I see comments aobut Mathammer all the time on the RT forum, but google has failed me. So what IS mathammer, and where can I find this?

http://community.fantasyflightgames.com/index.php?/topic/47672-mathhammer-making-ship-armour-count/

The tl;dr version is this:

Macrocannons are stupidly powerful in the hands of players, and make lances redundant. You fix this by making two major changes.

• Either reduce all armour by 12 to a minimum of zero, or increase all macrocannon, torpedo, and bomber damage by 12.
• Do not allow hits from any of these sources to stack. Each hit is resolved against armour individually.

More generally Mathhammer is a term from the tabletop, where players sit down and mathematically determine the likelihood of one army list beating each other by just assuming they do nothing but attack each other in fairly wide-open conditions. Given how intense the miniatures game is, these calculations get surprisingly elaborate, and then completely fall apart in an actual battle because how can my Dreadnought get killed by freaking Fire Warriors in melee combat?

With regards to the RPG though, Errant's link is what we're referring to. I cannot give enough support for this change to Macrocannons. I use the add 12 to everything/each hit individually rule and it has vastly improved Starship combat.

Although I'd point out that the one simple change isn't enough to fix all the problems with the starship combat system. If your players are good they will see through at least one other problem and it will become an exploit in the game. That's not a dig against smart players, either. I respect intelligent play.

Exactly, there's a difference between intelligent play and exploitation of rule issues. The Starship Weapons fix, commonly known here as "mathhammer" for reasons I don't really understand, helps deal with one of the latter that made starship combat ineffective at higher/more competent levels. It's also terribly non-reflective of the fluff, stories or other listed background. To demonstrate the theory behind the effect:

Standard Rules;

Macrocannon (1d10+3 damage) against armor 20.

1 Hit: No damage

2 Hits: Damage if Lucky

4 Hits: Average of 14 damage

6 Hits: Average of 31 damage

Adjusted Rules:

Macrocannon (1d10+3 damage) against Armor (20-12=8)

1 Hit: Approx. Ave. of 2 damage

2 Hits: Approx. Ave. of 4 damage

4 Hits: Approx. Ave. of 8 damage

6 Hits: Approx. Ave. of 12 damage

So, as you can see from above, the adjusted rules (via reduction of armor or increase of damage, they're equivalent) results in a more even distribution of damage. It also makes differences in armor more important, as each point of armor is applied to each hit. Ignoring armor therefore also becomes more important, increasing the effective value of Lances.

Although most of the Mathhammer focus is on mitigating the overwhelming side of combat, it also aids tiny combats. Two transports with a single thunderstrike and a crew of 30 are literally unable to injure each other (because they cannot get the DoS required to hit 3 times, at which point they'd still have to roll above average on damage.)

It's called Mathhammer because that's what the tabletop players call it. And that answers all your questions forever.

Also your two Thunderstrikes could injure each other with Crew Rating 30, firing at Close Range for +10 and then use the NPC Action of Target Lock for another +10 to raise their BS to 50, which gives them the 3 DoS needed every 5 shots on each other.

In my campaign for Mathhammer, in order to balance out salvoing your shots together now no longer doing anything, for every weapon you add to your salvo you get +10 to your Weapon Skill test, which mostly enhances NPC vessels.

Ah, you are correct, I missed that combination Erathia. Taken together then, there is a ~1% chance a transport with a thunderstrike cannon can injure another transport with a thunderstrike cannon. So after 12 hours of brutal close range combat, one of the transports will probably have inflicted 1 point of damage on the other.

As I recall, the initial reason for RT mathhammer was that salvo rules made lances pointless. That it also made NPC vessels viable was a welcome side effect.

As I recall, the initial reason for RT mathhammer was that slavo rules made lances pointless. That it also made NPC vessels viable was a welcome side effect.

Lances are not inherently "useless" - they're just not as good as macrocannons in all situations. I still think a lance/macro combo is the way to go for Raiders/Frigates. At Light Cruiser and up, pretty much go pure gunboats.

Other common changes include giving macrocannon broadsides (not batteries) storm and giving lances tearing or something, but the core add damage/individual hits rule is almost mandatory for npc vs pc balance.

I'm trying to come up with a different set of combat fixes. Having listened to different people give their house rules and having played a couple BFG-style combats with a buddy using some of these fixes, this is what I've come up with...and keep in mind that we're trying to bring back the BFG flavor. No more armor fixes, just firing fixes.

Starship Combat

1. Macrocannon damage only stacks per weapon component; multiple components can no longer salvo together.
2. Lances have no range modifications and each strength point fires separately. DoS count only for crits and each strength point can crit.
3. Broadsides' Strength are halved and fire twice.
4. Shields go down for the entire round.
5. The Abstract Method is used to keep track of small craft losses. Attack craft used in battle always make a maintenance check after that battle, in addition to any checks made during battle. Small craft form Wings made up of squadrons. A Wing can have as many squadrons as Flight Crew Rating/10 (rounded down). Bomber squadrons can only stack damage together from the same Wing. The damage of bombers is 1d10 + Flight Crew Rating/10 (rounded down).
6. Ships firing or being fired at are at -10 for augur checks.

#1 fixes the Macrocannon dominance, or is supposed to. No more than 4 STR can ever stack together this way.

#2 changes Lances to almost exactly what they are in BFG.

#3 makes NPC CL's and CA's more dangerous to PC escorts without going all Storm on them. We just didn't like all those even numbers of hits. We wanted some odd numbers.

#4 is because we never liked shields coming back as every ship fired.

#5 fixes small craft by splitting attack squadrons and creating some ferocious attrition, all without having to keep track of all those blast markers...and that was our most difficult fix...we just didn't want to let go of the detailed method. It ties small craft to your PF. Wealthier dynasties have more spare parts laying about.

#6 is another blast marker fix.