Better Anti-Air Weapon for Gunship?

[Kilofix]

Assuming the standard Heavy Bolter, and 6 Hunter missiles (Heavy 1 - Str 8, AP3) for the second hardpoint;

What would be the ideal weapon for the first hardpoint of a Vulture Gunship from the following, in order to blow up an opposing flyer that may be AV10 or AV12?

• Twin - Multilaser (Heavy 3 - Str6, AP6)
• Twin - Autocannon (Heavy 2 - Str7, AP4)
• Twin - Lascannon (Heavy 1 - Str9, AP2)

Also, assume the opposing flyer will Jink.

 

Thanks for the opinions.

 

[Teetengee]

VS AV10:

Multilaser: 3*.75*.5*.5=.5625 HP per shooting phase (ignoring crash and burn chance from immobilized result as it makes the math dependent on enemy hullpoints remaining, as such, each hp is in fact all hp remaining 2/3*1/6*1/3=1/27 of the time)

Autocannon: 2*.75*2/3*.5=.5 HP per shooting phase (each hp is all hp remaining .75*1/6*1/3=1/24 of the time)

Lascannon: 1*.75*1*.5=.375 HP per shooting phase (each hp is all hp remaining 5/6*(1/6*1/3+1/6)=5/6*2/9=5/27 of the time or approximately 1/5.5 of the time)

Winner is Multilaser

 

VS AV 11:

Multilaser: 3*.75*.1/3*.5=.375 HP per shooting phase (EHIAHR 1/2*1/6*1/3=1/36 of the time)

Autocannon: 2*.75*.5*.5=.375 HP per shooting phase (EHIAHR 2/3*1/6*1/3=1/27 of the time)

Lascannon: 1*.75*5/6*.5=.3125 HP per shooting phase (EHIAHR 4/5*(1/6*1/3+1/6)=4/5*2/9=8/45 of the time or approximately 1/5.5 of the time [slightly less than before])

Winner is autocannon.

 

VS AV 12:

Multilaser: 3*.75*1/6*.5=.1875 HP per shooting phase (cannot penetrate)

Autocannon: 2*.75*1/3*.5=.25 HP per shooting phase (EHIAHR 1/2*1/6*1/3=1/36 of the time)

Lascannon: 1*.75*2/3*.5=.25 HP per shooting phase (EHIAHR 3/4*(1/6*1/3+1/6)=3/4*2/9=1/6 of the time)

Winner is lascannon.

 

Side Notes:

VS AV 10|11|12

One Missile will do average of .2083|.1667|.125 with an EHIAHR of 2/45(1/22.5)|1/24|1/27

One heavy bolter(3 shots) will do average of .25|.125|0 with an EHIAHR of 1/36|0|-

 

Keep in mind that this is true explicitly only when the number of hp is reasonable and it is the only weapon firing on the target. The more hp the target has, the more significant the random chance of instant death becomes and the better the lascannon and autocannon get. The more weapons you fire at the target, the greater chance of saturation of HP on the target and the lower your actual ave hp damage dealt per shooting phase. Since both of these hinge hugely on the hp remaining of the target, it is a little difficult to math them out.

(They are bs 3 correct? also to calculate a more accurate value multiply the average damage by (remaining hull points*EHIAHR+1-EHIAHR) but this will overestimate the damage from multishot weapons and from volleys of shots.) Double the HP damage if the opponent is not expected to jink and has no save otherwise.

[Kilofix]

@Tee - Cheers for your Mechanicum powered math engine!

[Teetengee]

No problem, I actually enjoy it, imperial weapons are fairly easy, especially if you ignore explodes results and hp saturation. I tried to do it once with de weapons (heat lance, haywire blaster, blaster) without ignoring those. It was not nearly so fun.

[Captain Idaho]

Why are you ignoring certain results on the damage table though? Lascannons have a 50% chance of getting a kill with a penetrate after jinks.

[thepowerofwar]

I feel that Explode results are a big consideration for me when shooting at vehicles( that's why I Melta).

[Teetengee]

A lascannon only has a 1/6+1/6*1/3 (~17.6% much less than 50%) chance of getting a kill on a penetrate which, while appreciable, is still relatively rare. More importantly, kill shots are only worth the enemy hull points remaining. Also I didn't exactly ignore it, the numbers are available in the parens for the chance of an explodes (on a flyer) given that you already caused a hp. Also then you need to factor in what other damage the vehicle already has (such as weapons remaining) which causes an even further headache. Remember that the new damage table has greatly reduced the chance of an explodes result.

 

Melta has a 1/3+1/3*1/6 chance of getting an explodes on a successful pen against a flyer, which is also far more likely due to the melta rule. Explodes occur much more often in that case.

[Kilofix]

After looking at Tee's numbers and some consideration - I think Lascannons are indeed the way to go. It will be hope for a lucky explosion or I probably won't waste time shooting at an opposing Flyer because it will otherwise probably take a few turns to down.

 

That being the case, I might switch from a Vulture to a Storm Eagle with 2 Twin-Las, plus a Multi-Melta for anti-air-air instead to deliver as much AP1 / AP2 as I can.

[Teetengee]

OK SO I have mathed harder, and now have the ability to take into account easily any one weapon type (any number of shots) against any armour type flyer or not, as long as the weapon is not ordnance, melta, or haywire.

I can also probably hack it out to multiple weapon types and ordnance, melta, haywire, but I a not as yet sure whether the math will hold out properly. Table is as follows

                                AV 10                          AV 11                          AV 12  
  HP Remaining        1           2          3         1         2       3          1          2        3
  Twin Lascannon   0.375   0.4444 0.5139 0.3125 0.3681 0.4236  0.25      0.2917 0.3333
  Twin Autocannon 0.4375  0.5156 0.5364 0.3398 0.3863 0.4001 0.2344  0.2561 0.263
  Twin Multi Laser   0.4636  0.5697 0.5962 0.3301 0.381   0.3932 0.176   0.1873 0.1875
  Heavy Bolter       0.2297  0.2553 0.2627 0.1199 0.1249 0.125   0           0          0
  Krak Missile x1     0.2083  0.2176 0.2269 0.1667 0.1736 0.1801 0.125    0.1296 0.1343
  Krak Missile x2     0.3733  0.4313 0.4498 0.3056 0.3449 0.3587 0.2344  0.2581 0.2673
 

Where the value in the grid is the ave HP dealt to a jinking flyer if that is the only weapon firing. This accounts for saturation and explosion. As you can see, for damage over time, the autocannon is the first or second best choice all of the time. The lascannon is the best choice at AV 11 3hp remaining or AV12  but is the worst of the three in all other cases. The Multilaser is the Best at AV10 and second best at AV 11 when there are only 2 or fewer hull points remaining. KEEP IN MIND THIS DOES NOT ACCOUNT FOR EXTRA HP DAMAGE DEALT BY HITTING A UNIT ONCE IT HAS NO MORE WEAPONS (As why bother at that point?).

[CoffeeGrunt]

Worth noting the chances of Weapon Destroyed and Immobilised. The former can nullify one-gun wonders like the Heldrake or Punisher Vulture.The latter now has a 1 in 3 chance of causing an automatic Crash and Burn.

 

More than one way to skin a cat...

[Teetengee]

I counted the immobilized results, but the weapon destroyed results cause issues when they start to compound and start dealing extra hps. The chance of neutralizing a given vehicle can be calculated, but I will have to do it on a case by case basis.

[Ishagu]

It's why Lascannons are the best option on Stormtalons.

 

You have the TL assault cannon to chip away fragile flyers, and the Las to penetrate tougher armour...

[Kilofix]

Give the above information, I'm changing my approach to:

 

Vulture with Twin-Multilaser and Hunter Missiles - for a Vector Dance rear shot against things with AV10 rear (Heldrake, etc.).

 

And Vendetta (with 3 Twin-Lascannon) or Storm Eagle (with 2 Twin-Lascannon, 1 Twin_Multimelta) - for a direct shot against things with AV12 all around (Storm Raven, etc.).

 

Thanks again Tee

[Teetengee]

No problem. Glad to help.