a tender topic...

[Cannonshop]

challenge: Build a vessel or combination custom jumpship/Dropship combo that is optimized to provide the following:

1. 'at sea' (in deep space) maintenance, refuel, and consumables replenishment for warships and combat dropships.
2. may not be a remodeled Lagrange.  May not exceed 250,000 tons.
3. Must have sufficient cargo fraction and personnel to provide full restock of fuel, air, food and water for six equivalent vessels simultaneously.
4. Mission duration is 48 Months.  Please stock accordingly.

Defenses: Must be lightly armed (must be armed, can't be armed heavily) with an emphasis on point defense.
Must be able to field up to three squadrons of Aerospace fighters and one squadron of armed smallcraft (vessels bigger than a fighter, and smaller than a dropship).

Must also be able to support these.

Must have a minimum of 2/3 thrust.

Nice-to-haves include Gravity decks and recreation areas for visiting crews of the vessels it's built to support.

[Vehrec]

So if it's supposed to carry supplies for 6 similar ships, for 48 months, then it needs to carry 28 years of supplies?  Or, in other words, it needs to spend 33.6% of it's cargo mass on spare parts and maintenance equipment for itself and it's tender vessels?  When restocking vessels, should replacement crew also be allocated?

If building a jumpship/dropship combo, must the 2/3 thrurst be waved for the jumpship?

[AlphaMirage]

I volunteer this Ajax Armored Transport with the Mech Bays replaced with two squadrons of Aerospace Fighters

Nike Light Jumpyard
Mass: 150,000 tons
Cost: 1,104,444,175 C-bills

Fuel: 85 tons (425)
Safe Thrust: 0
Maximum Thrust: 0
Sail Integrity: 4
KF Drive Integrity: 4
Heat Sinks: 105
Structural Integrity: 1

Armor
    Nose: 4
    Fore Sides: 4/4
    Aft Sides: 3/3
    Aft: 1

Cargo
    Bay 1:  Standard Repair Facility (Unpressurized) (100,000)1 Door   
    Bay 2:  Cargo (368.5 tons)      1 Door   

Dropship Capacity: 1
Grav Decks: 1 (120 m)
Escape Pods: 4
Life Boats: 0
Crew:  4 officers, 17 enlisted/non-rated      
Notes: Mounts 32.5 tons of standard aerospace armor.

[Cannonshop]

So if it's supposed to carry supplies for 6 similar ships, for 48 months, then it needs to carry 28 years of supplies?  Or, in other words, it needs to spend 33.6% of it's cargo mass on spare parts and maintenance equipment for itself and it's tender vessels?  When restocking vessels, should replacement crew also be allocated?

If building a jumpship/dropship combo, must the 2/3 thrurst be waved for the jumpship?

The thrust profile in the JS/DS combo applies to the custom dropships, since a standard stick-and-ball jumpship has engines that can make about .5 at best.

This is more of a "Logistics bird"  filling a role like this:

[wolfgar]

a single ship cannot meet that duration requirement. Assuming you use a single Aqueduct to continuously replenish the water on board to break for fuel and air, no, it still wont work.

[AlphaMirage]

a single ship cannot meet that duration requirement. Assuming you use a single Aqueduct to continuously replenish the water on board to break for fuel and air, no, it still wont work.

Depends on how many Warships are involved, if its mostly Combat Dropships with smallish crews you can stock enough consumables. Not for 4 years probably but certainly a long time. At least water and atmosphere can be reprocessed and fuel can be acquired (there's even rules for it, 10 tons per day as long as water is available) while underway if you have the appropriate facilities (and sufficient power, something easily done with infinite fusion). Food, Ammo, and Spare Parts will be your biggest hinderance.

[wolfgar]

as i said, its the four year operational supply that is untennable. just fuel for that long is 60k tons a more realistic idea would be a tenth of that, and a 10kton tank for refueling other ships and supplying its own fighters. One squadron of fighters and half a squadron of shuttles. full number of docking collars for its weight, (5) and shit tons of AMS. The fighters and dropships on its collars are its offensive punch. yard space, (unpressurized) for 100ktons and thats about it

[wolfgar]

at 250ktons here is what is probably the best repair tender you are going to get for your 100kton corvettes and combat dropships

Code: [Select]

XD-202-Yrd Logistics and repair tender
Mass: 250,000 tons
Technology Base: Inner Sphere (Advanced)
Introduced: 3145
Mass: 250,000
Battle Value: 5,332
Tech Rating/Availability: E/X-X-X-F
Cost: 7,937,516,800 C-bills

Fuel: 15,000 tons (37,500)
Safe Thrust: 2
Maximum Thrust: 3
Sail Integrity: 4
KF Drive Integrity: 7
Heat Sinks: 300 (600)
Structural Integrity: 15

Armor
    Nose: 9
    Fore Sides: 8/8
    Aft Sides: 6/6
    Aft: 5

Cargo
    Bay 1:  Fighter (6)             2 Doors   
    Bay 2:  Fighter (6)             2 Doors   
    Bay 3:  Small Craft (6)         2 Doors   
    Bay 4:  Cargo (Liquid) (15000.0 tons)1 Door   
    Bay 5:  Standard Repair Facility (Unpressurized) (100,000)1 Door   
    Bay 6:  Cargo (59637.484 tons)  1 Door   

Ammunition:
None

Dropship Capacity: 3
Grav Decks: 2 (95 m, 95 m)
Escape Pods: 24
Life Boats: 0
Crew:  22 officers, 104 enlisted/non-rated, 6 gunners, 54 bay personnel, 30 marines

Notes: Equipped with
    1 Communications Equipment (1 ton)
    6 MASH Equipment (1 theater)
75 tons of standard aerospace armor.

Weapons:         Capital Attack Values (Standard)
Arc (Heat)   Heat  SRV     MRV     LRV      ERV    Class       
Nose (72 Heat)
2 Laser AMS  14    1(6)    0(0)    0(0)     0(0)   AMS         
2 Laser AMS  14    1(6)    0(0)    0(0)     0(0)   AMS         
2 Laser AMS  14    1(6)    0(0)    0(0)     0(0)   AMS         
2 ER PPC     30   2(20)   2(20)   2(20)     0(0)   PPC         
FRS/FLS (102 Heat)
2 ER PPC     30   2(20)   2(20)   2(20)     0(0)   PPC         
2 Laser AMS  14    1(6)    0(0)    0(0)     0(0)   AMS         
2 Laser AMS  14    1(6)    0(0)    0(0)     0(0)   AMS         
2 Laser AMS  14    1(6)    0(0)    0(0)     0(0)   AMS         
2 ER PPC     30   2(20)   2(20)   2(20)     0(0)   PPC         
RBS/LBS (116 Heat)
2 Laser AMS  14    1(6)    0(0)    0(0)     0(0)   AMS         
2 Laser AMS  14    1(6)    0(0)    0(0)     0(0)   AMS         
2 Laser AMS  14    1(6)    0(0)    0(0)     0(0)   AMS         
2 Laser AMS  14    1(6)    0(0)    0(0)     0(0)   AMS         
2 ER PPC     30   2(20)   2(20)   2(20)     0(0)   PPC         
2 ER PPC     30   2(20)   2(20)   2(20)     0(0)   PPC         
ARS/ALS (102 Heat)
2 Laser AMS  14    1(6)    0(0)    0(0)     0(0)   AMS         
2 Laser AMS  14    1(6)    0(0)    0(0)     0(0)   AMS         
2 Laser AMS  14    1(6)    0(0)    0(0)     0(0)   AMS         
2 ER PPC     30   2(20)   2(20)   2(20)     0(0)   PPC         
2 ER PPC     30   2(20)   2(20)   2(20)     0(0)   PPC         
Aft (42 Heat)
2 Laser AMS  14    1(6)    0(0)    0(0)     0(0)   AMS         
2 Laser AMS  14    1(6)    0(0)    0(0)     0(0)   AMS         
2 Laser AMS  14    1(6)    0(0)    0(0)     0(0)   AMS         



there are some minor placement mistakes that i'll fix tomorrow, but lore wise it should be constantly attended by three mammoths, or two and a titan or other carrier type dropship for cargo capacity. at least one needs to be outfitted as a liquids carrier

[Cannonshop]

I guess it's time to answer.

YES, the requirement posted is impossible.  The IDEA is to get as close as possible to it, based on what you feel the best emphasis of what CAN be accomplished.

A lot of historical military programs start out asking for things that can't happen, or can't happen within any imaginable limitation of costs or realistic limitation of deployment (See: "Maus" superheavy tank, some of the RFP's from the early jet age, XB-70, and so on.)

Procurement organizations often ask for the ridiculously impossible (See: Steve Amaris's fascination with ultimate weapons).  The real purpose of the challenge, is to see what people can come up with, and how close they can get to the intent, because sometimes the workaround fills the role BETTER than the original specs in the RFP.

[Elmoth]

It can carry attached dropships, right? That should increase cargo capabilities.

[AlphaMirage]

It can carry attached dropships, right? That should increase cargo capabilities.

The initial spec limited total tonnage. More Dropships or a jump capable space station (which would of course not be 2/3 and super expensive)is of course the answer. That said any fusion engine could crack 10 tons of water each day as long as you have the water which is fairly abundant in space.

[idea weenie]

I'd be tempted to break the 250 kton limit, and just go with a total of 270 ktons via Merchant Jumpship with a pair of Behemoths or Behemoth-sized space station for the grav deck and repair dock.  Since it is a deep space platform, the Jumpship's lack of maneuverability is not an issue, and the OP said "Jumpship/Dropship" combo.

The Merchant Jumpships are an existing design, so crews can be found.  The Behemoth and Behemoth-sized space station are the extremely rare component, but developing these Dropships/stations will lead to a massive increase in Lyran shipping capacity.  Inbstead of needing to limit yourself to the 8500 tons of cargo using a Mule for a single Docking Collar, you can get 75 ktons of cargo using up to 2 Collars.  At minimum each Jumpship is now hauling 4* as much tonnage.

These Behemoth Drophips would also allow for a good use for Leopard Dropships.  Instead of the Leopard taking up a Dropship Docking Collar, the Leopards carry the cargo from a variety of locations on a planet, transship the cargo to the Behemoth in orbit, and return with the arriving cargo.  The Behemoth then returns to the Jumpship, taking up 1-2 collars depending on its age, and the Jumpship goes to the next system.  The Leopards allow sending cargo to multiple locations on-planet, vs a smaller Mammoth being forced to land at a single location and the cargo being sent off by train/truck/boat.

[AlphaMirage]

Leopards? I would use Buccaneers personally as they have much more cargo tonnage. Additionally the Behemoth does have 20 small craft built in that can do a similar task while in orbit (or jump into the pirate point and use them directly). I actually have the explicit logistical capacity of my Ajax in the writeup. Also the Behemoth has a quirk where it takes up 2 Jump Collars instead of one due to its bulk so you cannot fit two on a Merchant.

[idea weenie]

Leopards? I would use Buccaneers personally as they have much more cargo tonnage. Additionally the Behemoth does have 20 small craft built in that can do a similar task while in orbit (or jump into the pirate point and use them directly). I actually have the explicit logistical capacity of my Ajax in the writeup. Also the Behemoth has a quirk where it takes up 2 Jump Collars instead of one due to its bulk so you cannot fit two on a Merchant.

The Buccaneer is a nice design, I'll admit I was trying to find a use for Leopard Dropships.

The Behemoth does have its own Small Craft, but transferring 75 ktons of cargo via all Small craft is still at most 141 tons per Small Craft (200-ton craft, 3/5 thrust, 1 ton of fuel, 3 Steerage Quarters, and the rest cargo), for a minimum of 532 trips.  So all together the 20 Small Craft would need 26-27 round trips per Small Craft.  Each Leopard that has its Mech and ASF bays removed to be a cargo carrier can transfer 900 tons at a time, needing ~83 round trips.  From there, divide 83 by the number of Leopards being used for cargo transfer.

I thought the newer Behemoths only took up one Docking Collar?  Even if not, just pairing up one Merchant with one Behemoth would be decent (220 ktons), or a Merchant with a pair of Mammoths (224 ktons).  The third option would be an Invader with a trio of Mammoths (308 ktons).

[AlphaMirage]

Leopards are for tactical Battlemech deployment on the same planet. I ran the numbers for my Ajax. How quickly do you want to unload cargo? The 20 shuttles (60 tons) of my Ajax can move almost 9,000tons of container cargo ~2500km every day. You could unload the whole thing in like 3 days if you were in a great hurry and didn't mind overworking the crews (or having spare crews/maintainers or heck even shuttles on hand).

[idea weenie]

Leopards are for tactical Battlemech deployment on the same planet. I ran the numbers for my Ajax. How quickly do you want to unload cargo? The 20 shuttles (60 tons) of my Ajax can move almost 9,000tons of container cargo ~2500km every day. You could unload the whole thing in like 3 days if you were in a great hurry and didn't mind overworking the crews (or having spare crews/maintainers or heck even shuttles on hand).

I was just measuring round trips to empty the cargo, wasn't sure about the distance.

Looking at your numbers that is 9000 tons @ 2500 km for 20 craft, aka 450 tons @ 2500 km/craft, which at 60 tons per is 7.5 trips per day.  Assuming a cargo Leopard can do the same 7.5 trips per day, since the Leopard has 15* the cargo capacity it could deliver 6750 tons per day at 2500 km (assuming it can land at the same destination).  Two Leopards would be able to tranship more cargo than all 20 of the 60t cargo Small Craft working together (9000 vs 13,500).  So what the Small craft could do in 3 days, the Leopards could do in 2 days if the cargo transfer rates were constant.


In BT-reality I'd expect your idea of a conga line of Small Craft (and Dropship) cargo transports to be fairly standard.  They would be lining up at the Cargo Bay doors so the larger Dropship is constantly transferring cargo, instead of waiting for the waves of its Small Craft to return.  7.5 round trips per day = ~3 hours per round trip = ~3 hours that can be put to use loading other Small Craft instead of waiting for the first wave of 20 to return.

(This would be a good RPG idea too, where a large cargo Dropship has arrived and their local spaceport contact asks them to help unload cargo from the Dropship in orbit.  Can they sneak on board the larger Dropship to take pictures or get a data dump, then get off again?)


Overworking the crews/shuttles/cargo personnel for a cargo transfer sounds like SOP actually.  The Dropship owner wants their ship to get moving with cargo so they can keep making money, and the sooner the Dropships is unloaded/loaded the better.


Leopards as tactical Mech deployment on the same planet?  That could be fun.  A planet having multiple Leopards as large cargo transports, but your contact has managed to bribe one of the ship Captains.  So your unit is snuck onto the planet in cargo/passenger mode via a Mule Dropship, then transferred to a warehouse where they are prepped for combat.  The Mechs are then put on board the Leopard, which then drops your unit at the target location.  Your unit does what it does best, then returns to the Leopard.  The Leopard then returns your unit to a warehouse where the Mechs can be semi-repaired, before the Mechs and 50-ton Mech gantries are crated up as cargo and shipped back off the planet.  The Leopard Captain and crew is found tied up nearby so obviously they were not at fault for what happened.

[AlphaMirage]

I think the Aurora would be your cup of tea then idea weenie as it is reconfigurable so you could totally have a 'cargo' Aurora that was actually packed with active mechs but would be indistinguishable. Actually the Buccaneer was designed as a Battlemech transport before becoming a cargo carrier according to the fluff (and it explains the aggressive name for a cargo ship).

Since it takes something like 30 minutes to load the cargo (or 60 if you are unloading then reloading) you could totally sneak onboard and get some pictures before the vessel departs again. I actually had the small craft active in waves, to land, unload on land, fly up again, and get picked up the next time the dropship orbits get reloaded and fly down again the following orbit. LEO is about 2 hours per orbit

[idea weenie]

I think the Aurora would be your cup of tea then idea weenie as it is reconfigurable so you could totally have a 'cargo' Aurora that was actually packed with active mechs but would be indistinguishable. Actually the Buccaneer was designed as a Battlemech transport before becoming a cargo carrier according to the fluff (and it explains the aggressive name for a cargo ship).

Since it takes something like 30 minutes to load the cargo (or 60 if you are unloading then reloading) you could totally sneak onboard and get some pictures before the vessel departs again. I actually had the small craft active in waves, to land, unload on land, fly up again, and get picked up the next time the dropship orbits get reloaded and fly down again the following orbit. LEO is about 2 hours per orbit

You are right, the Aurora would work nicely as a rapid-refit craft used for sneaky missions like that.  Good spot there.  I'd be concerned that it is only 37.5% cargo vs a cargo Leopard being 47.3%, but that can be explained by the rapid refitting allowed.  The Aurora could be more like a Container ship than a bulk hauler, where it drops off the pods in a quarter of an hour and gets new pods with 150 tons of cargo on board.  I wonder if replacing the pod takes less time than unloading/reloading it?

Good point about the orbits.  I was mentally going with fixed location in high orbit to semi-fixed location on planetary surface, or just burning extra fuel to get to the right location.  Now I'm getting the idea of Small Craft swapping out every 2 hours.  Wave 1 is on board the Dropship and loads cargo, while Wave 2 is on the planetary surface loading cargo.  The Dropship comes by overhead, and the two sets of Small Craft swap.  Wave 1 is now on the planet unloading its cargo and being loaded with fresh, while Wave 2 is on board the Dropship unloading its cargo and receiving cargo from the Dropship.  The loading & unloading takes 1 hour total, so on a 2-hour orbit there is plenty of time to get the cargo loaded properly and safely.

Very useful math there.

[Daryk]

I'll take a swing at this one this weekend. 

[Daryk]

What I'm finding:
1) It's entirely possible to fit a 105,000 ton unpressurized repair facility on a Super Sampan Mark IV (and a small grav deck)
2) Repair facilities come with two drop collars
2a) This means it can bring two DropShips (and two Mammoths fit!)
3) Losing most of the capital weapons for the above drops the crew by 8
4) There aren't actually any rules for refueling WarShips beyond "they must dock"
5) Four years of consumables for a crew of 367 is under 2,650 tons
6) This leaves just shy of 4,000 tons of cargo for spares/ammo (aside from what you bring in the DropShips)
7) Standard Kowloon procedure includes harvesting fuel from asteroids/KBOs/the Oort cloud, so I'm not sweating that aspect

[Daryk]

By dropping back to a single ASF Squadron, I can fudge the 10% cargo fraction by counting the repair facility's tonnage...