Ship Design Philosophy

[wbnc]

Starship: Torpedo Class, or Smallest Possible, Well, Cheapest Anyway

Hull
. 35 tonnes
. 12 points
. technological level nine
. self-sealing
. gravitated
. lightened hull
.. MCI 1.3125
. streamlined
.. MCI 0.2625
(snip)
MCI 12.575'325

Notes:
1. It's possible that a six tonne bridge might impose a minus one modifier on astronavigation calculations, but six tonnes is already overlarge for a fifty tonne spacecraft.
2. Jump drive is kicked into gear by the high efficiency battery.
3. Prior to jump, the jump net is ejaculated to the rear, and the fuel bladder is inflated to fill out sixty tonnes volume of gas.

Interesting way of getting around th hull size restriction of 100 tons..inflatable "dummy hull" of 65 tons and a jump net.

envisioning it looking like a large metal sphere with a network of energized nodes along its outer surface when ready to jump.

we shall dub this the SondereinsatzSpringenBoot- "Kugelfisch".

 

[EldritchFire]

I keep seeing people say ships under 100dT cannot have a jump drive, but for the life of me I can't find that stated in any of the books I have—not the core book, not HG, not the CSC, etc. The only restriction I can find is that a jump drive must be at least 5dT.

Is it just an artifact of a prior edition that people assume, or am I just missing where it's stated?

 

[Jeraa]

I keep seeing people say ships under 100dT cannot have a jump drive, but for the life of me I can't find that stated in any of the books I have—not the core book, not HG, not the CSC, etc. The only restriction I can find is that a jump drive must be at least 5dT.

Is it just an artifact of a prior edition that people assume, or am I just missing where it's stated?

From a rules standpoint, any size ship can mount a jump drive. From a setting standpoint, Third Imperium ships are required to be at least 100 tons to mount a jump drive.

THe only text that even implies this is on page 4 of High Guard, with the definition of small craft. I believe the core rulebook has a similiar entry.

Small Craft: A spacecraft of less than 100 tons. Small craft are incapable of jumping to other star systems.

The book says such definitions are drawn from the Third Imperium. And do note that the definition given does not actually say small craft can't mount jump drives - it says they can't jump to another system. Nothing about in-system jumps.

And the minimum jump drive size is 10 tons, not 5. You can get it down to 7 tons with the rules for advanced technology, however.

 

[AndrewW]

Is it just an artifact of a prior edition that people assume, or am I just missing where it's stated?

OTU limitation, applies to the Third Imperium setting.

 

[Condottiere]

The smallest starship is probably thirty tonnes, but you'd need high technology variant engines, including a seven tonne jump drive.

The smallest default jump drive is ten tonnes, but higher technology levels can shrink this.

The hard hundred tonne ruling has supposedly come from high above, probably to remove the possibility of jump torpedoes, and has been reiterated again somewhere between Tee Five and Mongoose Second.

 

[wbnc]

The smallest starship is probably thirty tonnes, but you'd need high technology variant engines, including a seven tonne jump drive.

The smallest default jump drive is ten tonnes, but higher technology levels can shrink this.

The hard hundred tonne ruling has supposedly come from high above, probably to remove the possibility of jump torpedoes, and has been reiterated again somewhere between Tee Five and Mongoose Second.

Jup capable small craft are perfectly acceptable In noncanon applications.you just can't use them in a strict 3I setting. and you do not want to see the 100 ton Interstellar Jump Missiles i have scared the Bejeezus out of my players with ...

hard to stop a craft at Thrust 12 with heavy armor and 10DT warhead that is basically a chunk of nickel-iron moving at nearly 100K Kph... it mocks your puny pulse lasers.I restrained myself from making one up at sub 100 tons.

A 50-ton stealth coated jump drone that can go into close combat with an intercepting vessel to make itself an even harder target to hit, armed with a particle barbette, and carrying with a nuclear mine in its cargo hold as a warhead...seemed obscene. a dozen of them would be completely perverse.

I have a collection of 50-60-75 ton jump craft. I sort of ignored the 100 ton limit for my own use. 30 tons is doable but has very little room for more than a single stateroom and a pilot. at 50 tons you get a jump craft and can carry 50 tons of external cargo using a 10ton drive. without cargo its jump3 base due to ten-ton J-drive limit giving it enough exra horsepower to up max out a TL 12 jump limit.

but now that I think about it a 50 ton jump tug carrying 50 tons of external cargo is in fact a 100 ton vessel. making it a legit vessel since external cargo figures into jump drive and thrust calculations. so basically all you need is a bridge, a single barracks for the pilot, and the required powerplant, m-Drive, and J-Drive. Of course to make it Kosher for canon works you can't jump without the external cargo in place. but a 50-Dton jump fighter that can carry as much cargo as a small trader ...that's an attractive one man profit making machine.

a scarier option is to make the 50 ton "cargo" another 50 ton fighter. jump tug and strike fighter combo

 

[Condottiere]

That part was obvious once you thought exactly how you configured a dispersed structure.

The problem was getting a smaller actual hull, to manoeuvre in real space; the fuel bladder idea has been floating around , with a lot of different designers coming onto the idea independently, but there was no way to guarantee it's integrity in hyperspace.

That's where the jumpnet came in.

 

[EldritchFire]

I keep seeing people say ships under 100dT cannot have a jump drive, but for the life of me I can't find that stated in any of the books I have—not the core book, not HG, not the CSC, etc. The only restriction I can find is that a jump drive must be at least 5dT.

Is it just an artifact of a prior edition that people assume, or am I just missing where it's stated?

From a rules standpoint, any size ship can mount a jump drive. From a setting standpoint, Third Imperium ships are required to be at least 100 tons to mount a jump drive.

THe only text that even implies this is on page 4 of High Guard, with the definition of small craft. I believe the core rulebook has a similiar entry.

Small Craft: A spacecraft of less than 100 tons. Small craft are incapable of jumping to other star systems.

The book says such definitions are drawn from the Third Imperium. And do note that the definition given does not actually say small craft can't mount jump drives - it says they can't jump to another system. Nothing about in-system jumps.

And the minimum jump drive size is 10 tons, not 5. You can get it down to 7 tons with the rules for advanced technology, however.

It's a setting thing, then, cool.

 

[wbnc]

yep if you want Jump craft in your personal setting its cool. the rules do not preclude wedging a jump drive into the smallest hull you can fit it into, it simply sets a minimum size for the J-drive.

 

[AnotherDilbert]

The actual rule has always been clear: Small craft can't jump. Small craft are craft with a basic hull less than 100 dT. The hull does not have to be filled with anything but vacuum. A craft of 50 dT carrying 50 dT of external tanks or cargo is still a small craft and cannot jump.


The jump drive jumps a volume, not a mass. If we deliberately misunderstand the 100 dT rule to just be a volume there is no real need for any mass to fill out the 100 dT, we could just as well jump 100 dT of vacuum. In that case a small craft could spread out the jump net into space and jump together with the empty space around it, any inflatable bladders would be superfluous.

If we really want to play with words we could abuse breakaway hulls. Make a breakaway ship with a 30 dT section. That section is not a small craft, it is a part of a ship. Hence it is not forbidden to jump.

 

[Condottiere]

I rationalize it as requiring a certain volume to maintain stability, and adding it on to sub hundred tonnes is ballast.

Regarding which, what happens if the jump net deforms during the trip down the rabbit hole and changes the virtual volume? The inflated balloon is there to maintain a specific shape and volume.

And I recalculated the size of the smallest possible starship, it's twenty five tonnes, if you remove the bridge and give it a virtual crew.

 

[wbnc]

The actual rule has always been clear: Small craft can't jump. Small craft are craft with a basic hull less than 100 dT. The hull does not have to be filled with anything but vacuum. A craft of 50 dT carrying 50 dT of external tanks or cargo is still a small craft and cannot jump.


The jump drive jumps a volume, not a mass. If we deliberately misunderstand the 100 dT rule to just be a volume there is no real need for any mass to fill out the 100 dT, we could just as well jump 100 dT of vacuum. In that case a small craft could spread out the jump net into space and jump together with the empty space around it, any inflatable bladders would be superfluous.

If we really want to play with words we could abuse breakaway hulls. Make a breakaway ship with a 30 dT section. That section is not a small craft, it is a part of a ship. Hence it is not forbidden to jump.

The wording can be finessed a number of ways The spirit of the rules is pretty simple.No Jump fighters, no jump shuttles no jump pods...If it's under 100Dt it can't jump...ad I can understand the rule...At least for 3I settings. If I decide to use sub-100 jump craft I just deselect the rule...and build jump craft with a straightforward same as a starship ruleset. it just works in a simpler manner than playing word/rules games

I rationalize it as requiring a certain volume to maintain stability, and adding it on to sub hundred tonnes is ballast.

Regarding which, what happens if the jump net deforms during the trip down the rabbit hole and changes the virtual volume? The inflated balloon is there to maintain a specific shape and volume.

And I recalculated the size of the smallest possible starship, it's twenty five tonnes, if you remove the bridge and give it a virtual crew.

yeah, virtual crew reduces the need for both a bridge and a stateroom/barracks. It would be good for a distress drone, or courier pod....Or if you retain the Stateroom and have it run as an automated drone it would be a good personal transport.

 

[Condottiere]

Most commercial flightpaths would be within one parsec or so of inhabited space going systems.

So a twenty five tonne emergency jump beacon would be viable if the starship misjumped or dropped out of hyperspace for any reason, but in a empty hex.

 

[AnotherDilbert]

If I decide to use sub-100 jump craft I just deselect the rule...and build jump craft with a straightforward same as a starship ruleset. it just works in a simpler manner than playing word/rules games

I agree, if you want small ships, just disregard the 100 dT rule, no need for fanciful "finessing" of the rules.

 

[AnotherDilbert]

Regarding which, what happens if the jump net deforms during the trip down the rabbit hole and changes the virtual volume? The inflated balloon is there to maintain a specific shape and volume.

Either way it will go poof?

REQUIRED ITEMS
...
Strong Hull: The hull of a starship must not only be constructed to withstand normal space; it also must withstand the rigors of jump space...

 

[Condottiere]

We can turn the jump net into a jump windsock, which would prevent contact between the bladder and the hyperspace universe.

 

[Condottiere]

Starships: Streamlined Engineering and Hitting the Paywall

While having more than one engineer at hand might seem like a wise precaution, it might be an unnecessary strain on the bottomline for many owners of small starships.

While my personal preference is minimal capital outlay, this becomes dubious as the engineering machinery approaches thirty five tonnes, and monosupervision of the engines strains the safety margin.

The composition of the engine room for a six hundred tonnes could consist of twenty tonnes of jump drive, six tonnes of manoeuvre drives, and nine tonnes of power plant. A default technological level twelve fusion reactor would provide nearly enough power, but you save four thousand schmuckers per month, by not hiring that extra engineer, and likely having to give the first one a thousand more per month, as chief.

Shrinking the drives might cost more, and require more sophisticated maintenance, but it pays off in the long run.

 

[wbnc]

Starships: Streamlined Engineering and Hitting the Paywall

While having more than one engineer at hand might seem like a wise precaution, it might be an unnecessary strain on the bottomline for many owners of small starships.

While my personal preference is minimal capital outlay, this becomes dubious as the engineering machinery approaches thirty five tonnes, and monosupervision of the engines strains the safety margin.

The composition of the engine room for a six hundred tonnes could consist of twenty tonnes of jump drive, six tonnes of manoeuvre drives, and nine tonnes of power plant. A default technological level twelve fusion reactor would provide nearly enough power, but you save four thousand schmuckers per month, by not hiring that extra engineer, and likely having to give the first one a thousand more per month, as chief.

Shrinking the drives might cost more, and require more sophisticated maintenance, but it pays off in the long run.

An investment in 'energy efficient" might also help by further reducing the required tonnage of the power system.

I'd also tink most commercial vessels would make due with just enough power to jump, or burn their maneuver drives..Not both. It saves on reactor tonnage and manpower requirements.

Using Batteries might also be an option..Give a ship just enough direct power to use their maneuver drives, with the J-drive being powered by Batteries which are trickle charged while the ship is loading cargo or refueling. batteries ar simpler and require no additional crewmen to look after them.

 

[AndrewW]

An investment in 'energy efficient" might also help by further reducing the required tonnage of the power system.

Limits the places you can perform maintenance though.

 

[Condottiere]

As a Mercedes mechanic, I'd open up a garage in a busy but low tech starport.

Once you get to the medium sized ships, you could install thirty five tonne modules of power plants and manoeuvre drives, which can have each their own dedicated and specialized engineer. Since the reaction rockets can only be used in spurts, and assuming that the technology is mature, they might not need that many engineers to keep an eye on them.

As for jump propulsion, one hundred and five tonne modules might be large enough to minimize overhead wastage.