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Author Topic: Re: Construction of large naval vessels ... useless?  (Read 3484 times)

dirty harry

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Re: Construction of large naval vessels ... useless?
« on: 04 April 2011, 17:02:03 »
Not really. Depends on what you want the design to do and how much tonnage you are willing to put into the design.

My intention was a Missile Cruiser but not a damn missile carring Missouri battleship. It should be able to be placed close to the shore and not somewhere where only artillery or airstrikes could hit it. Therefore it should be somewhat lightweight. Thinking big is not my intention.

The amount of armour that can be bolted on to a large NSV can be staggering on the ground combat scale; HUNDREDS of points of armour per location. Considering the kind of opposition large NSV's face (generally standard-scale [medium] vehicles brought in by an invading force),this amount of armour is plenty.

That would be correct if i wanted something with about 40.000 tons upwards in mind. But those ships will need such a thick skin as they are easy to hit (-4 to hit for any attacker).
And a higher BAR rating will not generate additional armor points. It will only save your vessel from easy penetration.

Need more secondary weapons? A 10kt NSV uses template C (5 hexes long), so why not put some infantry on deck? 

And you think of this as additional weaponry? I think of Hot Shots 2...

After all i want to concrete my problems concerning these construction rules.
First of all a Litoral Combat Boat, constructed with HM Vee and using the combat vehicle rules. This is just the benchmark for the following LNV construction and not to be dissected for optimization.
  BattleTech Vehicle Technical Readout

Type/Model:    Captain Bullard LCB-2
Tech:          Inner Sphere / 3060
Config:        Surface Ship
Rules:         Level 2, Standard design

Mass:          165 tons
Power Plant:   300 Vlar XL Fusion
Cruise Speed:  21,6 km/h
Maximum Speed: 32,4 km/h
Armor Type:    Ferro-Fibrous
  2 Long Tom Artillerys
  2 LRM 10s
  1 SRM 4
  2 Streak SRM 4s
  2 ER Medium Lasers
  2 SR Torpedo 4s
  1 Beagle Active Probe
  1 Guardian ECM
Manufacturer:  (Unknown)
  Location:    (Unknown)
Communications System:  (Unknown)
Targeting & Tracking System:  (Unknown)

Type/Model:    Captain Bullard LCB-2
Mass:          165 tons

Equipment:                                 Items    Mass
Int. Struct.:  85 pts Standard               0     16,50
Engine:        300 XL Fusion                 2      9,50
Shielding & Transmission Equipment:          0      5,00
    Cruise MP:   2
     Flank MP:   3
Heat Sinks:     10 Single                    0       ,00
Cockpit & Controls:                          0      8,50
Crew: 11 Members                             0       ,00
Turret Equipment:                            0      7,00
Armor Factor:  286 pts Ferro-Fibrous         2     16,00

                          Internal    Armor
                          Structure   Value
   Front:                    17         70
   Left / Right Sides:       17      58/58
   Rear:                     17         50
   Turret:                   17         50

Weapons and Equipment    Loc  Heat  Ammo   Items    Mass
2 Long Tom Artillerys    Turret   0   50     3     70,00
1 LRM 10                 Front    0   12     2      6,00
1 LRM 10                 Rear     0   12     1      6,00
1 SRM 4                  Rear     0   25     2      3,00
2 Streak SRM 4s          Turret   0   25     3      7,00
2 ER Medium Lasers       Turret  10          2      2,00
1 SR Torpedo 4           Right    0   25     2      3,00
1 SR Torpedo 4           Left     0          1      2,00
1 Beagle Active Probe    Body     0          1      1,50
1 Guardian ECM           Body     0          1      1,50
1 C.A.S.E. Equipment     Body                1       ,50
TOTALS:                          10         23    165,00
Items & Tons Left:                          15       ,00

Calculated Factors:
Total Cost:        29.460.975 C-Bills
Battle Value 2:    1.425 (old BV = 963)
Cost per BV:       20.674,37
Weapon Value:      2.116 / 1.993 (Ratio = 1,48 / 1,40)
Damage Factors:    SRDmg = 63;  MRDmg = 40;  LRDmg = 29
BattleForce2:      MP: 2N,  Armor/Structure: 0 / 12
                   Damage PB/M/L: 7/8/5,  Overheat: 0
                   Class: NS;  Point Value: 14
                   Specials: ecm, prb, artL

If i want to copy this ships firepower into a large naval vessel, it will be the slot limitation that will handicap everything. In order to store those weapons and systems (only slot limitation!), i need a displacement of 4800 t! The LCB weighs 165t...
What are the other limitations?
Engine? No way. With only 2/3 movement i would need a steam engine with a coal supply big enough to go intercontinental to fill this weight.
As a calculation measure i took a 4/6 movement as appropriate and tested it with several engine types.
I.C.E. with a 7000 km range: 1910t
Fuel Cell with the same range: 1945t
Fission reactor: 1210t
Fusion reactor: 648t
Including the ships structure weight and the weight of the weaponry something between 1700t and 3000 tons will be left ... as storage. There isn't even a single slot for the ships mess!
Armor? Another lame joke. Doing the calculations based on the TO, you may mount 329 plates of whatever kind of BAR rated armor on the LNV. Even BAR 10 will weight negligible 18,5t. In my opinion you will never face the need to reduce your weaponry in order to find the additional armor weight. On the other hand there are 6 areas and a single turret to armor (instead of the 5 of the litoral ship). That reduces the approximated shielding of a single section to 47 points - that is even subpar to the smaller vessel and even this didn't opted for its maximum of 617 armor points. If i wished to equalize that armor protection, the whole LNV would weight 10.600 tons. And there are assault drop ships with that armor plating just in there nose section weighing less...

So, after all, i keep sticking to my opinion. Large naval vessels are extremly hampered by the construction rules.
In order to address these problems i would opt for two modifications.
1. Add more slots to the naval construction. A 12.000 ton ship shouldn't be cramped after installing just 4 Long Tom artillery pieces. Other large support vehicles might need a review, too.
2. More armor is a must. To prevent extreme large vessels from getting inpenetrable, a more complex math with a decline according to the ships total weight would fix this prob ( battle spaceship construction already presented something like this).


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Re: Construction of large naval vessels ... useless?
« Reply #1 on: 04 April 2011, 18:56:50 »
I won't go so far as to say that large naval vessel construction is useless.  It is true though that there are some problems with trying to get capabilities that are close to real warships.   There are indeed the problems with heavy ships in terms of slots.  It isn't insurmountable though.

It really does come down to the fact that the warship rules for large scale wet navy ships are difficult to get working right.  I do agree that the terms for armoring heavy naval warships is a bit...  odd.  It is difficult to really gauge what is considered 'heavily' armored because it is too easy to put on massive amounts with next to no consequence.  Try to use canon designs and you have the thinly armored hyper beasts such as the Maebh or the insane armor belt of the Luftenburg, which rivals at 100,000 tons some of the warships...  and anything that can take a 60 pt orbital capital scale weapon bay hit square to the chin and stay floating is not right.   It really is tough to judge in that regard.

The only question about designing the Littoral naval vessel in the fluffled example below the very nice small ship is what tech level is used.  I know when I was trying to get the Sovereign class stats done, I tried to say it was a higher tech ship and came up with so much extra room so lowering the tech helped fill in the holes.   It went from a tech base E warship down to a D, at which point it all slipped together right.

I think the biggest thing about designing the heavy warships is just trying to keep oneself from not going too nuts with it.

Though, I would like to say that the small warship in the example is great.
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Re: Construction of large naval vessels ... useless?
« Reply #2 on: 04 April 2011, 21:38:29 »
The thing about it is that a 165 ton combat vessel has a number of limitations in deployment and strategic use (note that I'm not commenting on any of the actual "on-paper" capabilities of the design); mainly, as a boat built under the combat vehicle rules it lacks any kind of long-term accommodation for long-term deployment (crew quarters for its crew of 11, consumable supplies, spare parts allotment...). This ties the 165 tonner to a fixed base or forces it to rely on a tender vessel of some sort (likely a large support vessel, because otherwise you are stuck at 2/3 MP tops, which is pretty useless for a combat vessel whose likely opposition is fast hovercraft.

The key about larger craft is their ability to stay on-station for long periods and their ability of installing some pretty darn big engines for higher speeds.

Not enough armour? Not that essential; swap out some of the weapons for AMS, longer-ranged weapons or other combinations to keep the bad guys away. Remember what the likely opposition is: aerospace fighters and hovercraft; for these opponents 47 points is not at all shabby; if the LNSV comes under orbital bombardmentit is toast regardless of BAR/10 armour packed.

Too much cargo for your tastes? Try using a lower tech level or adding some chassis mod.

Need more slots? make hard choices regarding armament: stuck on having two tubes? downgrade one or both to Snipers or Thumpers. Stuck on Long Toms? drop one. Combine the SRMs and LRMs into MMLs, drop the beagle (useless on either a slow boat or a large ship at sea). There are choices.

That being said, I'd love to dissect your 165-ton boat; I see things I like.  8)


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Re: Construction of large naval vessels ... useless?
« Reply #3 on: 18 April 2011, 12:47:46 »
Personally I would opt to use the mobile structure rules to build large military blue water vessels.  It will definately help out with the # of items carried issue.