2300AD:Dual stutterwarp drives

[Lemnoc]

I build a ship. It has one drive that can take it up to Distance X. It has a second drive that can kick in and take it a second Distant X. Thus, the ship can go 2X the proscribed distance. Oh, and I'll bolt on a third drive.

It seems like this should be disallowed.

What's the justification to disallow it?

 

[Wil Mireu]

I build a ship. It has one drive that can take it up to Distance X. It has a second drive that can kick in and take it a second Distant X. Thus, the ship can go 2X the proscribed distance. Oh, and I'll bolt on a third drive.

It seems like this should be disallowed.

What's the justification to disallow it?

The problem is "charge buildup". The second drive still builds up charge while the first one is running, unless the second drive is completely disabled. To bring the second drive online properly requires big, expensive tools that ships don't/can't generally carry (I think those are "drive calibrators" that may be mentioned in the book). I think the Bayern had it (because it's a big ship), and there might be experimental ones available but they're not generally available.

So you can put a second drive on, but you'd still need to discharge it in a gravity well, which you'd do when you discharge the first one - in which case there's no point in having the second one there since once the first one is discharged you'll just use that again.

There are tugs that can tow a ship out to 3.85ly on their own drives, then they can turn on the towed ship's drives and calibrate them, and then the towed ship can continue another 7.7 ly and the towed ship goes back to base. That's the only way a ship can go further though (barring brown dwarfs or artificial discharging stations).

 

[drkem99]

If a stutterwarp drive is online, it will pick up the same radiation that the drives have to dump at the 7.7 ly limit whether or not they are actually propelling the ship. Thus, at 7.8 ly, all three drives on your vessel would explode, flooding the ship with lethal radiation and killing everyone.

A drive can be transported offline and brought online and calibrated in deep space (a time-consuming and technically difficult procedure.) However, the original drive cannot shed its partial radiation charge and cannot be taken offline... without exploding. It will continue to accumulate radiation after the second drive, now online, takes over. The original drive explodes at 7.8 ly, flooding the ship with lethal radiation and... you get the idea.

The one system that does work is traveling halfway with a drive offline and then bringing it online to travel the rest of the way. The original drive either must be jettisoned or a stutterwarp tug can take your ship out to the point where your ship's drive is brought on line. The tug returns home.

Tugs are the preferred method because the drives are so blasted expensive.

 

[Captain Jonah]

Going by the Old Rules.

It is possible to use tugs to cover longer distances.

A single Stutterwarp can cover no more than 7.7 LY before it needs to discharge.

A tug travels out 3.85LY carrying a heavily shielded ship, by heavily shielded I mean so that the charge that builds up from the Stutterwarp is completely insulated from the carried ship.

At the 3.85 LY point the tug separates from the carried ship, turns round and flies back to its start point to discharge.

The carried ship can then power up its own drive which made the trip so far completely shut down and then fly on 7.7 LY. It is possible for the ship to then mean up with another Tug that has come out to mean it and do a total trip of 15.4 LY.

The ship itself cannot carry use more than the one Stutterwarp because the charge builds up in the ship and not just the stutterwarp.

The tug could go out 7.7 LY and then be carried another 7.7 LY by the carried ship. Beyond this you are getting into the realms of the very very difficult as a single ship would have problems towing two other ships that were each capable of towing it in turn.

If you had huge amounts of money to throw away you could use stutterwarp sections. Use the first and then discard it, activate the second and then discard it. Very impractical unless you really had to cross that distance.

 

[Lemnoc]

The problem is "charge buildup".

Was thinking along these lines, but did not want to disallow tugs. In fact, I wanted to force the use of tugs by disallowing an alternative.

These suggestions help, thanks!

 

[middenface]

If you had huge amounts of money to throw away you could use stutterwarp sections. Use the first and then discard it, activate the second and then discard it. Very impractical unless you really had to cross that distance.

Like the Bayern...

 

[GJD]

@Captain Jonah - you can't use a tug at both ends without dumping the stutterwarp on the carried ship. 1st tug coes 3.85 Ly with ship. Brings ships SW drive online. Ship goes 7.7 LY. Second tug travels 3.5 LY out to meet it and hooks up. Ships SW is still charged up, though. If the second tug sets off with the ship in tow the ship immediately carries on building up charge, hits 7.8 LY and KABOOM horrible radiation doom.

Unless you are on an Eber ship, of course.

 

[Lemnoc]

you can't use a tug at both ends without dumping the stutterwarp on the carried ship. 1st tug coes 3.85 Ly with ship. Brings ships SW drive online. Ship goes 7.7 LY. Second tug travels 3.5 LY out to meet it and hooks up. Ships SW is still charged up, though. If the second tug sets off with the ship in tow the ship immediately carries on building up charge, hits 7.8 LY and KABOOM horrible radiation doom.

What if you completely shut down the drive and tow the final distance leg with a thousand mile cable? Is it that you cannot completely shut down a charged drive?

 

[Wil Mireu]

you can't use a tug at both ends without dumping the stutterwarp on the carried ship. 1st tug coes 3.85 Ly with ship. Brings ships SW drive online. Ship goes 7.7 LY. Second tug travels 3.5 LY out to meet it and hooks up. Ships SW is still charged up, though. If the second tug sets off with the ship in tow the ship immediately carries on building up charge, hits 7.8 LY and KABOOM horrible radiation doom.

What if you completely shut down the drive and tow the final distance leg with a thousand mile cable? Is it that you cannot completely shut down a charged drive?

Interesting idea. One possible problem would be arranging the rendezvous with the tug at the other end though (space is big after all, and ships are tiny).

A bigger problem is that even if the drive is shut down completely, the charge is still there and needs to be discharged in a gravity well. Presumably if the drive is charged, then the charge will keep building up if it continues to stutterwarp (even with a tug), and then "horrible radiation doom" ensues. (if the drive starts out being completely deactivated though, the charge doesn't build up in the first place, which is why the Tug method works at all).

I suppose that one could physically *jettison* the drive from the ship completely and continue to be pulled along safely by the second tug though... but that would be very expensive!


I guess another expensive alternative would be to make the Tug disposable. That is, the Tug tows the ship a full 7.7 ly, jettisons its fully charged drive, the crew transfer to the towed ship and brings its drive online from being fully disabled, and then the formerly-towed ship continues on with its drive for another 7.7 ly. That means leaving the Tug behind though, though the ship can potentially now tow the driveless Tug along with it (at lease the whole Tug won't have to be left behind though). That gets you 15.4 lightyears though.

 

[Lemnoc]

I do like the idea that you can't completely shut down a drive while it carries a charge. It's an explanation that definitely allows a ship and its clean, inactive drive to be towed out of a system, but limits funny hinkiness later on the trip.

I guess another expensive alternative would be to make the Tug disposable. That is, the Tug tows the ship a full 7.7 ly, jettisons its fully charged drive, the crew transfer to the towed ship and brings its drive online from being fully disabled, and then the formerly-towed ship continues on with its drive for another 7.7 ly. That means leaving the Tug behind though, though the ship can potentially now tow the driveless Tug along with it (at lease the whole Tug won't have to be left behind though). That gets you 15.4 lightyears though.

This option, though, is not much better or different than storing a second drive on a ship, completely de-powered and inactive, going 7.7. Jettisoning the first drive. Powering up the second drive. Going another 7.7

Probably cheaper this way than abandoning an entire ship in the void, or towing one the distance.

 

[Sturn]

Going by the Old Rules.

tug travels out 3.85LY carrying a heavily shielded ship....<snip>.....At the 3.85 LY point the tug separates from the carried ship, turns round and flies back to its start point to discharge.

The carried ship can then power up its own drive which made the trip so far completely shut down and then fly on 7.7 LY. It is possible for the ship to then meat up with another Tug that has come out to mean it and do a total trip of 15.4 LY.

But where did that second tug come from? This is only feasible in a place where two Arms meet. As in you are trying to bridge a gap between two areas of space already reached by normal means. It wouldn't allow you to go someplace no man has gone before, since that second tug couldn't be waiting on the other side in the first place.

 

[drkem99]

I can tell you from the previous incarnation of 2300 AD that the two-tug trick does not work unless you jettison the drive. Once a charged drive reaches the 7.7 ly limit, it cannot be taken offline or moved via stutterwarp in any way without the destruction of the drive and the release of lots of type-unspecified deadly radiation. The thousand-mile cable might save the ship and crew but won't save the drive; might as well jettison the drive and replace the thousand-mile cable with cargo.

The expense of the drives, the difficulty in bringing them online and calibrating them in deep space, and the scarcity of the key materials in their construction are key aspects of the setting and should be tinkered with at your own risk. The drive rules are designed to maintain the setting intact; that means an absolute limit on stutterwarp distance.

If you want to link two arms out-of-canon in your campaign, just add a brown dwarf or other deep-space mass to allow discharge.

 

[Captain Jonah]

Still to change the topic slightly.

One of the things towards the end of the original game was the growing understanding of just how much "Stuff" there is out there.

Brown Dwarfs were springing up like weeds as telescopes became better.

The near stars map is, erm, balanced for play rather than being 100% accurate.

Finding systems and stars that are genuinely more than 10ly from any possible gravity well deep enough to ground the Drive charge is going to very unusual. You may end up zig zagging around a bit but you should be able to get almost anywhere.

This was not added to the near stars map because the separate arms which are such a part of the Game cease to be separate arms and the Kafer/Kaefer/Kaifer/Bugs could have come towards Earth from across a wide area making defence much harder.

Still making those long runs is a relative cost. The stutterwarps cost about 1% of the cost of the ship. If you have enough need to cross those 15 LY games then several million for expendable drives becomes acceptable.

 

[drkem99]

Yep, the sky is so crowded you can't hardly swing a dead rat anymore without hitting a brown dwarf or a rogue planet. I know Colin mentioned in a couple of posts that he went around and around with that issue while writing 2300AD for Mongoose; he finally decided to keep the old Near Star Map by using the old Gliese data.

One issue with jettisoning drives is the unobtainium (tantalum, I believe) in the drive cores. It is so rare in the 2300 AD setting that it is literally the limiting factor for growth of starship fleets and the pool of stutterwarp missiles you have to use in combat. Every time you jettison a drive, that's a starship engine - potentially, an entire starship or a dozen stutterwarp missiles - you are discarding.

It explains why the use of such a technique is rare. Otherwise, you could take a dozen offline engines and use them one at a time by discarding them before each new engine is brought on line. Virtually any gap could be crossed in that fashion.

 

[Lemnoc]

I suppose one might posit that it takes a significant mass to discharge a stutterwarp drive. Planetary masses won't do, and even many brown dwarfs are of insufficient mass. Thus, while all those dark objects are there, many are not useful.

You might still discharge a drive by (very difficult, costly) artificial technical means, leaving open the possibility for a remote discharge station.

 

[GJD]

you can't use a tug at both ends without dumping the stutterwarp on the carried ship. 1st tug coes 3.85 Ly with ship. Brings ships SW drive online. Ship goes 7.7 LY. Second tug travels 3.5 LY out to meet it and hooks up. Ships SW is still charged up, though. If the second tug sets off with the ship in tow the ship immediately carries on building up charge, hits 7.8 LY and KABOOM horrible radiation doom.

What if you completely shut down the drive and tow the final distance leg with a thousand mile cable? Is it that you cannot completely shut down a charged drive?

Well, firstly the stutterwarp field probably wouldn't extend 1000miles away. The jump calculations would fail and you wouldn't go anywhere, or the cable would get snipped off short.

Secondly, any online drive, whether running or not, will pick up the gravistatic charge when it is exposed to the stutterwarp field. The only way to prevent this is to have the drive offline (and actually partially dismantled) before the start of the trip. The charge cannot be removed except in a gravitational field of greater than 0.1G. No exceptions.

Thirdly, a cable is no good for towing. Although it's called a tug. there is no physical movement - one ship is not "pulling" another. Stutterwar works by the ship blinking out of existence here, and re-appearing over there without passing through the space in between. Tugs are ships that are able to extend the stutterwarp field around two vessels.

Disposable drives have been used on one design, the Bayern exploratory ship which had four disposable drive cores to cross rifts on it's path to Pleides. It's far from common. The 7.7 LY seems to be a hard limit (unless you are an Eber...)

G