MgT HG 2e Space Stations and Reaction Drives

[snrdg121408]

Hello all,

Looking at my MgT HG 2e PDF page 54 Step 2: Install Drives only lists Maneuver Drives which I thought met the reactionless thruster from CT, MT, TNE, T4, GT, and T20. Looking at the Space Station Construction process I'm guessing the my conclusion is out to lunch.

Is there any way that one can install a reaction drive in s space station?

If the answer is yes, can someone please provide and example?

 

[AnotherDilbert]

Basically anything that can be installed in a ship can be installed in a station:

Space stations are designed and built in the same fashion as ships, with just a few differences. Unless stated otherwise in this chapter, all rules that apply to ships also apply to space stations – in effect they are treated as large and (mostly) immobile spacecraft.

But:

Space stations are not designed to move any appreciable distance (otherwise they would be classified as ships!) and are never equipped with jump drives.

If you install regular drives, it's not a station, but a ship.

 

[Reynard]

And that's how monitors are born.

 

[Condottiere]

A spaceship can be used as a station, but not the other way round.

The chokepoint is the bridge size and cost, which is dwarfed by that of the spaceship.

Station keeping rockets should be an option, though I couldn't telling you precisely how large they are without knowing what (sub)factor manoeuvre drive zero supposedly is.

 

[phavoc]

To the point of control systems and a bridge - a station will be just as complicated as a spaceship. A station is essentially a city, so it's going to have both 'passengers' (i.e. the inhabitants) and a crew. Stations will often be much larger than ships, so their control systems and needs will be as great, or even greater due to their larger size.

I agree that the distinction is stations aren't meant to travel. For the most part they only need station keeping drives - but with their mass in potentially the millions of tons, those station keeping 'thrusters' will essentially be starship drives. In some ways there's really no difference between the station keeping drives and M-drives for ships. I just would not use reaction drives for a station of any size since the amount of fuel would be enormous, and M-drives would be far more efficient in the long run.

 

[snrdg121408]

Hello phavoc,

To the point of control systems and a bridge - a station will be just as complicated as a spaceship. A station is essentially a city, so it's going to have both 'passengers' (i.e. the inhabitants) and a crew. Stations will often be much larger than ships, so their control systems and needs will be as great, or even greater due to their larger size.

I agree that the distinction is stations aren't meant to travel. For the most part they only need station keeping drives - but with their mass in potentially the millions of tons, those station keeping 'thrusters' will essentially be starship drives. In some ways there's really no difference between the station keeping drives and M-drives for ships. I just would not use reaction drives for a station of any size since the amount of fuel would be enormous, and M-drives would be far more efficient in the long run.

Thank you for the reply.

The ISS, IIRC, does not have station keeping capability and is nudged back into proper orbit by using the supply vehicles. The supply vehicles are using, in my opinion, a type of reaction drive to make course corrections when approaching the ISS, to adjust the stations orbit when needed, and then uses them to make the corrections to return from orbit. Even the capsules used to transport the ISS crew to and from the station is using a form of reaction drive.

 

[phavoc]

Hello phavoc,

To the point of control systems and a bridge - a station will be just as complicated as a spaceship. A station is essentially a city, so it's going to have both 'passengers' (i.e. the inhabitants) and a crew. Stations will often be much larger than ships, so their control systems and needs will be as great, or even greater due to their larger size.

I agree that the distinction is stations aren't meant to travel. For the most part they only need station keeping drives - but with their mass in potentially the millions of tons, those station keeping 'thrusters' will essentially be starship drives. In some ways there's really no difference between the station keeping drives and M-drives for ships. I just would not use reaction drives for a station of any size since the amount of fuel would be enormous, and M-drives would be far more efficient in the long run.

Thank you for the reply.

The ISS, IIRC, does not have station keeping capability and is nudged back into proper orbit by using the supply vehicles. The supply vehicles are using, in my opinion, a type of reaction drive to make course corrections when approaching the ISS, to adjust the stations orbit when needed, and then uses them to make the corrections to return from orbit. Even the capsules used to transport the ISS crew to and from the station is using a form of reaction drive.

True, but that's partially by design (the original intent was that shuttles would be doing it, but nobody planned for half the fleet being destroyed during de-orbits and the fleet being retired), and partially by tech. The advent of anti-grav tech means that nobody is going to build reaction-drives for stations. They will pay to import fusion plants and anti-grav to lift the station pieces into orbit. And station keeping will be done with the same TL.

Ethiopia could build DC-3 equivalents, but they import the 787 dreamliner. Why? Because they would be fools not to. There are some exceptions where people won't or cannot import offplanet tech, but the norm will be everyone using reasonably higher-level tech for space and other needs where it makes much more sense.

 

[snrdg121408]

Hello again phavoc

Hello phavoc,

To the point of control systems and a bridge - a station will be just as complicated as a spaceship. A station is essentially a city, so it's going to have both 'passengers' (i.e. the inhabitants) and a crew. Stations will often be much larger than ships, so their control systems and needs will be as great, or even greater due to their larger size.

I agree that the distinction is stations aren't meant to travel. For the most part they only need station keeping drives - but with their mass in potentially the millions of tons, those station keeping 'thrusters' will essentially be starship drives. In some ways there's really no difference between the station keeping drives and M-drives for ships. I just would not use reaction drives for a station of any size since the amount of fuel would be enormous, and M-drives would be far more efficient in the long run.

Thank you for the reply.

The ISS, IIRC, does not have station keeping capability and is nudged back into proper orbit by using the supply vehicles. The supply vehicles are using, in my opinion, a type of reaction drive to make course corrections when approaching the ISS, to adjust the stations orbit when needed, and then uses them to make the corrections to return from orbit. Even the capsules used to transport the ISS crew to and from the station is using a form of reaction drive.

True, but that's partially by design (the original intent was that shuttles would be doing it, but nobody planned for half the fleet being destroyed during de-orbits and the fleet being retired), and partially by tech. The advent of anti-grav tech means that nobody is going to build reaction-drives for stations. They will pay to import fusion plants and anti-grav to lift the station pieces into orbit. And station keeping will be done with the same TL.

Ethiopia could build DC-3 equivalents, but they import the 787 dreamliner. Why? Because they would be fools not to. There are some exceptions where people won't or cannot import offplanet tech, but the norm will be everyone using reasonably higher-level tech for space and other needs where it makes much more sense.

Since the MgTU is big there is a chance upon finding a star system that does not have the MD drive.

 

[AnotherDilbert]

Since the MgTU is big there is a chance upon finding a star system that does not have the MD drive.

Then, by RAW, you have to fall back on:

In theory, it is possible to build a space station without a manoeuvre drive but it will require constant (perhaps monthly) corrections to its orbit by a tug or other suitable spacecraft.

 

[MongooseMatt]

Just to weigh in here...

We always considered station and ship components to be completely interchangeable. We also consider High Guard (and just about all of Traveller, for that matter) to be a toolkit, so if you want something big to have both M and J drives and call it a station, you do you!

 

[Condottiere]

But the bridges aren't, otherwise you could replace spaceships' with the cost cut down space stations' one.

It is by a factor of five, one hundred kilobux to five hundred kilobux, per hundred tonnes, not to mention volume, which matters more at the lower end.

One assumes all that extra wiring was due to the perceived difference between the two, motivation.

 

[MongooseMatt]

But the bridges aren't, otherwise you could replace spaceships' with the cost cut down space stations' one.

If your universe demands cut price bridges for ships, the Gaming Police will not be kicking your door down

 

[Condottiere]

I already figured out that loophole, without violating any ordinances.

 

[snrdg121408]

Hello AnotherDilbert,

Since the MgTU is big there is a chance upon finding a star system that does not have the MD drive.

Then, by RAW, you have to fall back on:

In theory, it is possible to build a space station without a manoeuvre drive but it will require constant (perhaps monthly) corrections to its orbit by a tug or other suitable spacecraft.

The RAW makes no sense since the maneuver drive and reaction drive both provide thrust. The only difference, in my opinion, is the "fuel" used. In the case of a maneuver drive the "fuel" is the energy provided by the power plant.

However since RAW has been cited I will drop the subject.

 

[snrdg121408]

Hello msprange and Condottiere,

Thank you both for your comments on the subject of reaction drives on space stations.

 

[phavoc]

Some of this depends on where you want to go with your station. First off, much depends on WHERE it's located. The ISS is located in a very low orbit and due to it's low altitude it actually impacts with the outer edges of the atmosphere, thus it's orbital velocity is slowed with each orbit, and by slowing it gets dragged lower into orbit. This is where it requires a boost from a ship since it has no built-in capabilities for thrust. This can be negated by placing your station in a geo-synch orbit, thus it would only need very minor station keeping thrusters (the reason why is because each time a ship docks or undocks it will minutely affect it's orbit, so you'd want some sort of thruster to counter those actions to retain the proper orbit). Other choices are going to be in the lagrange points, or further out, at say 99D to minimize the time a ship needs to travel to the planet/stations in orbit.

To the point of having a system that has no outside connectivity and no knowledge of tech (say Earth today), then sure, you are going to have to rely upon locally produced tech and system. The ISS could have it's own thruster system, it's within our tech base. It was simply left out by choice. We could have also had a fleet of space shuttles, but we do not (also due to choice, not tech).

 

[Condottiere]

https://upload.wikimedia.org/wikipedia/commons/b/b4/Comparison_satellite_navigation_orbits.svg