Two-Part Ship Designs

[Scarecrow]

I was thinking the other day of variations on a theme - the theme in
particular being the humble Scout.

I wondered if it would be possible within the design restrictions to
make a ship in two parts. I liked the idea in Attack of the Clones of
a detachable FTL drive - on the Jedi Starfighter.

I took the Scout and assigning the absolute essentials to the FTL
hull, I think I was left with about 50 tons. This, I decided could be
a 50 ton launch or ships boat that detaches from the Jump drives and
is propelled with maneuvre drives. The bridge would be the same
bridge on both ships.

I only go that far before I realised that it would either need to
take the powerplant with it or have two powerplants. Also, if the
Jump drives were left in orbit they would require their own computer
and control system - even if it wasn't a bridge - to orbit. Neither
did I consider which part would retain staterooms and which part
cargo.

Has anything like this been done before? Is there anything shockingly
wrong with this idea?

Crow

 

[vegascat]

Leaving the jump drive in space is a way to save fuel for landings, yes, but it does add complexity to the overall design. All the connections left open to vacuum which have to be exact on hookup could lead to misjumps.
You might want to take a look at Sup 7 at the jump shuttle for the SDB.

 

[Ben W Bell]

Another problem is that yes the jump section would need a powerplant. However you don't need to power the jump drive and maneouver drives at the same time and a two part design using two power plants would actually end up being more wasteful as the power needed to power the jump grid is (in the T20 rules anyway) usually smaller than that needed for the maneouver drives.

However as mentioned by Vegascat it has been doen before as canon in Traveller on the SDB's with strap on Jump modules though I'm not sure how this works properly as some elements of the jump system still have to be installed in the non-jump section to give the jump grid and the control systems for that. Not that much I know but it would need to be accounted for and no current construction system actually provides for this matter.

 

[Rodina]

Of course, there is going to be some wasted mass in all of this, since you do need some extra redundancy. And a 100 ton ship is pretty tight as is. Maybe if you built a 150-ton jump "sled" around a modular cutter you might have something pretty functional.

 

[clair_rand]

Had a few thoughts on this a while back.. kinda taking the battle rider concept to its extreames.

Two ships.. on a large STL battleship, two thruster banks mounted on wings. which mates to a FTL transport frame, it can fight as 'one ship' if need be.

It has Jump6, 2G when docked and jump0, 6G detached (warship) and jump6, 4G (transport)

most of the systems not required for actual combat are in the secondary hull, shuttles and so forth.

never actually mapped it out fully (didn't have time) but i thought it could be worth a look.

 

[The Oz]

I recently did some playing around (in HGS, thanks Andrew!) with the same idea and made up a 100,000 dton battlerider ferried by a 150,000 dton jump shuttle. The jump shuttle had extra tonnage assigned to jump drive and powerplant to give the desired performance when both ships were joined. Together they could make Jump-4 and 1-G (this assumes that the BR maneuver drive is inoperable while the two are joined), while the BR was 6-G alone and the shuttle was Jump-6, 2-G. Since HG is mostly percentage-based for component size, I imagine those proportions would remain roughly the same no matter the size of the carried vessel, for the same performance.

In this case both were complete ships on their own, with their own bridge, computer, powerplant, etc.

Interestingly enough, six sets of BR/JS were cheaper than building a single (huge) BT to carry six of the BRs.

 

[Ran Targas]

^ I built a much smaller version for use as a privateer to include the jump shuttle having most of the cargo space so the raider wouldn't have to carry any excess weight. The performance wasn't quite up to M6/J6 but it could definitely run down a Fatty or Far Trader.

 

[Scarecrow]

WOW!

Thread resurrection! I thought this thread was dead two years since!

You might be interested to know that this thread eventually gave rise to the Rhino-Hunter

Cheers

Crow

 

[clair_rand]

thread ressurection.. that would be me, and an evening hunting through the archives.. I've not finished yet either

 

[JAFARR]

I also had ideas along this line. I once did a HG BR/Carrier which gave me 6 spinal mounts in a 300,000 tn package. With MT I played with the idea of TL 15 allowing a basic Config 7 ship which would allow using maneuver units for all carried units under co-ordernation of the carrier. I figured that maneuver drives would need double the control points to make this work. If I remember right the main BR's were just armored Spinal mounts that had 5G. There were also refueling shuttles, Troop/Cargo shuttles, and several fighter wings. Each individual unit except the small craft provided support/quarters for it's own crew. The carrier was J-5, M-1 by itself and J-2 fully loaded. It had a spinal mount to be used aginst bases and other un-maneuverable targets when the likelyhood of retaliation was negliable. Problem was I did not work out the details for the entire thing so I am not sure it could be made to work.

 

[Madarin Dude]

Rhino is quite an inspired design. I think I might work on somethign a little bigger. The idea here is to have different kinds of lower halves depending on mission. Have the J-Drive portion partially streamlined for skimming. Some loads can just be bulk cargo. But ideally is a low perfomance lander that is filled to the brim with cargo. The JH-Drive portion will of course have high performance as long as the pod or second half is not attached. The Drive portion would be like 500 ton jump 4, 4G. But with the 500 ton lander woudl be Jump 2, 2G.

 

[daibaka]

What would be really cool is a two part ship that could land a crew on a planet in system while the J-drive section went off and refuelled at the local gas giant. Preferably on its own and without supervision. (Robot brain? Or failing that, an unimportant and eminently sacrificial NPC crew member at the helm) We'll ignore for now the fact that many systems don't actually have gas giants...

 

[Zutroi]

As an exercise in frustration for a player who ran a repo, one of my friends designed a passenger liner built around a 100 ton jump-frame and 10, 30 ton cutter modules. The modules had no physical connection to the frame aside from a power coupling, they connected only to each other...

The result was a hijack-proof ship. It took the repo-man an entire extra day of planning to set up his capture of this particular skip...

 

[Golan2072]

I think that a two-part ship configuration is quite easy to do in Book 2; The same engine will have one rating for the tug alone and one rating for a tug tugging cargo. So here is my design, inspired by the Nostromo (from Alien):

TL12 Type-MT Jump Tug
The TYC MT-77a Jump Tug is the current workhorse of interstellar colonization, carrying large cargos and non-starships/stations over interstellar distances. Alone, the Jump Tug is a medium-sized ship with extremely powerful engines. When tugging cargo (up to 5.25 times it's tonnage), the Jump Tug has reduced performance. When carrying large cargos, the Jump Tug usually uses drop-tanks to carry additional fuel.

Book 2 design. Using a 800-ton non-standard streamlined hull, the Jump Tug has Jump Drive-W, Manouver Drive-w and Power Plant-W, and is capable of 5-G acceleration and 1-Jump-3. The fuel tankage of 400 tons supports the power plant and supplies some of the jump fuel (all of it if the tugged cargo is small). Adjacent to the bridge is a Model/4 computer. There are 10 staterooms. 8 Hardpoints have been designated and 8 tons have been set aside for fire control, though no turrets or weapons are installed. One standard [as seen in Book 2] Ship's Boat are carried onboard. There are 51 tons of Cargo Space. The minimum crew nesecary to operate a Jump Tug is 10: One Pilot, one Navigator (who also operates the Ship's Boat), one Medic and seven Engineers. Up to eight more Gunners will be required if turrets are installed. The Jump Tug costs MCr558.6 (including architect's fees) and takes 28 months to build.

As mentioned before, actual performance depends on cargo size. When tugging up to 200 tons of external cargo, the ship is capable of Jump-3 and 5-G. When tugging between 200 and 1,200 tons of external cargo, the Jump Tug is capable of Jump-2 and 2-G. When tugging between 1,200 and 4,200 (the maximum load) of external cargo, performance is rated at Jump-1 and 1-G.

Note: I use HG drive TL limits rather than book 3; otherwise it will mean that on MTU's TL12 there will be Jump-6 capable "small" starships, which is undesirable (as it brings the Frontier too close to Earth).