might be a lot!)

The question matters, of course, because it might be that a loaded ship only has enough fuel to, say, get back into orbit, jump, and then get to another system.

If a ship lands, refuels, then takes off again... will it have enough fuel (or not) to land and then take off once more? I haven't found any mention of this in Books 1-3, and was wondering what folks on this thread thought.

[Note: Given what I have written above, I'm curious about working from the conditions S4 (and Mike) have laid out above, and using the original Classic Traveller rules, for my answer. Later issues of canon from later editions of the game are of not interest to me.]
 
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I love so many of the implications S4 has drawn about the nature of arriving, or not arriving, or taking off, or not taking off from worlds from the text of the Basic Traveller rules.

S4 has a good feel for his one set of interpretations...
Not all of his interpretations are shared by the majority, and many are incompatible with later editions explicit renderings.

Still, He's got a lot of good starting points for the novice CT-only non-OTU GM.
 
In short, S4 is focusing on all the implications that provide limits on travellers and travel. And I think limits are awesome.

Exactly the way I look at it, sir!

From the recent THREAD ON THE TRAVELLER ADVENTURE, I speculated on the challenges the March Harrier would face on each of its given subsidy worlds.

Doing this kind of thing makes the game more interesting, I think, for players. It makes places (worlds) come alive, instead of being just another place to land.





How much fuel does a starcraft (streamline) or spacecraft use getting from surface into orbit?

Not enough to even both counting, I would think, from a game perspective. I say that because the M-drive works exclusively on electricity, and that power is generated by the ship's powerplant. Most PPs on ships have fuel for four weeks.

It takes about 2,000 seconds (about half an hour or so) for a 1G vessel to reach orbit, according to page 54 of TTB.

So, it requires a very small percentage of fuel tankage. I'd just re-fuel the PP every 4 weeks, eyeballing it. Or...to be easy, just have the crew pay for the PP fuel after 4 jumps, or so (about 8 weeks), unless the ship goes on a long in-system journey.

As for refueling for ground to orbit jaunts, it's not worth counting.

It changes later, in other versions of Traveller. But, for CT, the M-Drive is used for atmospheric operations--not a grav drive, as seen in MT.

You could assume that a grav drive is part of the ship's hull or drive cost--it all comes packaged together, using no more fuel than the M-Drive requires--but that doesn't address the long time it takes to reach orbit.

1. Unstreamlined ships cannot enter atmosphere at all. TTB pg. 60.

2. The Typical Travel Times table shows a long, long time for orbit with streamlined craft. TTB pg. 54

This means that the M-Drives, built for inter-system Traveller, lumber and wallow when used for atmospheric operations. They're inefficient.

33 Minutes to get a streamlined 1G craft to orbit, to me, makes me think that the 1G ship is gaining all the lift it can from the atmosphere and the streamlining in conjunction with the M-Drive. We're not talking about the Millennium Falcon zipping up and out of here. This is more like a big, lumbering Boeing 747, catching lift and taking an elliptical, steady course to gradually lift through the clouds and out into space.





The amount listed in Book 2 says the fuel load listed can get you one-way from system to system, which implies it about a) Jumps and b) traveling through space.

See the Typical Activities outline on page 55 TTB. A ship typically arrives in a star system, having used all of its jump fuel, but still has four weeks of PP use for in-system use. Second step is to local a gas giant and refuel. If no gas giant present, or the ship isn't streamlined, then the ship must make port (high port, if the ship isn't streamlined), as detailed in the third step.
 
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S4 has a good feel for his one set of interpretations...
Not all of his interpretations are shared by the majority, and many are incompatible with later editions explicit renderings.

Still, He's got a lot of good starting points for the novice CT-only non-OTU GM.

Thanks for the back-handed compliment, but what, from what I've said, is non-OTU from a CT-only perspective? Just the White Dwarf rocket stuff?
 
the novice CT-only non-OTU GM.

We're in the Classic Traveller sub-forum.

And the thread is marked "CT Only."

And S4 is only working from Basic Traveller rules quotes and early CT adventures. Which run counter to almost all assumptions found in later editions and the entirety of the OTU.

So, yes? The conversation is about CT-only, Non-OTU? At least its working that way for me. S4 may be able to fit it into the OTU. But certainly at this point in the conversation it is not required. We're simply hashing out what's right there in the text.

What the "novice" has to do with anything I have not a clue. I can only assume it means that you think "expert" play is playing editions beyond CT or only in the OTU. But that wold be nonsensical... so I must be wrong.

Anyway, people are having this conversation in a CT forum, talking about CT rules, in a thread labeled CT-Only. And it seems to be going pretty well.
 
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I have been pondering a related question; What is required for a wilderness landing?

Right now I am leaning towards a wilderness landing requires a ship with Streamlining 2g+ and a Model 2 or better Computer. (Note I assume that CTs Computer is a stand-in for a ship's electronic suite).

As for the larger question of launching low g ships a number of 3rd party products supposed gravity assist grids as parts of downports.

But I for one prefer slightly larger merchants with suitable sub-craft.
 
See the Typical Activities outline on page 55 TTB. A ship typically arrives in a star system, having used all of its jump fuel, but still has four weeks of PP use for in-system use. Second step is to local a gas giant and refuel. If no gas giant present, or the ship isn't streamlined, then the ship must make port (high port, if the ship isn't streamlined), as detailed in the third step.

This I get.

My question was whether or not taking off from a world eats enough of the PP fuel that a ship could, or could not, make several take offs and landings on the same world.

You suggest it could make several takes offs and landings without needing to refuel because you see the fuel cost of taking off as insignificant. (Again, no grav drives in my little focus of the conversation. And I am only talking about streamlined ships on worlds where streamlining will work.)
 
I have been pondering a related question; What is required for a wilderness landing?

Right now I am leaning towards a wilderness landing requires a ship with Streamlining 2g+ and a Model 2 or better Computer. (Note I assume that CTs Computer is a stand-in for a ship's electronic suite).

As for the larger question of launching low g ships a number of 3rd party products supposed gravity assist grids as parts of downports.

But I for one prefer slightly larger merchants with suitable sub-craft.

Why 2g+? (Not arguing, asking for elucidation).

For me, a rocking Pilot roll might also be required or risk taking some damage on the way in -- and on the way out. (The lack of landing infrastructure might be a problem.)
 
I have been pondering a related question; What is required for a wilderness landing?


Along with the other important issues you list, I was always worried about ground pressure.

Either put her down in water, which raises all sorts of other issues/problems, or find some place "strong" enough to hold her.
 
Also: For my "taking off and landing and taking off once more" notion, I see the streamlined ships similar in maneuverability to Space Shuttles... that is, not a lot. They get lift to get into orbit, and they get lift to ascend safely. But they don't fly like airplanes.

Once they get into orbit they'll have to send some time wheeling around to line ups their new flight path to land again. And per infojunkey's questions, if they're planning on landing on a place that is not a starport there will be plenty of complications.
 
I have been pondering a related question; What is required for a wilderness landing?

I assume that you're not talking about landing in the ocean or a lake. I know that we forget about that a lot. I have in the past.

That's one option. Have the crew look for a nice little lake to set down in/on.





Right now I am leaning towards a wilderness landing requires a ship with Streamlining 2g+ and a Model 2 or better Computer. (Note I assume that CTs Computer is a stand-in for a ship's electronic suite).

I'd say that a standard 1G M-Drive should be able to handle wilderness landing, given enough space to land.

I don't think this is covered anywhere, but there may be a JTAS article, or some paragraph in an adventure that would help us with this question.

In TTA,
it is suggested as an option to take the entire ship from the Starport to the small town of Itzeny to rescue the lumberjack part of the crew, if they are in trouble. No special wilderness notes are given.



There are things that we don't know about the M-Drive. Can it be used to hover? I would think so, but it's not really spelled out. My reasoning would be that anti-grav technology is probably used in conjunction with the M-Drive (which is a version of that tech). I think an air/raft or a person using a grav belt can hover, so I would think a starship could too.

But, I think this is probably up to the Ref and his version of his Traveller universe.

If starships can hover, then landing in any flat space should be fairly easy out in the wilderness.

If starships cannot hover, then the ship probably needs a run-way. I'd think of supply planes landing on islands and short runways of a couple thousand feet during WWII. A quick rule of thumb: Starships need a couple thousand feet (though I'm more of a mind that the M-Drive allows hover.)

Given either situation, especially in light of the 1G March Harrier and the example I gave you from TTA, I'd say that no special minimum requirements are needed.
 
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This I get.

My question was whether or not taking off from a world eats enough of the PP fuel that a ship could, or could not, make several take offs and landings on the same world.

You suggest it could make several takes offs and landings without needing to refuel because you see the fuel cost of taking off as insignificant. (Again, no grav drives in my little focus of the conversation. And I am only talking about streamlined ships on worlds where streamlining will work.)

Yeah, I'm thinking the M-Drive is used, and the M-Drive eats electricity at basically the same rate whether it's just turned on or pushing out 1G of acceleration.

Therefore, the PowerPlant is the fuel eater, and you've got 4 weeks of operation. That's 4 weeks of continual operation, whether you're floating in orbit, making burns to change vector in combat, landing on a world, or pushing full acceleration out to jump point.




You could put this into hours, if you like.

The March Harrier has 10 tons of fuel that supports the PP for four weeks.

That's 672 hours of fuel.

If it takes 30 minutes to land and 30 minutes to make orbit (for easy figuring--landing may take less time, and orbit, on average, costs 33+ minutes--all depends on world size), then just take off 1 hour per landing.

Take off any hours spend traveling through the atmosphere.

Look at the Travel Times table when moving to the Gas Giant or to Jump Point or any in-system maneuverings and take off those hours.

Every 67 hours spent is 1 ton of fuel.

Is something like that what you are looking for?
 
<Shrug> I don't think there is a canon answer to the question of fuel use during takeoff- more a matter of what effect you want.
 
lots of deckplans show neither feet nor wheels for any kind of pier landing on any kind of surface.

That's an excellent argument for a ship's hover ability.





Up-thread, I speculate that the M-Drive on a starship is inefficient. But, I looked at the orbit times for grav vehicles, and they're even longer.

An air/raft and a G-Carrier (and grav belt) can make orbit in a number of hours equal to the world's Size.

The speeder, built for interface, can make orbit in one hour.
 
That's an excellent argument for a ship's hover ability.

probably a better argument for wanting to cram as much "game-action" into a boat as possible.

imtu I just say a boat can have its specified m drive or, at a rating of one lower, vtol - endless hover. otherwise it has to land or take-off but can't hover.
 
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