Broadsides

[Talon]

Reading TUV last night, I started thinking about the method of simulating broadsides (multiple attacks at the same OCV) quickly.

 

This morning, I did some playing around with spreadsheets and came up with something that does a decent job of simulating repetitive rolls:

 

To resolve X attacks made at the same OCV, make a single Autofire attack with X shots and an OCV bonus of X-1. Thus, 10 shots is Autofire 10 with +9 OCV; 50 shots is Autofire 50 and +49 OCV. The resulting odds are about as close to the actual odds as you're going to get while using 3d6.

 

(I'm dangerous when bored.)

[BobGreenwade]

So you're saying that this would have about the same odds as rolling each attack separately?

 

If so, I think this would be a good thing to stick in the FAQ -- and someone will have to remember it if there's ever a second edition of TUV.

[Talon]

Originally posted by BobGreenwade

So you're saying that this would have about the same odds as rolling each attack separately?

 

 

Yup. It's not perfect, of course, but it's more than close enough given its simplicity.

[TaxiMan]

Restating it so you can tell me if I get it:

 

With X equal attacks, add X-1 to the OCV and use Autofire rules to determine how many shots hit.

 

Cool again! Let's do a simple test. Say I need a 10 or lower to hit for a single shot (50%). If I had 100 cannons, odds are really good that 50 will hit (the standard deviation is small with 100 rolls). I'll almost never get 99 and almost never get 1 hit.

 

With the simplified rule I'd roll for Autofire against 10 + (100-1) = 109. If I roll 10 I hit about 50 times. If I roll 18 I hit 4 less, and if I roll 3 I hit about 4 more.

 

Not bad! I wondered if I'd find an obvious flaw and I didn't! Since keeping the game fast keeps it fun for my group, I'll remember that trick. Very useful!

[Talon]

You got it right.

 

Technically, adding (X-1) * 1.25 OCV gets you near-perfect results...but why bother, X-1 is close enough. It errs on the side of giving fewer hits, and since it's usually NPCs shooting at the PCs, fewer hits is probably good!

[Gary]

This idea breaks down on the extremes like most ideas. For example, if the average attack needs 14- to hit (91% chance), 100 attacks should result in roughly 91 hits. Instead, you'll get an OCV of 99+10 vs 7. An average roll of 10 would result in about 46 hits.

 

The same holds true in reverse. A 7- to hit is about 9% chance. 100 attacks should result in 9 hits on average. Instead, you get an OCV of 99+7 vs 10. An average roll of 10 would result in about 43 hits.

[pinecone]

Actually that makes it cooler for me I have an intuative feel that a buch o bumpkins who probibly could not hit the side of a barn can with volly fire hit far better as a group and a bunch of sharpshooters are better use as free firing marks men instead of in volly...so for at least some applications this is a very nice method...

[TaxiMan]

Originally posted by Gary

This idea breaks down on the extremes like most ideas. For example, if the average attack needs 14- to hit (91% chance), 100 attacks should result in roughly 91 hits. Instead, you'll get an OCV of 99+10 vs 7. An average roll of 10 would result in about 46 hits.

 

Awww, crud Gary! I was trying to find where it failed & did a lousy job - forgot to go for abnormal odds to hit. You did - kudos to you!

[Wyrm Ouroboros]

Hmmm. Knew I saw this somewhere.

 

In the 'Star Hero' book, they make recommendations for broadsides and the like. Paraphrasing, they recommend it being treated as one 'multiple-Power' attack as per P 234 in the 5th Ed. book. Considering it, it -might- be a good way to do it, but 'multiple Power attacks' tend to be an all-or-nothing sort of thing -- everything hits or nothing hits, which generally sucks when you're dealing with the Millenium Falcon vs. a Star Destroyer. I can think of two good ways of doing it, both of them needing to be adjucated fairly closely by the GM...

 

1) For Large Craft Vs. Small Craft: Modified Suppression Fire. In a broadside, each weapon emplacement is directed to fire into a specific area of space, generally exclusive, and the weapons might even be 'locked in' to fire ONLY into that particular cone of fire. If the ship passes through the area that's being 'suppressed', it automatically gets attacked as per suppression fire. Use an 'average crew skill' OCV, and remember the -2 Penalty, the -1 per hex/cluster into which they're firing, and the range penalties. In general, the ship won't get hit very frequently. To do a quick 'sum-up', roll once for ALL weapons, then presuming they hit, have them hit a maximum of once for every CV they hit by. (Yes, it's autofire, but it's 'light' autofire.) Use average damage protocols.

 

Example 1: The MF is flying past a SD. 50 turbolasers run by OCV 5 trained crewmembers are blasting an anti-small-craft pattern. During the Falcon's run, it will pass through the 'attack cones' of 30 turbolasers. Each turbolaser covers a 3-hex cluster, and will probably try to peg the Falcon on its way past. The Falcon is flying at a range to give the gunners a -3 to their OCV, but Leia is piloting and so the Falcon only has a DCV of 5. The gunners need the GM to roll an 11 + 5 - 5 = 11 - 2 - 3 = 6 or less to hit. Wonder of wonders, the GM rolls a 3; the Falcon takes 6 - 3 = 3 hits from the turbolasers.

 

This, obviously, is a good 'space opera' dramatic space battle sort of thing; on the other hand, the big ships should only need to hit once or twice to blow the little ships out of the sky/water/whatever. If you want to run a more lethal 'large vs. small ship' combat, or if your 'large ship' guns are less damaging to the small ships, have the small craft take one hit for every CV for every 'hex cluster' that the gunners are covering. In the above example, instead of taking only 3 hits from the 30 turbolasers, the Falcon would take 3 x 3 (each gunner 'suppressing' 3 zones) = 9 hits. If a 6 was rolled, they would take 3 hits; if a 7 was rolled, then they dodged well enough.

 

2) For Same-Sized Craft: Autofire, Modified. This should be nasty and bloody, because if the same-sized craft are pulling broadsides on each other (whether in space or on sea) they really, honestly, truly are going to tear each other to shreds. However, things happen as follows:

 

The ship's pilot should be able -- required -- to enable the gunners to fire a broadside. A skillful pilot may well be able to give OCV bonuses, or at least his own ship a DCV bonus , e.g. 'crossing the T' of the other ship, to broadside them without getting broadsided in return.

 

Using the 'Average Crew Skill' OCV, and paying attention to the range/size modifiers, salvo the guns. (Briefly, view everything as being on 'capital scale' -- one hex is the size of the ship, so how far away is that other ship??) If you hit right on, 50% of the weapons will strike. For every 1 CV higher/lower, you gain/lose either 5% or 10% of your broadside's striking power, depending on how bloody you want the combat to be.

 

Example 2: General Tigh heaves the Galactica around and gives a Cylon Base Star the benefit of her broadside. Pilot skills are effectively the same; no OCV/DCV bonuses. Galactica's gunners are well-skilled (and hate cylons, but that's another story), with a 7 OCV. Their 40-gun broadside, which are working Mega-Scale for range, are only at a -1 Range Penalty to hit the Base Star. The Base Star has a 4 DCV, so the Colonial gunners need only an 11 + 7 - 4 = 14 - 1 (range) = 13- to hit. The GM rolls a smashingly good 6; that's 13 - 6 = 7 higher than needed. 50% + ( 7 * 5 ) = 50% + 35% = 85% of the Galactica's guns will pummel the Base Star. With luck, that one is going to be out of the fight real soon.

 

A note on #2: considering the massive ranges and the like, these sorts of broadsides/attacks should be delayed somewhat before they reach their target -- a one-phase 'travel time' or what have you, if only to give the doomed ship time to get off a salvo of their own. In these sorts of combat, at least in space and not in a surprise situation, every ship should be permitted a minimum of one broadside, i.e. that 'phase 12 attack'.

[Talon]

Thanks for keeping me honest, Gary!

 

Turns out that the OCV bonus needs to be (X - 1) times double the attack's hit percentage. For 10-, this works out to X - 1. For other percentages:

 

[EDIT: Oops, copied the wrong column. Numbers changed.]

 

3-: +1 OCV per 100 shots

4-: +1 OCV per 25 shots

5-: +1 OCV per 10 shots

6-: +1 OCV per 5 shots

7-: +2 OCV per 3 shots

8-: +1 OCV per 2 shots

9-: +3 OCV per 4 shots

10-: +1 OCV per 1 shot

11-: +5 OCV per 4 shots

12-: +3 OCV per 2 shots

13-: +5 OCV per 3 shots

14-: +7 OCV per 4 shots

15- or better: +2 OCV per shot

 

(To make it easier, the "minus 1" doesn't really matter once you get huge numbers of shots, so you can drop it.) Some of those are approximations, so if you compare (using Gary's method) against a huge number you'll be slightly off, but IMO this is more than close enough for a game, and kicks serious butt over just using MPAs.

[Blue]

Wow! I read the entire thread and my brain didn't melt. I am a gaming geek!

 

Pretty interesting stuff. Not sure I'll need it in the short-term, but I'll print and file it away just in case.