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Old 01-24-2017, 07:55 PM   #31
DirtyFret
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Sorry it took ages I have had an extremely busy real life schedule.

Links updated. Mods working in 1.5.5 OB (steam).

Let me know if issues persists, I'll try to be more quick with fixing them this time
Notes: The GAU data has been updated with the info from OrbitalATK datasheet
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Old 02-27-2017, 06:06 PM   #32
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Originally Posted by DirtyFret View Post
Sorry it took ages I have had an extremely busy real life schedule.

Links updated. Mods working in 1.5.5 OB (steam).

Let me know if issues persists, I'll try to be more quick with fixing them this time
Notes: The GAU data has been updated with the info from OrbitalATK datasheet
Hi Dirty Feet,

kudos for your efforts ! Just curious, which entry for the GAU-8 means what in the lua file. Example HEI:

Da0 = 0.0009,
Da1 = 0.0,
mass = 0.378,
round_mass = 0.681,
cartridge_mass = 0.360.

I'm just wondering if the names and mass data figures in the .lua are OK and aligned with this simple fact sheet about the ammunition:

https://www.orbitalatk.com/defense-s...Fact_Sheet.pdf

This data sheet says cartridge weight/mass is 0,681 kg, projectile/round mass is 0,378 kg. For both, naming and mass data in the lua seems different/mixed up (wrong?). If it's only namig error, but the program (despite wrong naming, still consequently) handles the values right when running, it's fine. Was just surprised, whether the values and names and datas might got mixed up somewhere along the way, and if this could be the reason for decreased efficiency lately? Would be nice to know how this names and datas are used in program.

There is also typyical dispersion on that pdf in (I guess!) milrad (mr), dunno what pyisical unit the Da0 value means in the .lua? If it is indeed milrad on the sheet, then actually "mr x mr" makes no sense in my opinion, as milrad is normally a unit for angle (of the dispersion cone), alternative measurement for a more widely used "MOA" for rifle scope adjustment.

Maybe you can reflect on these?

Last edited by Razor18; 02-28-2017 at 06:32 AM.
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Old 03-01-2017, 07:22 PM   #33
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Originally Posted by Razor18 View Post
Hi Dirty Feet,

kudos for your efforts ! Just curious, which entry for the GAU-8 means what in the lua file. Example HEI:

Da0 = 0.0009,
Da1 = 0.0,
mass = 0.378,
round_mass = 0.681,
cartridge_mass = 0.360.

I'm just wondering if the names and mass data figures in the .lua are OK and aligned with this simple fact sheet about the ammunition:

https://www.orbitalatk.com/defense-s...Fact_Sheet.pdf

This data sheet says cartridge weight/mass is 0,681 kg, projectile/round mass is 0,378 kg. For both, naming and mass data in the lua seems different/mixed up (wrong?). If it's only namig error, but the program (despite wrong naming, still consequently) handles the values right when running, it's fine. Was just surprised, whether the values and names and datas might got mixed up somewhere along the way, and if this could be the reason for decreased efficiency lately? Would be nice to know how this names and datas are used in program.

There is also typyical dispersion on that pdf in (I guess!) milrad (mr), dunno what pyisical unit the Da0 value means in the .lua? If it is indeed milrad on the sheet, then actually "mr x mr" makes no sense in my opinion, as milrad is normally a unit for angle (of the dispersion cone), alternative measurement for a more widely used "MOA" for rifle scope adjustment.

Maybe you can reflect on these?
Hey Razor,

Those are very good questions but unfortunately I don't have answers for them , only guesses .

I noted the same discrepancy in naming convention and I just assumed and deduced that since the original .lua file has on the GAU_AP ammo "cartridge_mass=0.083" that this value cannot be the real physical weight of the whole cartridge. The lines "mass" and "round_mass" I assumed to respectively be "projectile mass " and "cartridge mass" because the values closely represented real life values.

I have tried to figure out the method with which DCS computes AP damage but I do believe that "v0" and "mass" values play a part on those calculations in conjunction with "AP_cap_caliber". I haven't figured what that "cartridge_mass" value stands for or what its use is. The "cartridge_mass=0.360" is from the original .lua and I haven't altered it at all. It could have some role in explosive damage calculations because that value matches the "explosive" (mass) value.

The Da0 is a somewhat mystery to me. Even though, I (and many others) know by testing that by decreasing it you reduce the spread and by enlarging it the spread increases. I don't believe it to be of any real physical value(e.g. milrads). I believe it could be just a coefficient in the bullet spread/spawn calculations inside DCS game engine. I must admit though that I am a total amateur in this matter and that "MOA" measurement you refer to is unknown to me .

Hope my guesses answered some of your questions Razor, if you do happen to stumble on some info or revelation by testing or otherwise please do share

Regards

D-F
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Old 03-01-2017, 09:35 PM   #34
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I must admit though that I am a total amateur in this matter and that "MOA" measurement you refer to is unknown to me .
It's just another angular unit, Minute of Angle. As a minute is for an hour, it is 1/60th of a degree.
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Old 05-13-2018, 10:41 PM   #35
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Sorry for dragging this thread up from the dead, but has anyone gotten this to work with 2.5.x?
As a small report I get a hard CTD when I try to load this mod, after the loading logo and just before the main menu GUI should appear.

Related errors from dcs.log is:
2018-05-13 21:39:12.625 ERROR EDOBJECTS: Destruction shape not found AVIASHTAB_CRASH
2018-05-13 21:39:13.129 ERROR WEAPONSBASE: weapons_table.weapons.shells_aiming.M68_105_HE.precalculateAimingTable is not a boolean
2018-05-13 21:39:13.129 ALERT wInfo: Descriptor not found weapons.shells.M2_12_7_T
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Old 05-14-2018, 02:03 AM   #36
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Originally Posted by TheBamse View Post
Sorry for dragging this thread up from the dead, but has anyone gotten this to work with 2.5.x?
As a small report I get a hard CTD when I try to load this mod, after the loading logo and just before the main menu GUI should appear.

Related errors from dcs.log is:
2018-05-13 21:39:12.625 ERROR EDOBJECTS: Destruction shape not found AVIASHTAB_CRASH
2018-05-13 21:39:13.129 ERROR WEAPONSBASE: weapons_table.weapons.shells_aiming.M68_105_HE.precalculateAimingTable is not a boolean
2018-05-13 21:39:13.129 ALERT wInfo: Descriptor not found weapons.shells.M2_12_7_T
https://www.dropbox.com/s/teqcyb3ab3..._tweak.7z?dl=0
That is the link to the mod for the GAU-8 i have updated it, go ahead and give it a try!
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Old 05-14-2018, 01:40 PM   #37
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Thank you so much!
Haven't tried the effects but installed it via remote control on my home-pc (at work at the time of writing this) and game starts just fine.

Again, thanks! <3
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Old 05-14-2018, 04:46 PM   #38
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Originally Posted by DirtyFret View Post

The Da0 is a somewhat mystery to me. Even though, I (and many others) know by testing that by decreasing it you reduce the spread and by enlarging it the spread increases. I don't believe it to be of any real physical value(e.g. milrads).
In doing some testing in active pause using the F-5e, since it has a gunsight with a known diameter in mils, the Da0 does correspond very well to mils. 0.0040 is 40 mils.

Testing seems to show that this is the absolute largest diameter within which all shots must land and that there's a randomizer that is causing a certain percentage of shots to land within an area, say, 50% that size.

Right now I'd hazard a guess that for a Da0 of 0.0008, 50% of rounds will impact within an area 4 mil in diameter while the remaining 50% are spread anywhere from 4.1 mil to 8 mil, with very few rounds actually spreading out the full 8 mil.

Interestingly, there's a video around showing an M61 Vulcan cannon, mounted on an aircraft, being tested on the ground. The group it shoots is significantly smaller than 8 mil, indicating that 8 mil is probably a failure standard and not typical expected performance.

A Da0 of 0.0005 for the GAU-8 seems appropriate, especially considering accuracy values used for comparable cannons in the sim.

Last edited by Aries144; 05-14-2018 at 04:48 PM.
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Old 05-16-2018, 03:22 AM   #39
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Originally Posted by Aries144 View Post
In doing some testing in active pause using the F-5e, since it has a gunsight with a known diameter in mils, the Da0 does correspond very well to mils. 0.0040 is 40 mils.

Testing seems to show that this is the absolute largest diameter within which all shots must land and that there's a randomizer that is causing a certain percentage of shots to land within an area, say, 50% that size.

Right now I'd hazard a guess that for a Da0 of 0.0008, 50% of rounds will impact within an area 4 mil in diameter while the remaining 50% are spread anywhere from 4.1 mil to 8 mil, with very few rounds actually spreading out the full 8 mil.

Interestingly, there's a video around showing an M61 Vulcan cannon, mounted on an aircraft, being tested on the ground. The group it shoots is significantly smaller than 8 mil, indicating that 8 mil is probably a failure standard and not typical expected performance.

A Da0 of 0.0005 for the GAU-8 seems appropriate, especially considering accuracy values used for comparable cannons in the sim.

C'mon ED, when are you going to fix these? It's been half a decade at least at this point since the GAU-8 one was reported!
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Old 05-16-2018, 06:31 AM   #40
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I am curious what happens if CEP-50% and CEP-80% concepts were confused.

Turns out it's an error of magnitude 0.65 when distribution is Gaussian and 0.50 if distribution is triangular. This is consistent with your 17 to 9 correction.

In short, if someone works out an error amount assuming they are complying with a CEP 50% specification and someone comes along later and says, "Oh, sorry, I mean 80% of bullets are in that ring, not 50%." You'd be off by roughly a factor of two.
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