Changes A-10/A-164 Cannon Values

[LorenLuke]

When merged this pull request will:
-Reduce A-10/A-164 Cannon dispersion to realistic levels
-Tweak current "Gatling_30mm_HE_Plane_CAS_01_F" damage values
-Add Armor Piercing ammo type for 30mm Gatling
-Add Combat Mix ammo types (4:1 and 5:1 AP:HEI) and magazines for 30 mm Gatling
-Allows full rate of fire at lower framerates than was otherwise possible

[commy2]

You need over 60 FPS to fire at this rate. This is impossible in multiplayer, the fire rate will vary depending on your FPS. This is not desirable.
Vanilla has 0.03, which is just about 34 FPS for constant fire rate.

[commy2]

This is a new classname created by ACE. Classnames are in global space, so it needs to be tagged.

[kymckay]

There's a history of PRs to make changes to the A-10 cannon, see #4497

Previously we ended up closing them after consulting someone knowledgeable as it wasn't clear that the changes were realistic (for some details the opposite seemed true). However, that's not to say this PR should suffer the same fate - I would just recommend providing some reference for these changes.

[commy2]

I see references for the dispersion change. I don't see references for the ammo mix (ratio) and the functions of these two ammo types.
Undoubtedly the m134 gau-17 gatling gun has a higher fire rate than what is, with consideration of the game's simulation frame rate, set by the base game.
Most of my concerns regarding this PR (and probably all of the old ones) are on the technical side.

[LorenLuke]

ammo mix ratio

https://en.wikipedia.org/wiki/GAU-8_Avenger#Design
The standard ammunition mixture for anti-armor use is a five-to-one mix of PGU-14/B Armor Piercing Incendiary, with a projectile weight of about 14.0 oz (395 grams or 6,096 grains) and PGU-13/B High Explosive Incendiary (HEI) rounds, with a projectile weight of about 13.3 oz (378 grams or 5,833 grains).[8] The PGU-14/B's projectile incorporates a lightweight aluminum body, cast around a smaller caliber depleted uranium penetrating core.

https://fas.org/man/dod-101/sys/ac/equip/gau-8.htm
A typical combat load for the GAU-8 would include 1,100 rounds of 30mm high explosive or armor piercing ammunition. The 30mm API is mixed with 30mm High Explosive Incendiary (HEI) at the factory and is called Combat Mix Ammunition. The ratio of API to HEI rounds in the Combat Mix is 4:1. Combat mix is a sequential mixture of DU and HEI rounds in which 1 HEI round followed by 4 DU rounds are fired by the AN/GAU-8 gatling gun. DU is the primary munition for the A/OA-10 in a combat environment.

[Drofseh]

I like the approach with the submunitions and support this being included.

Here are some things I would like to see.

• More verbose classnames, for these in particular ACE_1000Rnd_Gatling_30mm_Plane_CAS_CM, ACE_30mm_mix, and Cannon_30mm_HE_Plane_CAS_03_F (which should both be tagged with ACE_ as commy says, and also I think should be AP, not HE).
• A single rate of fire. The original selectable rate was only available very early on and was replaced with just one 3900 rpm setting.
• The sources I've seen for the combat mix either say 5:1 AP to HE or 4:1 AP to HE. I'm not sure which is correct and it's possible that it changed at some point, but I'd prefer 4:1 (which is currently what the code has).

[LorenLuke]

Progress commit-
Changed some values back to before (misread a classname, oops!)
Tweaked: Values for HEI rounds
Tweaked: Added more verbose class names for ammunition and magazines
Tweaked: Time between shots now 3x longer, but fires in 3rnd submunition bursts. Now supports full, uninterrupted maximum ROF at ~20FPS or higher.
Added: Dedicated AP round and magazine for 30mm cannon
Added: Combat Mix 4:1 ammo and magazine
Added: Combat Mix 5:1 ammo and magazine

[LorenLuke]

Review ready. Request player feedback of how it plays. Unsure if CM 4:1 should be loaded by default to A-10/A-164, or if the HEI should remain the default loaded magazine.

[Blutze]

If you are making a difference between HE and AP, you should make sure they have different penetration values. Currently you are just inheriting the vanilla ammo's caliber = 1.4, giving you ~20mm of RHA at ~900 m/s impact velocity. For both ammo types.

[LorenLuke]

Bumped caliber values for AP rounds to penetrate between 50 and 70mm of Rha based on figure given.

[Drofseh]

Unsure if CM 4:1 should be loaded by default to A-10/A-164, or if the HEI should remain the default loaded magazine.

I would have the CM loaded by default as it is much more versatile.

[LorenLuke]

Ready for final review.

[PabstMirror]

RPT now throws error

21:43:13 No class Cannon_30mm_HE_Plane_CAS_01_F
21:43:13 No ammo class Cannon_30mm_HE_Plane_CAS_01_F
21:43:13 No class Cannon_30mm_HE_Plane_CAS_01_F
21:43:13 No ammo class Cannon_30mm_HE_Plane_CAS_01_F

I think this should be
Gatling_30mm_HE_Plane_CAS_01_F
instead of
Cannon_30mm_HE_Plane_CAS_01_F