Call for Starship & Vehicle Combat Examples

[apoc527]

Perhaps I'm alone in this, but I find a lot of stuff in the combat section to be unclear and at times confusing.

I'd like to open this thread to examples of combat using the Vehicle and Starship rules in T20. ANYONE who's every done it could post and it would probably help someone out.

I'd be really appreciative if people with the experience could take a few moments and enlighten the rest of us. Thanks in advance!

 

[Flynn]

I posted something like this a month ago, so I'm very interested in seeing an example myself.

Thanks in advance,
Flynn

 

[cmdrx]

Here's just one small example using the Basic Ship Combat system.
Keep in mind that this is my interpretation. If something seems wrong please let me know.

For this scenario I am using the Corsair on p.333 vs. the Patrol Cruiser (refered to as PC) on p.336. Just to make things more simple I am giving the crews a flat skill base of 10.

Scenario begins with the Patrol Cruiser, with a sensor range greater than the Corsair (Mod/3 v. Mod/2), detecting the ship and hailing it. The Corsair is now aware of the existance of the PC, but does not respond. Encounter range is set at Short.

Round 1
Both sides roll for initiative. PC=3(+1) for 4 and the Corsair=14. The Corsair may act first this round, but a range check must be made. PC Astrogator rolls a 5(+10skill) for 15 while the Corsair gets a 19(+10)=29. The Corsair has the advantage and decreases range to Close. The Pilot initiates evasive manuevers as they close in on the PC, rolling 8(+10)=18. Looking on the chart that gives a +1 to the AC of the corsair (Now 11) for this round. Now the gunners fire.
Turret#1(B-Laser USP 1): 7+10(skill)+1(USP)=18.
Turret#2(B-Laser USP 1): totaL roll of 24.
Turret#3(B-Laser USP 1): 26.
Turret#4 (Missile USP 2): 21.
All turrets hit the PCs AC of 11. The PC has no armour so there is no reduction. 3d8(beam lasers) + 2d6(missiles) are rolled for a total of 22SI to the PC. In addition, each hit causes internal damage:
Hit#1: 70-Fire Control, 52-Battery. Randomly Determined by GM, Turret #1 is Hit (-1USP)
Hit#2: 52-Fire Ctrl, 56-Battery. Turret #2
Hit#3: 60-Fire Ctrl, 21-Battery. Turret #1 hit again, rendering it inoperative (USP=0)

Hit#4: Misc., 31-Cargo. 2.5dt lost.
Of course the PC could have used its lasers gainst the missile attack, but decided to save it for the counterattack.
It is now The PC's turn.
The Captain of the PC rolls to rally the crew into action. Roll is 10+10(Leadership) for 20 v. DC15. Successful. The Crew will enjoy a +3 (10/3 round down) to skill checks, saving throws, and attacks this round. The Pilot matches speed with the corsair, and the gunners open fire.
Turret #1 (Missile USP 0, Inoperative)
Turret #2 (Missile USP 1) 9(roll)+10(skill)+1(USP)+3(Capn)=23 vs AC11, hits.
Turret #3 (B-Laser USP 3) total 35 (Natural 19, but 20 is req for crit), hits.
Turret #4 (B-Laser USP 3) total 26, hits.
Damage is 1d6+3d8+3d8. The Corasir has no AR reduction, total of 28SI
The 3 hits are rolled as:
93-Electronics, 84-Computer. Computer is now acts as Mod/1
74-Engineering, 54-Jump Drive. Jump Drive down to J-1
90-Screens, Corsair has none so trickle down to Electronics, 87-Computer. Computer reduced to 0 and is now inoperative.

Corsair cannot initiate jump or have the computer run sensors or targeting and other special programs. But it can still manuever and fire.
Results of Round 1:
The Corsair has effectively reduced the PCs combat capabilty by nearly knocking out all of its missile turrets. But in return, the PC's more powerful triple beam laser turrets have inflicted a painful wound to the Corsair. With it's computer knocked out the Corasir will not be able to make a quick jump out, even then it's j-drive has been reduced to half of its normal capacity. The Corair has SI damage of 28 out of 145. The PC 22/145.


That's how I read it from the book, but I feel as if the initial astrogation roll (range check) should be affected by speed and maneuverability of the vessel (as per vehicle rules) The current rule on p.162 does not specify this, just a test of astrogation. I feel a faster ship is going to eventualy outrun a slower ship and widen the range considerably. Is this how it works or am I missreading it?

 

[apoc527]

Thanks Commander X! That's useful, and at least it lets me get at my questions easier. I actually posted the main question I had in another thread, but it can be brought up again with your example.

I see you interpreted "hit" as being a "single instance of a weapon doing damage through armor" instead of "amount of damage that a weapon does through armor." This makes it pretty hard to disable systems such as Power Plants, which often have ratings of 10 or more (though unlikely on small ships, even our Scout produces 4 EP). Also, at least as far as I can tell, it makes it better to have as many small weapons as possible instead of heavier hitting bays or spinal mounts, as that maximizes the amount of internal damage you can do. My thought was that since it's VERY unlikely for a ship's entire hull and structure to be actually vaporized (meaning the SI is reduced to 0), it made sense that instead a "hit" is damage penetrating armor. This would mean that ships are very likely to be disabled from a few lucky or well-placed (called shot) hits without taking all that much SI damage. I would say that all hits do equal amounts of SI as they do internal damage. Alternately, you *could* say that every point of damage "soaked up" by an Internal Damage hit does one less SI point to the hull. The other alternative is to use the Advanced Vehicle rules and say that the internal components have SI that gets taken away too.

I guess my problem with the hit defined as "one penetration of a weapon, regardless of damage rolled" is that it means that no matter how large a weapon, it can't destroy ANYTHING in a single hit. A meson gun, if it happens to hit the power plant, should completely smash it to pieces, not reduce it's output by 1 EP. What do you think? How did other versions of Traveller (CT specifically) handle internal damage? Was Scout vs Scout combat essentially down to "whoever gets hit first" or was it a more protracted engagement? Once you add in armor, the results are much less certain, and combat consequently becomes more interesting. Certainly, lower powered weapons will be less capable of penetrating some of the heavier armor. However, even that won't always matter, as you are fairly likely to penetrate with at least *one* point of damage. Because of these reasons, I think "hits" can only mean points of damage through armor. Yes, this makes space combat fairly risky business, but that's how I think it should be.

On a side note, I don't understand how you only do internal damage to vehicles on Critical Hits or non-confirmed Threats if using the Advanced Combat System. The shot doesn't just magically go through the vehicle missing everything, does it?

 

[cmdrx]

Glad it helped out apoc527.

Yes. Each time a battery does SI damage, you roll on the internal damage table. And yes one good lucky hit even with a Mining Laser could very well destroy a ship of really make its day a living heck. It is rare to roll 00 twice on the internal damage chart but it can happen.

This is very much like Classic and MT. You would sit for hours just whittling away each other's turrets and fuel tanks without realy causing serious damage. Combat with capital ships was a different matter.

Having alot of small weapons works well against ships that are unarmoured as in the example above, but remember that capital ships need those big guns to penetrate armour and even meson screens. Also the big guns have +40 modifyer to the internal location table. The big weapons also have larger critical ranges. Meson guns have a crit range of 15 with a multiple of x10. If it's a Spinal mount the range increases to 10! and then theres the radiation damage.... (owtch!)

So yes, a Meson Spinal gun is going to hut, badly. Lets look at an example:

My favorite is the ol' Type T on the Tigress Class (aka Happy Fun Ball). That would be the last one on the chart on T20s p.275. This sucker has a USP of 27, thats an automatic +27 to hit right there. Add to that the gun crew's skill, and if the computer has a sensor lock (Usualy +9 on capital ships) and this will hit pretty much anything out there. It does 16d20 + 16d12 radiation, and has a crit range of 10. Say it does hit, it's going to do serious internal damage because of the +40 to the roll. Meson guns will never do anything in the miscelanoues category, 10% chance it will hit the fuel tanks. but it will have a 44% chance of doing 'Special' damage. That's your serious owtch right there. (96-40 = nat 56 on d100)

I personaly gauge the type of internal damage by how much SI is done as well. A laser doing a hit for a battery, yeah frag a turret by 1 USP, but a Meson gun hit? Take out a Spinal or at least a bay.

I'm going to do another example with capital ships for you. It get quite interesting as you have more crew and more options. Sensor locks at range are truly evil.

 

[apoc527]

Ohhh! I forgot about the fact that the big guns get a modifier to the table. That would make a difference. Yup yup.

Still, it seems unfortunate that a single penetrating hit doing 1 point of SI damage is no more damaging than a penetrating hit doing 15 SI damage. I was reading my GURPS Traveller book to see how they work combat, and overall it's very similar, but for every 10% increment of hull damage, you roll once on their (much smaller) Internal Damage Table. I was thinking that maybe you could apply that to T20 and give a bonus roll on the Internal Damage table if the hit did more than 10% of the ship's SI in a single hit. I guess it wouldn't normally come into play, but it might make the really big hits that much more interesting.

I haven't played Traveller long enough, but it seems to me like the ships are relatively frail compared to the weapons they mount. It's not like Star Wars, where a Star Destroyer and Mon Cal cruiser can go multiple passes blazing away at each other with their turbolasers. This is totally cool with me, of course, but it is slightly different. Combat is much more "submarine" type than dogfightish.

I'm really looking forward to Power Projection actually. I'm hoping that will present a workable system for fleet engagements, that you might not want to run with T20's normal system.

THanks for the example, and I'll be eagerly awaiting the capital ship one!

 

[cmdrx]

Yeah, the 1SI internal being about the same as 15SI (or more) with respect to internal hits bugs me a bit as well. I think there should be something like if the hit is hard enough apply a mod to the chart, like there is for Spinals already. I think I'll come up with a house rule for it.

Classicaly, ships in Traveller have been frail in my experience, most do not bother to use armour, relying on sandcasters and screens mostly. When I do my personal designs from the demented minds from X-TEK, I squeeze as much armour as I can into it, not always possible mind you. But a ship with factor 15 armour is a sight to behold. My web site has numerous examples, all open game content btw.

If you can find it, check out Suppliment 9:Fighting Ships for examples of ships from classic Traveller. Currently available in the 'Big Floppy Book' format (reprints). I will be using the Gionetti class Light Cruiser for the capital ship example. Quick glance of it: 30Kdt with J5 M5, a Mod/9fib computer (and possibly system range sensors and comms) Armed with a Type J Meson Spinal (USP18 in T20), 200 Tri-Missiles, 50 Tri-Beams, 6 Twin Fusion, 24 Tri-Sandcasters, a 100dt Repulsor bay and a Type 9 Nuke Damper. But I guess there was no room for a meson screen or armour. This should be fun.

You are right in your assumption on Traveller ship combat, more like submarine than WWII Arial/Naval combat, which is what Star Wars displayed.

Next in line, Gionetti vs. Gionetti

 

[tenntrav]

How do sandcasters work and how do they stack up against armor or agility? Is the USP of one sand battery a straight increase to AC per laser shot, or does it effect AR as well?

If it only effects AC, then spending tonnage on armor seems the best purchase in this combat simulation.

 

[snrdg082102]

Originally posted by tenntrav:
How do sandcasters work and how do they stack up against armor or agility? Is the USP of one sand battery a straight increase to AC per laser shot, or does it effect AR as well?

If it only effects AC, then spending tonnage on armor seems the best purchase in this combat simulation.

Interesting question you have asked and one I'll attempt to answer, or hopefully give enough information so you can make an informed decision. Also, I need to clarify my idea of armor, which is anything added to the hull plating. AC0 is just hull plating, AC1+ is additional layers of specially constructed hull plating.

First, a sandcaster is a launcher primarily designed as a defensive weapon against lasers (CT) or beam weapons (TNE). Depending on the version of Traveller (CT, MT, TNE, T4, GURPS) the sandcaster has varying effects against attacks from PA, Fusion, and Plasma weapons as well.

Next, the sand is composed of ablative material in crystalline form that is poured into a 50 kg/110lb canister. When launched the canister comes apart, which allows the crystals to disperse forming a cloud between the defender and the attacker. When the attacker fires a laser, the crystals absorbs or relects/defelcts a lot of the beams energy away from the defender's hull. As the sand blocks the energy the crystals are used up, requiring further rounds to be discharged to keep up the protection.

The above is pretty much the same in all the Traveller variants. A difference exists between CT and TNE on how the cloud operates.

In CT the cloud drifts along the course and speed at which the sandcaster operator launched the sand. Which means that the defender will quickly maneuver out from behind the cloud while trying to return fire at and evade further fire from the attacker.

TNE on the other hand allows the location and shape of the cloud to be manipulated first by electromagnet fields, a combination of gravtic/magnetic fields, and finally by gravitics alone.

Finally, from my viewpoint sandcasters are best used in conjunction with agility and armor when the ship is equipped with the stuff.

Hope the above helps.

 

[manley_t]

2 things in your example

missiles do a base damage of 5d6 +1d6 per USP

Also, my interpretation was that all like weapons were joined together for the USP. So those 3 triple beam turrents would be added together in one attack for a single USP.

So Turret #1, #2 and #2 = 9 lasers (don't have the book, can't see what the USP is on this).

comments?

 

[cmdrx]

I was using the stats as they are in the ship write ups. The Patrol Cruiser on p.336
Missile racks says damage is 2d6. On p. 270 - Weapon Types the asterisk is only on the Nuclear Missiles, even though the caption says 'All Missiles' I assumed the base 5d6 is for nukes only.
Mind you, I always thought USPd6 for standard missiles was a bit whimpy. The PTB (Powers That Be) need to clarify this.

With regards to the turrets, yes you could clump them all into a single battery as most of the big ships do. Smaller ships tend to do one turret = one battery. You get more chances to hit that way. BTW a battery of 9 Beam lasers is USP4 and you end up wasting 3 lasers anyway as you need a total of 10 to get USP5. Better just to clump the two tri turrets into a battery for the USP4 and keep the other one separate for a USP3 shot.

 

[apoc527]

If I was making my own ATU, I'd set base missile damage to d8's, make the nukes a d10 with base 5d10, and make antimatter warheads (not canon) d12s with a base of 5d12. That seems about "right" to me.

 

[cmdrx]

The R&D boys at X-TEK have been playing around with variant missile warheads for ship missiles. My favorite is the possibility of AP warheads. I am using the rules for AP ammo to figure cost. A standard missile cost 5000cr. At TL15 a max AP missile (AP7) would cost 70x as much or 350,000cr. Quite expensive indeed, but can ignore AR7.

Add the possibility of AP Nukes. Missile penetrates armour and then detonates inside the target. Eeek!

And in GT we had things called Heavy Missiles...

Fun fun fun!

 

[apoc527]

I like the "antimatter shaped charges" (or were they nukes?) from the Starfire series by David Weber and Steve White. Actually, the antimatter warheads were just plain cool anyway. I like antimatter.

 

[Ellros]

I was using the stats as they are in the ship write ups. The Patrol Cruiser on p.336
Missile racks says damage is 2d6.

They figure that from a single rack in the turret, plus the +1 TL mod for being TL 13 or higher, equals a USP factor of 2, thus 2d6 damage for a HE missile.

There are inconsistencies though, since it "says" triple rack (which would be a USP of 2 to start), then add in the +1. Surprisingly, all the laser turrets in the ship examples are correct for base damage, but none add in the modifiers for higher TL.

 

[cmdrx]

The Patrol Cruiser is built at TL12 so the tri-missile racks are USP2

BTW I've followed the 'weapon damage' thread in The Fleet section and the general consensus is HE missiles do 1d6 per USP.

Now to get back on topic...
Next post is an example of Capital ship combat.

 

[cmdrx]

Combat example #2
using Gionetti class Light Cruisers

I am using the Gionetti from the Classic Suppliment #9, Fighting Ships.
Thats one of the cool things about T20, you can use Classic ships and they'll work fine.

The Gionetti class is a 30,000dt ship (Huge, -2AC) with the following:
J5, M5, Agility 5, Initiative +5
Model/9fib computer
Type J Meson Spinal (T20 USP 18)
20 USP7 Missile Batteries
5 USP9 Beam Laser Batteries
3 USP6 Fusion Gun Batteries
8 USP6 Sandcaster Batteries
1 100dt Repuslor Bay USP9
Nuclear Damper USP9
AR0, AC13 (AC15 vs Meson)
550 SI

The crew has a flat skill base of 10. And as is the case with most capital ships, there is enough crew to do just about all possible tasks in a single round.

Both ships become aware of each other almost instantly thanks to the very powerful factor 9 sensors. Encounter is set at extreme range.

Round#1
A range check is made. #1 rolls 13+10(skill)=23, #2 rolls 18+10=28. Gionetti #2 closes range to Very Long.
Initiative is rolled. #1 gets a 13, #2 a 21. #2 Acts first.
Captain rolls his leadership check, 24 v DC15. Crew gets +3 mod.
The Helm initiates evasive manuevers. roll 15+10(skill)+3(cap'n)=28. +2 to AC, now 15 this round.
The Sensor op rolls for jamming, 13+10(skill)+3(cap'n)+9(mod #) for a total of 35.
The other op rolls for sensor target lock, 8+10(skill)+3(cap'n)+9(mod#)=30 v DC15. Gunners now have a +9 (comp. mod#) +3 from the captain for +12 to hit(!)
And now for the Meson Spinal...
The range between vessels in Very Long, the range of the spinal is Medium. It will be at -4 to hit due to range.
The Meson Gun crew has an average skill of 10, add the spinals USP of 18, the captain's successful leadership +3 and the sensor target lock +9, -4 for range and the bonus to hit is an obscene +36. Equaly obscene is the fact that a Meson spinal has a critical range of 10-20. The roll is made, Gionetti #1 player winces, the breathes a sigh of relief as a 7 is rolled. No critical threat but against an AC of 15 the beam will hit with a total roll of 43.
Damage is rolled 16d20 with no meson screen reduction means all 191SI damage is applied. Meson guns also do Radiation damage, thankfully the Gionetti does have a Factor 9 Nuke damper so 16d12 is reduced to 7d12, for an aditional 41SI.
Now comes the hit location. Meson guns do both standard AND radiation damage table internal hits (2 for the price of 1). Also they are +40 on d100. Here it comes...
Regular Table: 21+40=61 Fire control, 70 = Battery. GM rules that #1 looses an entire battery (not just -1USP) due to the nature of the weapon. #1 has lost a missile battery, with 19 to spare.
Note: This is how things were handled in High Guard for big ships. Each battery hit removed an entire battery, until only one remained. Then it was -1USP
Now we roll for the radiation effect. 70+40=110 Special. Player #1 groans in agony. The specific special is rolled for 88. Gionetti #1 has his entire M-Drive fragged and fused into a molten blob of useless slag. Player #1 sobs as his ship cannot move and more painfuly cannot return meson fire as the ship can't move to aim the spinal! A total of 232/550 SI as well.

It is now Player #1's turn to act.
Stay to fight, or Jump out. Player #1 decided the 'damn the torpedoes' approach and attacks with everything he's got left, hoping next round he can get initiative and jump out.
Captian's Leadership roll: 22 successful, crew gets +3 bonus.
Pilots cant do much of anything right now.
Sensor ops try a sensor lock, but #2 is jamming, they need to get better than a 35 to lock.
Roll is 12+10(skill)+3(cap'n)+9(mod#) for a 34, oh so close, but no lock and no +9 to hit.

The remaining 19 Missile batteries let fly. Range to target is very long while missiles have a range of long (-2 hit), 10(skill)+9(usp)+3(capn)-2(range) give +20 to hit. Gunners roll.
To make a long story short I'll not post all the rolls for the 19 batteries.
All but 1 hit (crit failure) and 2 critical. Gionetti#2 did fire it's sandcasters which gave an AC of +6 vs 8 Missile attacks. (AC21) unfortuneately they were all innefective. 18 Batteries will hit, but the #2 Gionetti still has Point Defence weapons. The Repulsor bay does away with one battery. Roll of 10+10(skill)+9(usp)+3(capn)=32 vs. DC10+9(usp)+9(firers computer)=28. 5 beam Lasers try PD fire. 10(skill)+9(usp)+3(capn)=d20+22 vs. DC of 16+9+9=34.
4 of the salvos are destroyed. Leaving 13. Although its not in T20, Fusion guns were used as PD weapons back in HG and the GM allows this. Roll is same as per Laser PD. d20+19 to hit DC34 and only 2 missile salvos are blown to slag. 11 USP 9 missile salvos will hit.
11 9d6 hits cause a total of 300SI damage (owtch!), yes that included the 2 criticals.
Most of those 11 missile hits will take out weapons batteries and damage the fuel tanks.
3 of those hits did some serious damage.
Total internal Hits:
5 Missile Batteries gone
2 Laser Batteries gone
10% Fuel lost.
Jump Drive damaged, now down to J4
Manuver Drive damaged, now M4
The Repulsor bay took a hit, reducing USP to 8

And #1 ain't done yet folks!
The beam lasers fire. They have a total bonus of 22 to hit. Being short range weapons they will suffer a -6 to hit, reducing cumulative to hit bonus to +16. All 5 hit AC15, but no crits. they do a total of 5 9d8 hits for 180SI.
The internals are: 2 Laser Batteries out, 1 Missile Battery out, 20% fuel loss.

Just for giggles, Gionetti#1 fires the fusion guns at #2, regardelss of the short range fusion gun have. The GM has a house rule where Fusion guns have -4 instead of -2 per range band. The fusion guns will be at -16(!) to hit. With all the skills and bonuses this makes them +3 to hit the Gionetti #2 at this range. The threat range with these is 16. The natural rolls are 16, 7, 12 (19, 10, 15). One shot will miss, One shot threatens and the other just hits. The crit threat is rolled for 13+3=16 will hit AC15. Damage is 9d20+5x(9d20) or 46d20(!) for 475SI. total of 955SI out of 550. That one lucky fusion gun shot pretty much ended it for the Gionetti #2. Although the ship is not destroyed (remember 2x SI damage needed to totaly destroy a ship), it is a wrecked hulk. Player #2 is stunned. Game is over.

Results:
Gionetti #1, while having it legs broken by the Meson gun hit from #2 can still jump out.
Gionetti #2 is a wrecked hulk. Surviving engineering crew will prolly try to bring the J-Drive back online to emergency jump out (possibly missjumping in the process), provided #1 doesn't get initiative and perform a coup de gras on #2...

Lesons:
1. Spinals can hit just about anything, even at extreme range because of their high USP bonuses.
2. A sensor lock is your friend, especialy if the computer is advanced enough.
3. A high level computer is your friend, especialy when throwing missiles at someone. (+Mod# to DC)
4. Loosing the initiative can hurt, as your ship will not have performed certain functions such as evasive manuevers, and sensor jamming.
5. Critical hits can and will destroy you, especialy from fusion, particle and Meson fire. Had #2 rolled a critical on #1, the game would have been over. 16d20 x10 averages to 1600SI, more than enough to vape the Gionetti.
6. Do not taunt Happy Fun Ball, or any capital ship for that matter...

 

[apoc527]

Heh. That's pretty cool.

Ok, so just so I'm clear, Traveller never assumed that the amount of "SI" damage that was done to a ship actually corresponded to how much internal damage it takes. That's fine. I'm discovered most games work it that way now anyway, and I suppose it makes sense.

Just means that fight in my game wouldn't have been over. I still like the idea of giving a bonus on the internal damage rolls if you do over 5% or 10% of the ship's SI in a single hit. That would make it more likely to take out the powerplant in a single hit by rolling on the Special table more often.

I think I'd have to just say that fusion guns can't shoot that long a distance. I think there's even a rule in T20 that states they lose damage with range. Either way, that was just obscene, as you put it.

Meson Spinal Mounts are definitely your friend.

One thing though, that I would probably allow. Once the ships actually detected one another, I'd allow BOTH ships to start Sensor Jamming immediately. It's only fair, if you think about. Losing initiative shouldn't make you lose your ability to jam the sensors.

I guess that's why other games use discrete phases.

 

[manley_t]

These are *great* examples.

And, yes, my players tend to *anything* a big ship tells them to

as for the missile damage I was reading 'all missiles' while everyone else was seeing the radiation comment in the footnote. Without my book here at work with me, I'll defer to the majority on it. Though it's confusing enough at any rate (IMO).

 

[loconius]

just some food for thought, for a more devastating effect on internal damage... have a weapon do it's USP in hits to the internal damage table... just an idea, your examples sprung the idea, haven't used it yet.