Traveller: Warships of Babylon 5

[pasuuli]

To put those flight durations into context, it would take 4 hours to get from Earth to the Moon at a constant 1G acceleration for 2 hours, turnover and a 1G deceleration for 2 hours. All the ships can handle that, most at least twice over. But it'd take 1.45 days to get from Earth to Venus, or 6.4 days to get to Jupiter - the site of the only jump gate in the Sol system, and well outside the endurance of any of these ships - or indeed the Olympus Corvette as depicted in Universe of B5! In fact, A ship would need to somehow carry 384% of its' own mass in fuel to make the trip at 1G...

I'll post more on this later, but for now, bed calls.

So what I'm hearing is that these craft would be planet-bound when translated into the Babylon 5 world... good for a trip to anywhere on the planet or in its orbit, but little else? And the larger ships can run between planets, but they're probably not accelerating all the way, so their trip time is measured in weeks.

Alternately, these ships may carry a large amount of drop-tanks. A bulky and unappealing solution.

Is this how Babylon 5 treats its ships? (I never paid that much attention). Surely, though, long-range cruisers needed more than a few hours' acceleration. (Or did they?)

 

[MongooseMatt]

There is not a great deal of long-ranged real space travel in B5, remember - when the Army of Light attacked Earth, they jumped from Mars, rather than just hit the thrusters. . .

 

[tneva82]

There is not a great deal of long-ranged real space travel in B5, remember - when the Army of Light attacked Earth, they jumped from Mars, rather than just hit the thrusters. . .

Well. They were warships with jump engines ;-)

Civilian ship going from Earth to say Babylon 5 however needs to go from Earth to Io with conventional thrusters...For example all those freighters, passenger liners etc.

 

[Lorcan Nagle]

JMS was understandably reluctant to put B5's tech into real world terms. In the Gathering, there's a line about how it'll take a few hours for Kosh's ship to decelerate from the Jump Gate to B5 - assuming a 1G deceleration curve that means the point is as much as 200,000 kilometres from the station, but that's not really borne out by events later in the series - Severed Dreams and the Series 5 episode where the Centauri send a suicide attack against the station both suggest the Jump Gate is much closer to B5.

The issue is less a situation like B5 where in a worst case scenario the ship has enough fuel to accelerate to the jump point with a relative speed of maybe 60,000 km/h and enter the point, coast along the hyperspace beacon using small amounts of fuel to correct the course and then come out at the destination jump gate and decelerate to a relative rest.

The problem becomes sytems like Sol where the Jump Gate is so far out from the inhabited worlds for security reasons - there's no practical way for a non-jump capable ship using reaction drives to make the transit from Jupiter to Earth. Given that EarthForce have strict restrictions on unauthorised use of Jump Drives in the Sol system, this gives three options for commercial traffic.

One is that there's a series of refuelling points dotted in space - highly impractical as you'd have to cover enough points (or have them orbitting as well) that any ship making the journey will encounter enough of them despite the relative position of Earth/Mars and Jupiter at the time - and any ship that uses such a fuel dump would have to decelerate to a relative stop to use it anyway.

The second is that a jump-capable Earthforce vessel escorts the civillian vessels in, using its' jump drive to bring them in closer.

The Third is that civillian traffic can't travel further in-system and any shipments are delivered to the Transfer point at Io, wherein it's loaded onto authorised bulk haulers that travel insystem via jump drive. This is refuted by the episode "Racing Mars", where we see an Asimov class liner on final approach to Mars.

The other problem is that military vessels are in just as bad a supply situation. With fuel usage as it is, the Olympus Corvette can't operate away from a supply base for more than a few days - and that's assuming it leaves its' engines off for most of that! It's not a huge problem for the EA, who have a lot of jump capable vessels, but a lot of the minor races don't.

A simple fix would be to do something like BattleTech, where large ships have an economical fuel usage mode allowing them a consistent 1G thrust for large periods of time, but a combat usage moe where fuel is used up much more quickly.

 

[tneva82]

and the Series 5 episode where the Centauri send a suicide attack against the station both suggest the Jump Gate is much closer to B5.

What's in that episode that hints so? The suicide attack didn't involve station at all. It was simply attack against _the gate_. Gate can be 1 hour or 1 year from station for all that attack cares. Get inside gate, blow up, gate destroyed, mission accomplished.

Point wasn't to damage the station or attack the station but blow up the gate itself.

 

[Lorcan Nagle]

and the Series 5 episode where the Centauri send a suicide attack against the station both suggest the Jump Gate is much closer to B5.

What's in that episode that hints so? The suicide attack didn't involve station at all. It was simply attack against _the gate_. Gate can be 1 hour or 1 year from station for all that attack cares. Get inside gate, blow up, gate destroyed, mission accomplished.

Point wasn't to damage the station or attack the station but blow up the gate itself.

IIRC the blast that exited the jumpgate was enough to make B5 shake

 

[Rikki Tikki Traveller]

I don't think that B5 ships operate under constant acceleration though.

In Babylon Squared, the ships took 3 hours to reach the location of B4, but they spent most of that time coasting (they were in Zero-G).

In the episode where Stephen and Marcus are travelling to Mars, they are on a cargo ship that is in Zero-G. Again indicating that they are coasting for at least part of their trip.

So, for an Earth-Io run, a ship accelerates for 2-3 hours at 1g and then coasts the rest of the way with a few hours of deceleration once they get into Jupiter space.

The travel times would be very long (weeks I think) though.

 

[Lorcan Nagle]

That's at least partially confirmed by JMS. The following quote comes from the Lurker's Guide page for The Gathering, where the time it took for Kosh's ship to get to B5 from the Jump Gate was being discussed.

The one thing to remember is that travel in hyperspace isn't the main problem; the real problem, time-wise, is the period required to get from a world to its nearest jump gate. It might take 4 days to travel from World X to the gate, and 1 day to B5 in hyperspace...while another race, 1 day from the gate, and 1 day to B5 in hyperspace, only has 2 travel days.

If we take one of the ships with roughly 10 hours of fuel for 1G thrust aboard, that means that allowing for course correction and emergencies, you've got maybe 4-4.5 hours of thust for acceleration, and the same again for deceleration, so you're definately looking at a transit time of weeks-months to get to the middle-outer edges of a solar system, which is fairly prohibitive in terms of commercial traffic. It also means that long-range military patrols are very limited, and a lot of non-jump capable warships in B5 are fluffed as being designed to perform patrol duties.

If course, this is just an issue for Reaction Drives - the two civillian cargo ships statted in Universe of B5 appear to have grav drives (and jump drives too, for that matter)


I'm all the more interested in Warships of B5 now, just to see how much space is devoted to fuel in ships with both Reaction and jump drives... Imagine what the Omega or Poseidon will look like!

 

[Dave Chase]

IIRC the blast that exited the jumpgate was enough to make B5 shake

JMS is also know for answering the question of 'how fast is travel in Jump Space?' with 'the speed of the plot.' It was one of the reasons they left the specifics out of how long exactly it took to travel in Jump Space.


As for the 'shaking' of B5 from the blast. Lets see, super big warship loaded with lots of explosives going bang in a funnel (tube).

Large amout of focusing here with enegry and 'debris' flying in the direction of the focus.

Dave Chase

 

[Da Boss]

There is not a great deal of long-ranged real space travel in B5, remember - when the Army of Light attacked Earth, they jumped from Mars, rather than just hit the thrusters. . .

Don't the Star Furies from B5 range quite far from the station - both via Jump Gate and then on patrol. Seem to remember them talking about several hours worth of travel time between gates?

 

[Lorcan Nagle]

IIRC the blast that exited the jumpgate was enough to make B5 shake

JMS is also know for answering the question of 'how fast is travel in Jump Space?' with 'the speed of the plot.' It was one of the reasons they left the specifics out of how long exactly it took to travel in Jump Space.

Like I said upthread, I understand why JMS didn't go into numbers - it gets in the way of storytelling in a dramatic TV series, and the Battlestar Galactica remake shied away from numbers for the same reason. But when you're working out stuff for a fairly detail-heavy RPG the circumstances change.

As for the 'shaking' of B5 from the blast. Lets see, super big warship loaded with lots of explosives going bang in a funnel (tube).

Large amout of focusing here with enegry and 'debris' flying in the direction of the focus.

We're getting somewhat sidetracked from the reason I brought up that episode in the first place - to cite that for one reason or another JMS decided that the jump gate should be closer to B5 than it was in the pilot.

From a science side of things though, focus or no, it'd have to be one heck of a big explosion to have had any kind of effect on B5 if the gate was as far away as the pilot suggests- vaccum is a terrible conductor and pretty much any non-kinetic energy dissipates fast. An explosion does most of its' damage from the expanding wave of sheer heat, and the atmospheric shockwave it causes. In sapce the heat dissipates fast and there is no shockwave - leaving only the debris field as a threat to anything.

 

[pasuuli]

type Type S scout
tonnage 100
thrust 2
duration 8.8
fuel % 0.44
fuel tonnage 44

You mean fuel = 44%, right? Not fuel = 0.44%.

Because fuel = 0.44% is very light, and allows starships to be very interplanetary.

And if Matt said that B5 says that interplanetary travel is s l o w, then you probably DO mean 44%.

I've never thought about what it should be. 4 hours of 2G isn't very much, tho.

2 hours at 2G's => 1 AU every 3 weeks.

So that shuttle to Mars, at the best possible location, would take a couple weeks each way. At opposition, it could take over 3 months?

Alright, I think I can actually believe that.

And even so, that's still a lot of fuel.

It's not that I'm against lots of fuel -- I played a lot of Traveller -- it's just that I didn't picture Babylon 5 ships as using a lot of fuel -- for example, the Starfury, or the Agamemnon. I have to get used to the idea.

Which supplement has the B5 shipbuilding addenda? B5 Universe?

 

[Lorcan Nagle]

it is indeed 44%, I quickly ran the numbers in Excel the other night, hence the formatting hiccup.

Universe of B5 says to use High Guard with some modifications which are listed in the book, but fuel requirements remain the same.

Other things to consider for small traveller craft converted to reaction drives to use in B5 - the effects of microgravity on a person would have to be looked at for any long-term transit, certainly the apparent slow crawl across a solar system. A chunk of ship's space will need to be given over to exercise equipment to prevent muscle atrophy in the crew and passengers.

Also, you'd have to look at having enough supplies on board, obviously.

 

[lastbesthope]

In sapce the heat dissipates fast and there is no shockwave - leaving only the debris field as a threat to anything.

There would be a small shockwave from the expanding cloud of formerly ship contained atmosphere, very small but present.

LBH

 

[Traveller-61]

Well the book arrived in the post this afternoon and first impressions - very good!
The plans are clear, although I will need a magnifying glass to get some of the detail. Some of the weapon loadouts confused me a bit (e.g. 6x Heavy Laser Cannon on the Hyperion - I would have thought 4 absolute max) but I guess that is the price of making it fit the Traveller rules. Interestingly the deck plans of the Hyperion do not match the old Mongoose plans, oh well, obviously two different marks of ship :lol:

Now I would have said the selection of ships was good but ... where are the ISA??? :shock: No Victory, No Whitestar, No Lilandra etc

Matt himself posted that the Whitestar would be in there and in the advert on the Mongoose site (and the back of the book itself) I quote "From the humble Hermes to the mighty Victory-class advanced destroyer,"
Well, the Hermes is there ... where is the Victory?!

I am disappointed especially as I was going to set a game on a Victory class ship; not that I regret buying the book, I just wish it had included a few more ships (as promised).

DW

 

[tneva82]

Now I would have said the selection of ships was good but ... where are the ISA??? :shock: No Victory, No Whitestar, No Lilandra etc

That's just bizare. Hopefully it's just editing error and they will atleast provide them in PDF(maybe free PDF book with them in it like they did with Universe of B5).

 

[lastbesthope]

Now I would have said the selection of ships was good but ... where are the ISA??? :shock: No Victory, No Whitestar, No Lilandra etc

That's just bizare. Hopefully it's just editing error and they will atleast provide them in PDF(maybe free PDF book with them in it like they did with Universe of B5).

I blooming hope so, that is a shocking omission, but please tell me at least that the Sharlin is in there.

LBH

 

[lastbesthope]

Just checked the Planet Mongoose post from back in Feb, both the WS and VCD are listed there as being in the book.

Emailed Matt to see what he says.

LBH

 

[Valarian]

The Victory, at least, should be there according to the blurb for the book listed on the store side of the website.

From the humble Hermes to the mighty Victory-class advanced destroyer ...

 

[Traveller-61]

I blooming hope so, that is a shocking omission, but please tell me at least that the Sharlin is in there.

LBH

Don't worry LBH - the Sharlin is there
(Along with a Tigara, Torotha and a very large [2 pilots + 4 passengers :shock: ] Combat Flyer)

DW