Downports and landing non streamlined ships.

[Arkathan]

I would call fed standard partially streamlined. The saucer section is specifically meant to be a streamlined lifeboat.
The engines and saucer are connected to a cylindrical body by wing shaped struts, not trestle frames.
Voyager is intended to be streamlined, and has the landing gear.

 

[phavoc]

So I get highports but what exactly does a downport do?

Also, why can’t non streamlined ships not land on surface?
I mean all the video games allow it.

Downports are typically the primary or only place for ships to land on smaller population, lower tech worlds, or those worlds that don't get much traffic (which tend to be lower tech, smaller population). For busier worlds downports tend to take smaller craft while the larger freighters and liners dock in orbit.

Generally speaking, the larger the ship the more unwieldy it is in an atmosphere, and for ships that don't need to land then they simply don't.

The rules are very fuzzy about whether or not ships have anti-grav/contragravity for lift off. Some argue tail-sitters are the norm (the MT Starship Operations goes into detail how ships like a scout or free trader "land" using their drive like a tail-sitter and then come parallel to the ground). I think that over-complicates something that should be relatively easy to explain - ships have this as a norm and they can ascend/descend vertically without issue. Since this is Traveller there are various degrees of thought on the matter and keyboard have been honed to a razor's edge to debate this. My advice is keep it simple and basic unless you need to change it.

A non-streamlined ship could be a sphere. It's not going to fly super-fast in-atmosphere, but who really cares if a 2,000 ft diameter sphere can only travel 200kph in an atmosphere to take off, hover or land? Assuming one does so vertically you'd clear the atmosphere in 45min at that speed. A partially streamlined or fully streamlined ship may ascend vertically and then kick in it's drives to accelerate and take say a 45 or even 90 degree angle to move faster. Being semi or fully streamlined means less air resistance and thus it's faster in an atmosphere. However if you are just taking off or landing it's not really a big deal - unless, perhaps, you are running from authorities, bounty hunters, crazed humans with metal in their skin, etc. Then your speed is very important.

Structurally most ship configurations should support themselves to land - though the landing area and types of landing gear can make or break a ship. As others have pointed out some configurations in sci-fi make sense, others may be more challenged. Structurally a Traveller ship is pretty strong so just use common sense and you should be fine.

 

[Condottiere]

You could probably leverage a large manoeuvre drive factor into countering physical atmospheric turbulence, as opposed to just neutralizing the effects internally with inertial compensation.

 

[Reisender]

You could probably leverage a large manoeuvre drive factor into countering physical atmospheric turbulence, as opposed to just neutralizing the effects internally with inertial compensation.

Sure, you can always introduce some technology to explain anything in science-fiction, but keep in mind that once introduced it can not be taken back. In the end why bother to give ships an elaborated form if your technology is capable of making everything fly. In that case I would choose a form that gives me the most volume at the lowest cost, in other words a cube or sphere.
But yes, maybe the classification of hull configurations, or at least the impact on flying and landing ability, becomes irrelevant with a high enough TL.

 

[Sigtrygg]

This has been an issue with Traveller for a long time, not quite on the scale of Star Trek but an issue non the less.

Consistency in the application of the fictional technologies and the ramifications of those technologies.

Take the m-drive for example:
first it was hinted at to be a fusion rocket, then it was described as such, then it went undescribed, then it was described with so much handwavium gobbledygook, then it was a plasma rocket and now we have the 'gravitic drive'

How about nuclear damper technology - if you have the control of the strong and weak nuclear forces to the degree suggested then transmutation of elements becomes trivial.

Why is antimatter TL16 when all you need are particle accelerators, solar power and magnetic/gravitic storage - nuclear damper technology would once agin facilitate the 'mass production ' of antimatter.

Just how strong can you make artificial gravity?

 

[Condottiere]

Application might require that additional technological level.

Sensors, in theory, should be able to tell atmospheric conditions, and predict them locally, so can brace the spacecraft.

It's at this point where whether the manoeuvre drive creates a field effect does become relevant, otherwise it would be vectoring thrust.

 

[Reisender]

It's at this point where whether the manoeuvre drive creates a field effect does become relevant, otherwise it would be vectoring thrust.

Actually I think M-drives start out as a replacement of the main thrust with the same idea to propel the craft forward. As with thruster the direction can be changed slightly to change the course. Early spacecrafts even may still retain some small thrusters/nozzles at certain locations on the hull to "fine tune" the orientation of the vessel, e.g. for docking maneuvers. These might be replaced by devices using the M-drive later on.
If you look at Traveller ships in art you can see what appear to be thrusters even though these ships use M-drives. This might be just a legacy of Classic Traveller but it is still there. Sometimes even some glowing is shown behind these, which does not make much sense for M-drives.
There was a picture/diagram in Classic Traveller showing how a spaceship would accelerate the first half its journey then turn around to decelerate the second half. But I don't know if they had M-drives in mind back then.
What a M-drive produces is still called Thrust-<Rating> in the stats for a ships.

I'm pretty sure that we are leaving the purpose of this threat now, so this will be my last post in here.
There is probably a reason why not every detail about how certain things work are given in the rulebook(s). In the end this should remain a game and not turn into a simulation. And how exactly a M-drive or J-drive works is probably only interesting to very few people. For most people it is enough that that they do what they do. And it leaves enough room for everyone to come up with their own explainations if they desire.

 

[Condottiere]

As I recall, there was one explanation in that a gravitic drive was integral to the manoeuvre drive, allowing belly flops.

I'm thinking Tee Five.

 

[Arkathan]

Earlier. MegaTraveller.

 

[ottarrus]

Folks, comparing tech from Star Trek and Traveller has never matched up well.
Even the most generous TL estimates put vital Star Trek technologies [transporters, replicators, tractor beams, etc.] at beyond what the Imperium will ever achieve. Simply put, they're off the table. This would also imply that Star Trek gravity control systems are similarly advanced.
Beyond that, we also all agree that Star Trek plays very fast and very loose with basic laws of physics that Traveller still respects and applies to its technologies.
So using Star Trek as technological example of why a Traveller ship can do 'x' and 'y' is a non-starter.

As Traveller technologies are currently applies, dispersed structure ships simply cannot safely land on any world with any kind of appreciable atmosphere, say Very Thin or better. They can CRASH on such worlds, but they're not leaving again.
Whether or not a Close Structure spacecraft can do so is, I suppose, an IMTU decision. In my view, the lack of lifting and control surfaces make this an extraordinarily difficult piloting task. What's more, I would require that the ship spend tonnage on landing gear. But YTUMV.

 

[AndrewW]

Folks, comparing tech from Star Trek and Traveller has never matched up well.
Even the most generous TL estimates put vital Star Trek technologies [transporters, replicators, tractor beams, etc.] at beyond what the Imperium will ever achieve. Simply put, they're off the table.

Tractor Beams come in at TL16 in the current High Guard, considering that TL16 planets do exist within the Imperium I don't see this as beyond what the Imperium will ever achieve. And the updated High Guard brings in repulsor bays which can be reversed to act as tractor beams at TL13 (for a large bay).

 

[Sigtrygg]

You are bringing back repulsor bays - I could kiss you

 

[AndrewW]

You are bringing back repulsor bays - I could kiss you

The Tractor Beam Bays in the current High Guard can be used as repulsors, so wouldn't really say they are being brought back, since they already exist.

 

[Condottiere]

 

[ottarrus]

Tractor Beams come in at TL16 in the current High Guard, considering that TL16 planets do exist within the Imperium I don't see this as beyond what the Imperium will ever achieve. And the updated High Guard brings in repulsor bays which can be reversed to act as tractor beams at TL13 (for a large bay).

But warp drives, transporter, replicators, etc. are all 'by-guess-and-by-golly' rated at 17-18+...
Your argument does nothing to address my point here, that being that Star Trek and Traveller technologies are like trying to compare apples to prairie oysters. They use wildly different scales of development and don't equate at all. The fact that the USS Voyager landed on a world means absolutely nothing when trying to decide if the Annic Nova can.

 

[AndrewW]

But warp drives, transporter, replicators, etc. are all 'by-guess-and-by-golly' rated at 17-18+...
Your argument does nothing to address my point here, that being that Star Trek and Traveller technologies are like trying to compare apples to prairie oysters.

I didn't disagree with that, just that all of the technology is out of reach of the Imperium.

 

[phavoc]

The Tractor Beam Bays in the current High Guard can be used as repulsors, so wouldn't really say they are being brought back, since they already exist.

So the tractor beams have been combined with repulsors? They originally were, I believe, two separate systems.

Someone mentioned Star Trek t3ch, and tractor/repulsors were the specialized weapons of the Andromedans.

 

[AndrewW]

So the tractor beams have been combined with repulsors? They originally were, I believe, two separate systems.

2nd edition High Guard (page: 69):

Tractor Beam: In some universes, these bays are called repulsors, dependant on the primary tactical doctrine in which they are used – a tractor beam locks onto an object (such as a ship) and holds it fast or pulls it inward, but a simple change of polarity will push the object away instead.

 

[Garran]

The problem with labeling most of the Star Trek ones as "dispersed" is that dispersed also results in a reduction of hull points; since they're meant to be combat-capable (if not primarily about combat capability), that wouldn't make much sense as a design standard. Standard-Hull is more likely in a gameplay sense, which still means that they aren't going to handle well in an atmosphere but they can still cope with one. (The other problem here is that Trek presumes a lot of tech that Traveller doesn't, which means that the shape may not matter nearly as much when it comes to handling.)

Voyager, IIRC, was explicitly designed to be able to land and does so in some episodes, so it probably counts as Streamlined.

 

[Arkathan]

But warp drives, transporter, replicators, etc. are all 'by-guess-and-by-golly' rated at 17-18+...
Your argument does nothing to address my point here, that being that Star Trek and Traveller technologies are like trying to compare apples to prairie oysters. They use wildly different scales of development and don't equate at all. The fact that the USS Voyager landed on a world means absolutely nothing when trying to decide if the Annic Nova can.

Incorrect.
The argument that USS Voyager or a Connie, while the secondary hull has no landing gear, is not a dispersed structure, like the Annic Nova, and therefore CAN operate in an atmosphere without breaking up, is. Which was much of the point being argued with Star Trek tech.