Canonically .... they use x-boat routes because, canonically, travel at J-4 is only possible along x-boats routes for "commercial" enterprises (read as megacorp). Must be for insurance reasons
T5 Only: Liberty Ship Development Discussion
- Thread starter Major B
- Start date
Canonically .... they use x-boat routes because, canonically, travel at J-4 is only possible along x-boats routes for "commercial" enterprises (read as megacorp). Must be for insurance reasons
Using the 2000Td Bk2 designs, it's actually reasonable to go J3 - cost per ton per jump is (1E) Cr1,333.8 (2E) Cr1548.9... about half the cost of 3J1, and still less than 1J2 + 1J1.
5000 Td J2 is (1E) Cr780.8 (2E) Cr794 per ton. So, it's actually practical for them to charge Cr1000/ton... for a J2...
See, there are economies of scale involved. Namely, the 20Td bridge and the badly broken Bk2 PP formula.
Consider the canonical 30-dton cargo module designed to fit into a cutter.
This module contains many more of either the 20' or even 40' containers.
Each dton = 14m^3 or about 495 cf. Each 1 m^3 effectively equaling 1,000 kg or one metric ton(ne).
Major B
SOC-14 1K
Engineering update
I can't provide much in the way of progress but I can relate that I have found developing subhulls a better way of developing the design than trying to design the ship as a whole.
Really it is a balance because when it comes to engineering I have calculated out the main hull requirements and then, because of the way I figured those out, I have found it pretty simple to translate that back into subhulls.
Here is an example of the coincidentally easy division work:
The entire ship needs a Z7 Jump Drive and Z7 Power plant to produce J3 and P3. A single J-Drive Z displaces 125 tons so the total will be 875 tons. ACS rules tell you to put the J-Drive into location 0 (center of the ship) if it is a jump bubble but I thought that I could spread the 7 individual drive units along the spine of the main hull (which happens to be 7 subhulls long). So the 7 main hull sections ending in 4 each will mount a 125-ton J-Drive Z. I think that this would produce a string of connected jump bubbles rather than one big one but I'm not sure about that.
I can also mount the Z7 P-Plant in the same compartment as the jump drives, which makes sense because they have to burn the fuel for the J-Drive. Each Modified P-Plant displaces 36.5 tons. Add that to the 125 ton J-Drive and you have 161.5 tons of drives and 38.5 tons leftover for controls and other stuff in each of the 7 compartments.
Here is some more fortuitous math. The main hull only holds enough fuel for J1 (1120 tons). Fuel for a J2 or J3 must be carried in subhulls so longer jumps restrict cargo capacity. Divide the fuel for 1 parsec (1120 tons) by six and you get 186.67. Round that up to 187 and it only takes six subhulls to provide an additional parsec of range.
That actually works out perfectly because you need two tons for fuel transfer pumps and 8 tons for grapples. That leaves three tons in a 200-ton subhull for other purposes. One possible way to use that space would be to divide each of the two hardpoints into firmpoints and allocate a half ton for a defensive weapon to be mounted in each firmpoint. I am thinking a single beam laser per firmpoint used primarily for point defense against missiles.
I am thinking that I will use the twelve outboard subhulls (locations 3 and 6) as the fuel pods.
One more math update. I discovered that the Modified TL 11 Maneuver Drive will push the 4000-ton main hull (alone with no attached subhulls) at 3G so maybe a braced cluster hull is worth the added expense. You can add 10 subhulls to the main hull and still make 2G acceleration but anything more drops performance down to 1G.
Thats all for tonight. More to follow in a day or two.
I can't provide much in the way of progress but I can relate that I have found developing subhulls a better way of developing the design than trying to design the ship as a whole.
Really it is a balance because when it comes to engineering I have calculated out the main hull requirements and then, because of the way I figured those out, I have found it pretty simple to translate that back into subhulls.
Here is an example of the coincidentally easy division work:
The entire ship needs a Z7 Jump Drive and Z7 Power plant to produce J3 and P3. A single J-Drive Z displaces 125 tons so the total will be 875 tons. ACS rules tell you to put the J-Drive into location 0 (center of the ship) if it is a jump bubble but I thought that I could spread the 7 individual drive units along the spine of the main hull (which happens to be 7 subhulls long). So the 7 main hull sections ending in 4 each will mount a 125-ton J-Drive Z. I think that this would produce a string of connected jump bubbles rather than one big one but I'm not sure about that.
I can also mount the Z7 P-Plant in the same compartment as the jump drives, which makes sense because they have to burn the fuel for the J-Drive. Each Modified P-Plant displaces 36.5 tons. Add that to the 125 ton J-Drive and you have 161.5 tons of drives and 38.5 tons leftover for controls and other stuff in each of the 7 compartments.
Here is some more fortuitous math. The main hull only holds enough fuel for J1 (1120 tons). Fuel for a J2 or J3 must be carried in subhulls so longer jumps restrict cargo capacity. Divide the fuel for 1 parsec (1120 tons) by six and you get 186.67. Round that up to 187 and it only takes six subhulls to provide an additional parsec of range.
That actually works out perfectly because you need two tons for fuel transfer pumps and 8 tons for grapples. That leaves three tons in a 200-ton subhull for other purposes. One possible way to use that space would be to divide each of the two hardpoints into firmpoints and allocate a half ton for a defensive weapon to be mounted in each firmpoint. I am thinking a single beam laser per firmpoint used primarily for point defense against missiles.
I am thinking that I will use the twelve outboard subhulls (locations 3 and 6) as the fuel pods.
One more math update. I discovered that the Modified TL 11 Maneuver Drive will push the 4000-ton main hull (alone with no attached subhulls) at 3G so maybe a braced cluster hull is worth the added expense. You can add 10 subhulls to the main hull and still make 2G acceleration but anything more drops performance down to 1G.
Thats all for tonight. More to follow in a day or two.
mike wightman
SOC-14 10K
The x-boat routes were established on top of trade routes already in existence for the most part.Canonically .... they use x-boat routes because, canonically, travel at J-4 is only possible along x-boats routes for "commercial" enterprises (read as megacorp). Must be for insurance reasons
kilemall
SOC-14 5K
Only problem is those things are big, a bit larger then I think a grav truck would easily navigate a city, and the 5/10 ton ones of course neatly fit into most of the shipping/trading subsystems.
Also, most of those are pictured as being round. Problem setting them on the ground, much less stacking them.
No reason though for perhaps expeditionary forces not to use on that form factor for big items- heavy equipment, large supply lots, fuel, command facilities etc.
It is more economical to use J3 rather than multiple subjumps on a J-3 route. The demonstration have been made often and is not challenged. I respectfully believe that the current issue is the "universal" design. Using a J-3 ship on a J-2 route (added capital cost, less for integral +1J jump fuel tanks) is counterproductive. Use of external/demountable fuel tanks solve the fuel space problem, but not the capital cost issue. Unless there is a form of subsidies (or Imperial order) there no eason for a megacorp to purchase uselessly expensive ships. The US oïl co., without subsidies, built slow tankers while the Japanes, with subsidies, built fast ones. The Mega Corp are unlikely to says "lets reduce our peacetime profit to make it easier for our ships to be drafted in wartime".
Id be willing to buy engineering "waste space" (fit J2 PP and drive in standard hull J3 space) if I have to run a J2 route.
The idea to have G3 braced hull make sense if you intend to have ships design as potential fleet aux to start with. For Convoy Mule, commercially viable in peace time with minimum subsidies, not sure (unless cost difference is subsidized, of course). With G-3, J-3, competing against Config 7, G-1, on J-1, J-2 routes, we are then getting into the C-2, C-3 projects range/purpose of the USMarCom, (37-41) not the EC2. And yes, you may still call them Liberty (just too sexy and cannonical), just be clear that those are not EC to avoid misunderstanding.
have fun
Selandia
I wasn't suggesting the modular container as a planetary solution but to consider a design that allowed for your 6 "Imperial Standard" (40' shipping containers of 5 dton each) or 12 "Imperial Short" (20' at 2 1/2 dton each) to fit into a module that is easily transported to the surface by a cutter. Therefore, your cargo hold allocations may want to be factors of 30 dton.
This design allows for 6 grav-flatbeds to move the cargo onward once downloaded at the destination starport or naval base.
It is your choice of course, but the intent of your "Liberty" design, as you stated, was to rapidly integrate existing designs systems into a build that allowed for support of a massive buildout.
The controlling verb in that statement is the past continuous form - were established - meaning in the past and no longer existing. The canonical x-boat routes we use in T5 do not follow the "large/great/super/immense" trade routes that exist in the "current" T5 universe. Similarly, we don't have to follow the J-4 x-boat route constraint unless I missed an entry in the BBB.
While sure this concept is also used in the Imperium, I'd see them more like the Ro-Ro ships tan the Liberty ones...
Last edited:
kilemall
SOC-14 5K
ER, I was making an offhand comment about a IMTU/possible ATU standardized container sizing, this Liberty ship baby is not my design, or design goal.
My main approach would be to tackle it from the .3-.5 time and cost factor for wartime expedience, not a permanent merchant marine or inherently economical long term ship design.
Major B
SOC-14 1K
Automation
I am working on more of the design and have a question -
In the time frame of the original design, would you expect to see a tendency toward more automation or more crew?
With losses of ship crews there would be fewer trained personnel around so I have been trying to make critical functions more likely to be successful - such as using antenna mounts rather than surface mounts for sensors. My reasoning there is that the +1 mod of the antenna is worth the 1 ton for the mount. But now I am to the point of trying to figure out controls and manning and I am wondering if the MCr and volume costs for automation outweigh the savings in crew space.
I don't have exact figures to share so I am asking for what everyone thinks the original design team's directors would have thought about decisions like gunners and engineers versus computer-directed weaponry and drives.
Some considerations:
Computers have a significant up-front cost and limited span of control. A model 0/bis computer can control only one weapon or battery at a cost of MCr 0.5. A model 1/bis can control two weapons but costs MCr 3.0. A 2/bis 3 weapons for MCr 7.5.
A bunch of 0/bis computers all networked to a 3/bis main is possible but keep in mind that each 0/bis still takes a half ton of volume and the console that links the control panel to the computer takes up at least another half ton. A sophont gunner will need more space but has no up front costs during construction.
Thoughts?
I am working on more of the design and have a question -
In the time frame of the original design, would you expect to see a tendency toward more automation or more crew?
With losses of ship crews there would be fewer trained personnel around so I have been trying to make critical functions more likely to be successful - such as using antenna mounts rather than surface mounts for sensors. My reasoning there is that the +1 mod of the antenna is worth the 1 ton for the mount. But now I am to the point of trying to figure out controls and manning and I am wondering if the MCr and volume costs for automation outweigh the savings in crew space.
I don't have exact figures to share so I am asking for what everyone thinks the original design team's directors would have thought about decisions like gunners and engineers versus computer-directed weaponry and drives.
Some considerations:
Computers have a significant up-front cost and limited span of control. A model 0/bis computer can control only one weapon or battery at a cost of MCr 0.5. A model 1/bis can control two weapons but costs MCr 3.0. A 2/bis 3 weapons for MCr 7.5.
A bunch of 0/bis computers all networked to a 3/bis main is possible but keep in mind that each 0/bis still takes a half ton of volume and the console that links the control panel to the computer takes up at least another half ton. A sophont gunner will need more space but has no up front costs during construction.
Thoughts?
Automation will be the cost of the automated systems up front, and the amount of annual upkeep-maintenance necessary over the life of the ship. But each crewman will draw a regular monthly salary for as long as the ship is in operation.
From that angle, what will be the greater financial impact over the lifetime of the ship in service?
high population polities will push very hard for more crew. high tech polities will gravitate towards automation. polities that have experienced large automated ships crashing into populated areas or into capital ships will legally mandate maximum crew for any ship that might ever approach a populated area or another ship regardless of any automation technology available. crews can handle damage control and maintenance and repairs far far better than any level of automation - damage control considerations will be prominent in vessels experiencing combat, maintenance considerations will be prominent in long-range detached-duty vessels, repair considerations will be prominent in older vessels.
I might suggest compromise. each crewman may be accompanied by a robot assistant or be in total man-in-the-loop control of fully-visible and discreet automation sequences.
mike wightman
SOC-14 10K
It has long been my contention that crew requirements on ships are already so low because of the extensive automation. Every device and system on a TL9+ ship is 'smart' and even of the main computer isn't sentient it is still a very capable AI as we understand the term in today's computer jargon..
kilemall
SOC-14 5K
I always figured the 10% ship of the LBB2 Type A bridge was due to even more extensive automation, a 'flies itself' sort of experience which is why it doesn't need much crew.
The extra 10% of that on a Type S I attribute to the better sensors, or at least heavily automated/optimized.
If a 100 t Scout can be handled by a single person, that means that starship automation is at a "robot ship" level. The Scout is basically waiting for an alarm to call the Scout's attention on a problem. A 200dt type A Free Trader use the "same" 20 dt bridge and type A drives, so why would it need a engineer or a Navigator? So why a Crew?
To figure out the number of crew needed by a ship in practical long term operations, make the Crew Bill.
It is actually the list of stations to be manned in the various circumstances that are likely to be meet, along with Who (PC or NPC) is assigned to that station.
There are two basic type of Bills: Watch keeping and Special stations
For the Watch keepiing bill, time the number of Watch.
So the Crew of the 200 dt courrier/merchant "Fair Trade" is 6
Captain, Navigator, pilot
Watch keeping pilot
Chief engineer (PoPlant and J expert)
First Watch keeper E(PoPlant and M)
Second Watch keeper E (PoPlant and Life sup) and Gunner
First Steward and medic
Jump space Watch keeping
First Watch:
Captain on bridge (monitoring systems & security)
Second Watch keeping engineer in engine
Second Watch:
Watch keeping pilot on bridge (monitoring systems & security)
Chief engineer watch keeping in engine room
Day works (upon demand): Steward in passenger area
First E wakeep nursing the unused M Drive or taking over PoPlant to allow some LiSup maintenance or repairs by second wakeep
Real space Watch keeping
First Watch:
Captain on bridge, collision avoidance
First Watch keeping engineer in engine
Second Watch:
Watch keeping pilot on bridge, collision avoidance
Second watdh keeping in engine room
Day works (upon demand): Steward in passenger area
Chief nursing the unused J Drive
Harbor Watch keeping
Night:
One person on bridge monitoring security and systems
Day:
wakeep pilot on bridge monitoring security and systems while Captain works the navigation and the engineers nurse the PP as it is on both in real and jump space, so avail for maintenance only in harbor while you are plugged on harbor's Po Grid
Confine water/space (approaching dock or any tricky non combat situation )
Captain at sensor and Tac plot
Wakeep pilot at helm
Chief at Bridge Eng console
First E wakeep at M drive for emergency manual overide
Second E wakeep at PoPlant for emergency manual overide
Steward at passenger control station
General quarter (battle station)
Helm: best pilot
sensor and Tac plot: the other pilot
Guns: Second E wakeep
Engine: Chief at Bridge Eng console or Engine room/ damage control back-up
Damage control station (ship's locker): first E wakeep & Steward as medic and helper
Standing for inspection, collision station and abandon ship station should also be made
Do they still have "man overboard station" in space?
fighting ship will have various subset of the Battle station and much more sophisticated damage control stations
So a 6 person crew will contain enough people to fill every subset of the Crew Bill of the Fair Trade. You could manage it at 5 and dispense with an Eng if not gunned but if will make for more harbor maintenance time. Even if gunned you may dispense of an Eng if the first damage control call leave the eng empty and a single person is avail for manual overide in the E room at restriced space station.
The skill set may varies, of course: Steward as Gun and 2nd E wakeep as medic at battle station Chief as the M expert ... no gun...
If all maintenance is made in port, and no passenger is carried, only two (one per watch) crewmembers are needed, with pilot 1 each and sharing the 4 eng skill set between them for emergency Eng repair.
An effect of wartime shortage of qualified crew is actually an increase of crewmembers as the few jobs that can't be automated cannot relies on polyvalent long services ressources that can have all Eng specialities or Pilot+gunner+Eng+medic. In the example above, the "Fair Trade" might need 8 crewmembers.
At the same time, the repalacment of Crew by R2D2 robot will be faced by Navy's demand for the same.
Have fun
Selandia
mike wightman
SOC-14 10K
Under LBB2 rules if you build a 199t free trader it can be crewed by a single person too.
Cross the 200t line and Imperial regulations require more crew - but if you are outside the Imperium...
Cross the 200t line and Imperial regulations require more crew - but if you are outside the Imperium...
Condottiere
SOC-14 5K
That's what you have a pop up turret for, for those pencil thin margins.
