Terran Commonwealth -- Book 2 Starship Combat

[tbeard1999]

Tbeard,

I am wondering about your premise of fighters as effective ship-killing platforms. It seems that you have not taken into account the effects of the computer programs available to a large warship versus a small fighter. They change the equation.

Not really.

The most sensible small craft weapons are missiles. A fighter can carry 3 missile racks or one laser, per Book 2. I'd always choose the missiles since they are immune to computer defensive DMs. Missiles hit their target automatically if they reach the target, so computers aren't any defensive help.

And a hit on a fighter will actually do significant damage about 40% of the time. And while a drive hit will disable a drive, it will not disable its missile racks. The net result is that each fighter will require several hits on average to knock its weapons out (4 hits will knock a fighter's weapons out ~50% of the time).

On a per ton basis, it is hard for me to imagine how any starship can compete with a comparable tonnage of fighters. A standard fighter takes up 10 tons. Add 2 tons for the pilot's stateroom and 3 more tons for ordnance (not actually required by Book 2), this means that allocating 300 tons to fighters would mean that 20+ fighters would be deployed. A starship of twice that tonnage would find itself completely outgunned. Its 6 triple laser turrets (18 weapons total) would face 60 missiles per turn for 3 turns. If the starship chose to engage the fighters, it would destroy/disable only about 3-4 per turn (assuming automatic hits). In return, it would be hit by 60 missiles+51 missiles+42 missiles = 153 missiles. That's over 500 damage points on average.

Firing the lasers in an anti-missile mode doesn't help much. In that case, assuming 100% hits, the ship will shoot down about 72 missiles, and will be hit by about 108 missiles for an average of ~400 points of damage.

You can quibble about the underlying assumptions, but every reasonable scenario will have the starship taking several hundred points of damage.

Let me demonstrate:

I have a 1000 ton Bk2 Ship, the "Panhandle":
4G
No armor
It mounts 10 turrets, 6 with tri-beams and 4 with tri-missiles.
A model/6 computer loading these programs:
maneuver/evade-6 (-5 dm)
target (req)
gunner (add say DM +1)
predict-5 (DM +3)
ECM (missiles fail on 7+)
Anti-missile
Launch (req)
Multi-target-3 (engage 3 targets)

compare with your fighter, which is considerably better than the Bk2/Starter Trav fighter.

assuming still a model/1 (CPU 2 Storage 4)
loading:
m/e-5 (add say dm -2) because some maneuver program is required
launch (req for missiles)

By your first post, a comparable 1000 ton carrier can carry twelve of these little fellows. That does seem like a lot of firepower. However, read on.

Not a good assumption. My carriers are designed for very long range missions, so considerable tonnage is devoted to cargo, maintenance crews, etc. Also, my carriers are designed for use with my combat rules, which make fighters less lethal (and therefore reduce somewhat the incentive to pack as many fighters as possible into a hull).

I just ran out a Jump 1, 1000 ton carrier with 60(!) fighters.
A Jump 4 version can carry 25 fighters, which would be appropriate for a "blue water" carrier.

I disagree with your assessment of how hard it is to kill a Bk2 fighter. Please refer to Bk2, page 34, the Hit Location Table. If we assume that Drive and Weaponry hits 'kill' a fighter

There is no basis for such an assumption. A drive hit kills the drive, but not the missile launchers. And missiles can be fired in any direction.

A weapon hit kills the weapons and it only happens 16% of the time. So, on average a fighter's weapons will be killed after 4 hits about 50% of the time.

and Cabin hits are of no effect because the pilot is in a Vacc Suit, then on any roll other than 7,8 or 9 a fighter is 'killed'. That comes to 41% Cabin hits and 59% 'kill' hits. One hit kills a fighter 60% of the time.

Since this assumption is demonstrably false, and since you've assumed only 50%- of the fighters that would be typical, your analysis needs to be re-run.

And consider that on the first turn of combat, the Panhandle will be facing 25 x 3 = 75 missiles. Assuming 10 triple beam lasers and automatic hits (and ignoring targeting restrictions), Panhandle could score 30 hits per turn. This would statistically result in around 4 fighters dead. So the next turn, the fighters would launch 3 x 21 = 63 missiles. Again, Panhandle could kill around 4 fighters. The third turn, the fighters launch 51 missiles. At that point the fighters are no threat...but there are 184 missiles streaking towards it in 3 waves. Hard to see how 30 beam lasers can shoot down enough missiles to matter. And when the actual to hit probabilities and targeting restrictions are applied, Panhandle is in deep kimshi.

Actually, it looks to me like it would take 3 or 4 Panhandles to handle even a small fighter group like this.

If we build a Jump 1 or Jump 2 carrier, the battle becomes outrageously one-sided since such carriers can carry twice as many fighters.

And large ships are increasingly vulnerable to the fact that a ship has a 1/216 chance of being destroyed by any given point of damage (1/36 chance of rolling "12" for damage; 1/6 chance of rolling "6" for a critical, which results in the ship exploding). This means that 100 points of damage will destroy the largest ships ~50% of the time.

So while you can certainly define your assumptions so that fighters aren't that good, it seems clear to me that they are utterly ferocious if used sensible and in reasonable numbers.

 

[Bob Weaver]

Tbeard,
Upon re-reading the Bk2 rules, I noticed that I had always assumed that missiles had to roll a "to-hit" roll just like beams, but the rules don't read that way. My error.
My example used a 1000 tn ship with 12 fighters. That is not an assumption, I got that straight from your first post.
You assume that each missile that gets through scores maximum damage (6 on 1D). That is your assumption, but it seems far-fetched to me, more so than the warship getting 100% hits with its offensive weaponry. The Panhandle mounts Predict-3 and Gunner Interact, which gives at least a DM of +4. Not 100% hits but I'd bet a higher percentage than missiles rolling 6 damage points.
As to the offensive power of missiles, you have again ignored the ECM program, which any reasonable warship is going to have running. Each and every missile fired at the Panhandle is going to have to deal with the ECM program, which Bk2 states quite clearly will, on a roll of 7+, cause that missile to fail. So 58% of your missiles are total write-offs. And that's before the anti-missile fire kicks in.
I have a few other observations to make, but offline matters require that I stop now.

Best Regards,

Bob W.

 

[boomslang]

As to the offensive power of missiles, you have again ignored the ECM program, which any reasonable warship is going to have running. Each and every missile fired at the Panhandle is going to have to deal with the ECM program, which Bk2 states quite clearly will, on a roll of 7+, cause that missile to fail. So 58% of your missiles are total write-offs. And that's before the anti-missile fire kicks in.

Not quite; as written, ECM is all-or-nothing -- 58% of the time it stops all of the missiles in contact with the ship, 42% of the time it stops none of the missiles in contact with the ship. [DMs to that single 7+ roll at the ref's discretion; Ship Tactics begs notice here...]

Therefore, in addition to the always-handy Anti-Missile program for the ship's lasers, IMTU, I allow missiles to be launched against other missiles. Note that since missiles don't move on the turn they are launched, this is only helpful against incoming enemy missiles that are still more that one turn away from hitting. Also note that Target and Multi-Target and per-turret restrictions still apply to this scheme.

To further help defend, I note that BT mentions that the default missile is heat-seeking, and will track the hottest thing in front of it... so I also provide for IR Flare missiles (same cost & weight as offensive missiles) which may be Targeted and Launched (again, if the enemy missiles will hit on their next movement turn, you're too late) against all the missiles fired at you in one turn by one enemy vessel, the flare sacrificing itself to pull those particular missiles off of you. This further enlivens space combat, in my experience...

 

[navywarlord]

To further help defend, I note that BT mentions that the default missile is heat-seeking, and will track the hottest thing in front of it... so I also provide for IR Flare missiles (same cost & weight as offensive missiles) which may be Targeted and Launched (again, if the enemy missiles will hit on their next movement turn, you're too late) against all the missiles fired at you in one turn by one enemy vessel, the flare sacrificing itself to pull those particular missiles off of you. This further enlivens space combat, in my experience...

The Flare idea is good - I use it too

Another great effect IMTU is chaff cannisters in place of sand... Spread by a small ejection charge, these small metal foil fragments can make a 100 tn scout the size of a 1000 tn DE... Semi-active missile sensors will "see" a huge target and detonate early, away from the actual hull....

 

[dean]

Serious stuff

Ty,

I will posit that most everyone who has replied to your idea "gets" what you are saying with your core point being: "that there's no effective way for a warship to dedicate tonnage to weaponry other than by carrying fighters."

Your solution is essentially to add powerful tonnage-consuming weaponry to your LBB2 designs to allow this specific point to be addressed, a la LBB5.

I think what most other folks are attempting to do is give other possible solutions to the situation you present. It seems your system is well thought-out and you certainly defend its application robustly. However, since you didn’t actually come out and say one way or the other that you were seeking additional input (or not), folks have added their two cents with thoughtful comments about alterative ways to “skin the cat”. Again, you have remained loyal to your original design modification and rejected the various offerings unilaterally.

I myself was going to add my two credits in, except as I read through I saw you had already rejected every suggestion I would make.

A suggestion that you may want to consider for future posts: Edit your original postings such to describe your rationales why you did NOT do something – like not making carriers weakening by requiring more hanger/launch tube space – which did not fit with your original purpose.

I know a lot of folks don’t necessarily read through the entire thread before posting, and you seem unnecessarily frustrated by having to go over your rationales multiple times because people just don’t seem to “get” what you’ve said (when in reality they never read what you said in subsequent posts).

Happy Travelling,

 

[tbeard1999]

Tbeard,
Upon re-reading the Bk2 rules, I noticed that I had always assumed that missiles had to roll a "to-hit" roll just like beams, but the rules don't read that way. My error.
My example used a 1000 tn ship with 12 fighters. That is not an assumption, I got that straight from your first post.
You assume that each missile that gets through scores maximum damage (6 on 1D). That is your assumption, but it seems far-fetched to me, more so than the warship getting 100% hits with its offensive weaponry.

I don't think I did. I stated that 108 missiles would cause about 400 points of damage. The exact statistical average would be 378. The maximum damage for 108 missiles would be 648 points of damage.

I did overlook ECM; I will re-read the rules and respond accordingly.

But even if you're right that I've overstated the lethality of fighters, my original point remains -- under Book 2, the only way for ships to devote tonnage to additional firepower is by carrying fighters. (Other than the minimal 1 ton of fire control and 2 or 4 tons for a gunner). I want both carriers *and* battleships in my universe.

 

[tbeard1999]

Ty,

I will posit that most everyone who has replied to your idea "gets" what you are saying with your core point being: "that there's no effective way for a warship to dedicate tonnage to weaponry other than by carrying fighters."

I wish I could agree that everyone "gets" that point. But virtually all of the solutions proposed fail to effectively address that point. So...if they "get" my core argument, why are they proposing alternatives that do not address my core argument?

Your solution is essentially to add powerful tonnage-consuming weaponry to your LBB2 designs to allow this specific point to be addressed, a la LBB5.

Exactly. My error was in choosing similar terminology. Had I called my weapons bays "Big Damn Turrets" or somesuch, some of the more annoying digressions over surface area and the like might have been avoided.

I think what most other folks are attempting to do is give other possible solutions to the situation you present.

Maybe so, but I think that the solutions should actually address the problem I identified. And most don't.

And I'm really not interested in alternatives unless they are better than the solutions already posed.

It seems your system is well thought-out and you certainly defend its application robustly. However, since you didn’t actually come out and say one way or the other that you were seeking additional input (or not), folks have added their two cents with thoughtful comments about alterative ways to “skin the cat”. Again, you have remained loyal to your original design modification and rejected the various offerings unilaterally.

<shrug>

A fair point. I don't mind criticism, but I did go to a fair amount of effort to design the system. As anyone who's played my modern miniature wargames rules can attest, I do put a lot of effort into ensuring that the system is good before I let it out. Of course, that does not mean that my way is perfect. If I've overlooked something significant, I'll admit it and retool accordingly.

In fact, I am re-thinking my rules a bit now. I really like the look of the Space Cruiser Yamato universe and I'm cogitating on rules for Big Damn Turrets and Big Damn Weapons.

However, I'll readily admit that I lose patience with folks who ignore my responses and simply repeat themselves. I'm willing to restate something several times because things can be overlooked. However, at some point, I start suspecting that the other fellow is intentionally refusing to respond to my legitimate points. At that point, I feel no particular obligation to keep playing the game.

I myself was going to add my two credits in, except as I read through I saw you had already rejected every suggestion I would make.

Well, it wasn't personal, I promise.

A suggestion that you may want to consider for future posts: Edit your original postings such to describe your rationales why you did NOT do something – like not making carriers weakening by requiring more hanger/launch tube space – which did not fit with your original purpose.

Believe it or not, I do try to do that. But at some point, time runs out. In your example, the reason is simple -- weakening carriers does not really address my concern. I don't necessarily want to weaken carriers; I want to enable battleships. And right now, there is no way to create a true battleship in Book 2. A 5000 ton ship with 50 turrets will have thousands of tons of empty space and will be indistinguishable from a 5000 ton armed transport. That's a 15th century analogue (where there were no dedicated warships) and my campaigns are more 19th century.

I know a lot of folks don’t necessarily read through the entire thread before posting, and you seem unnecessarily frustrated by having to go over your rationales multiple times because people just don’t seem to “get” what you’ve said (when in reality they never read what you said in subsequent posts).

Happy Travelling,

Well, I appreciate the understanding. I don't mind having my game designs questioned. And I'll change my design if it's warranted. If you doubt that, go to the Fistful of TOWs yahoo group. But the flip side is that I need to be persuaded that a change is necessary.

 

[Cadithial]

Also, I use High Guard to determine crew sizes for 1000 tons+ ships, which makes crews larger. And I allocate 1 ground crew per fighter, which I think is reasonable for a military fighter in sustained operations. I may also revise the design a bit and include space for a machine shop to fabricate parts that are short supply. (My guess is that it would need to be 20+ tons to be truly useful for a carrier wing this size).

You need more than 1 ground crew per fighter, it's going to be at least 3. Some can be shared, ie: propulsion, electronics, mechanical, and weapons crew. However, each bird will need 1-2 crew chiefs to oversee everything on the fighter.

 

[BillDowns]

Sorry for the necro

But, tbeard, what did you come up with at the end?

I'm curious (yellow )

 

[tbeard1999]

But, tbeard, what did you come up with at the end?

I'm curious (yellow )

The Real World -- and the Great Mongoose Traveller Debate -- intervened so I haven't done much. I'm also curious to see what the MGT starship combat system looks like. I liked the MGT starship design system (which I'm told comes pretty much straight from T5) and it could be virtually a drop-in replacement for Book 2.

But my thinking so far leads me to these conclusions:

1. If each shot is handled discreetly, then a shift from 2d6 to 1d10 is essential for the game to be playable. This allows a large number of shots to be resolved at the same time (i.e. by rolling a handful of d10s). It also enables a far more intuitive statistical resolution system. A 5000 ton ship could have 50 triple turrets. I don't care to have to make 150 sequential 2d6 rolls. I *could* handle 150 d10 rolls (in batches of 15 dice at a time). But far better is simply multiplying the number of weapons by the hit percentage and dicing for the remainder. So I'm certain I'll stay with a single die resolution mechanic for rolling to hit and rolling damage.

2. The more I think about it, the more I think that missiles should be treated as direct fire weapons. Large ships can fire hundreds of missiles per turn and after several turns, the mechanics become unbearable. Ideally, the engagement range should somehow be determined by the number of turns that the missile can maneuver, its speed, the target's speed and the engagement aspect. This is just a shot from the hip, but assume a missile with 6G acceleration for 5 turns. Assume 1" = 1G acceleration for one turn. Such a missile could theoretically hit any target within 30 inches unless shot down. But if the shot is from behind, and the target is accelerating at 2G, the missile's range drops to 20". If the shot is head-on and the target is accelerating at 2G, then the missile's engagement range increases to 40". This gets more complex as the angle changes and the target's evasive maneuvers are taken into account. The best approach might be to simply give missiles an effective range (duration x acceleration) and halve it aginst targets with an acceleration of 4+. In any case, direct fire missiles are probably gonna be in my next draft. I'd also allow beam weapons an automatic point defense shot before impact.

3. I'm still considering eliminating weapon bays and just allowing for bigger turrets and weapons (which would consume tonnage for the associated machinery. Broadly, the classes would be "escort" class weapons (the standard CT weapons), "destroyer" class weapons, "cruiser" class weapons and capital ship class weapons.

 

[BillDowns]

I can definitely agree with your reasoning on rolling 150 2d6

Back in the beginning of this thread you were addressing fighters. What did you decide regarding these dangerous "gnats" ?

 

[tbeard1999]

I can definitely agree with your reasoning on rolling 150 2d6

Back in the beginning of this thread you were addressing fighters. What did you decide regarding these dangerous "gnats" ?

I still think that small fighters and missiles make an extremely powerful combination. In my opinion, the carrier would be the dominant combatant of the LBB universe, especially since Book 2 gives no way to devote tonnage to firepower other than by carrying fighters. And since missiles do not make a to hit role, the electronics advantage of larger, more expensive ships is irrelevant. (The ECM software does reduce the lethalisty of missile armed fighters, but I contend that they would *still* dominate combat). Fighters must also be targeted individually, which dramatically reduces a ship's ability to deal with a swarm of them.

And carriers with low jump drives can carry a staggering number of fighters.

I am actually okay with this, up to a point, because my Traveller campaign navies resemble World War II fleets. I also think that PCs have a better change against a few fighters than they would against armed starships. And finally, fighters have serious logistical considerations that might well affect a navy's decision to deploy carriers if there was a credible alternative available (which there really isn't in LBB2).

So my problem isn't really with fighters. It's with the fact that there's no way to make anything like a WWI/WWII dreadnought with the LBB2 starship design rules.

Other than (maybe) carrying better drives and (maybe) carrying better computers, a 5000 ton LBB2 dreadnought won't be any better armed than a 5000 ton armed freighter. So the presence of classic "battleships" makes little sense in LBB2 Traveller. And without analogues to "surface combatants", carriers dominate by default. That's inconsistent with the kind of campaign I want to run.

Hence my suggestions to add weapons bays to the LBB2 design system (something that I note MGT did as well). And since I was gonna go to the effort to add new systems, I decided to retool the LBB2 combat system so that it could actually accomodate larger ships without breaking.

Ideally, I want to stress the LBB2 design system as little as possible. Mainly this is so that existing LLB2 designs will be compatible (I don't want to waste time redesigning the Type S Scout for instance).

To me, this limits me to adding new components (like weapons bays or big darn turrets), and avoiding new design rules (like armor, surface area calculations for hardpoints, etc.) or changing the rules for drives, stateroom sizes, and fuel calculations.

 

[BillDowns]

Well, for what it's worth, what I did was this:

1. Added HG bays

2. Allowed HG batteries, but dynamic instead of fixed; fighters and bays can form batteries, too.

<insert> each battery requires a copy of Target in the computer

3. I did add armor, and didn't worry about pre-existing designs.

4. I restrict fighters to a target range of 3-5 (depending on my mood) range bands (10,000 km each).

5. I use HG damage tables with a modifier of USP weapon code - ship size.

6. I allow "stacked" drives.

7. I do allow multiple computers, but programs still have to fit in one computer.

That's basically it.

For what you may wish to consider....

 

[BillDowns]

Ooops

Forgot to add my LBB2 torpedoes - basically a 10 ton, 6g launch with a USP code 4 warhead, and with a Model-0 bis (2 cpu space, 1/2 the cost of a 1-bis) running "Auto/Evade" and "Homing". No personnel.

 

[tbeard1999]

Forgot to add my LBB2 torpedoes - basically a 10 ton, 6g launch with a USP code 4 warhead, and with a Model-0 bis (2 cpu space, 1/2 the cost of a 1-bis) running "Auto/Evade" and "Homing". No personnel.

No doubt, the easier approach would be to adapt High Guard. But my Commonwealth Campaign is an explicitely "Small Ship", "Proto-Traveller" campaign and at the outset I decided to stay with the LBB2 design and combat system, for reasons of nostalgia and compatibility.

In hindsight, I've expended far more effort modifying LBB2 than I would have spent using HG and simply redesigning all the standard designs. Oh well...

If I were gonna adapt High Guard for my campaign, I'd probably use it more or less straight, with a few modifications:

1. I'd use the armor fix that I posted here last year. This prevents the unreasonably hard to kill TL15 fighters.

2. I'd restrict the maximum size of ships (or drives, so that bigger ships would be slower). Alternatively, the campaign could simply assume a far smaller naval budget than HG does. In that case, huge ships would simply be unaffordable.

3. I'd see if the system could accomodate some small spinal mounts for my "micro-capital ships".

4. I suspect that the 1 bay per 1000 tons rule would be too restrictive, making analogues for "surface combatants" still too hard to create. I might modifiy that (1 per 200 tons or 1 per 500 tons perhaps).

As a referee, I've long used HG for PC starship combat (the LBB2 combat system is a wargame, not an RPG system), so the combat system is fine with me.

 

[tbeard1999]

Alternatively, the campaign could simply assume a far smaller naval budget than HG does. In that case, huge ships would simply be unaffordable.

In my campaign, this is the case. The entire Commonwealth has a population of about 500 million. Using Trillion Credit Squadron guidelines, each person spends about Cr200* per year on naval forces and the total spent on the standing fleet is about 10 times this amount (after accounting for tech levels and starport size). There are probably another 4 billion sentient lifeforms in Commonwealth space, but they are all preindustrial societies with mocroscopic GDPs (they probably add about 10Cr each to naval expenditures).

So 200 x 10 x 500 million = 1.00 trillion credits from Commonwealth planets, plus (25 x 10 x 4 billion = 0.4 trillion credits from colonies) = a fleet worth Cr1.4 trillion.

A single Tigress class 500kton battleship costs Cr453 billion. So they are clearly beyond the capability of the Commonwealth and will remain so for a very long time. The prototypical Commonwealth battleship is the 5000 ton Virginia class battleship costing about Cr3 billion each. The Commonwealth battleline consists of the following heavy combatants:

28 x Virginia class BB (5000 tons, Cr3 billion)

42 x Indefatigable class CVs (3000 tons, Cr2.3 billion)

40 x Tarawa class Marine Assault Transports (3000 tons, Cr1.5 billion)

26 x Winters class Jump Transports (4000 tons, Cr1.8 billion)

13 x Royal Oak class Fast Battleships (3000 tons, Cr1.9 billion)

Colonial fleets field an additional 26 battleships, 34 heavy carriers, and 40 assault transports. Most of these ships are old Jump-1 ships, deemed obsolete for front line service.

In addition, there are 31 5000-ton "monitors" of various classes. Monitors are Jump-1 dreadnoughts refitted with modern firepower and designed for defense of high value systems. Most are deployed in the 12 worlds of the Commonwealth Core.

The total cost of the Commonwealth battleline (including colonial ships) is about Cr650 billion, or 1.5 times the cost of a single Tigress. And this fleet is responsible for protecting an area about 2/3 the size of the Spinward Marches (~300 systems).

*The Commonwealth has a rapidly expanding, free market economy and it intentionally limits military spending to maximize economic growth. So the Commonwealth spends about half of what it normally would under Trillion Credit Squadron guidelines. Given that its main enemy has a population eight times larger, the Commonwealth must maintain a huge technological and economic edge.

 

[Golan2072]

3. Turrets

Turrets must have the same type of weapon, unless the ship has only 1 turret.

A double turret is +2 to hit. A triple turret is +4 to hit. Damage is the same as a single turret. Comment -- this cuts down on the massive number of die rolls required for Book 2 combat. And it's the approach used in Mayday, so there's precedent in CT. It also accomodates weapon bays without requiring massive numbers of rolls.

I'd love to see the math for this, even after all those years. Is a double turret with +2 to hit and one damage roll if hit (or two if it's a pulse laser) statistically equivalent to two lasers? Or a triple turret with a +4 to hit? Also, how does that account for a missile turret launching 3 missiles at once (now it launches one missile)?

I'd also like to know the reference for this from Mayday, for research purposes.