[FIXED] M-61 Vulcan and Gau-8 Avenger dispersion values

[Raven (Elysian Angel)]

Yes that same Wiki article indeed stated that. But I just went to check the DCS Hornet manual and found this:

 

 

Source: X:\DCS World\Mods\aircraft\FA-18C\Doc\DCS FA-18C Early Access Guide EN.pdf on page 131.

[ams999]

Luckily, as far as dispersion is concerned it makes no difference.

[nighthawk2174]

So I got some time on my hands and did some investigation of that F4 hud tape. Since the aircraft is maneuvering quite hard it will be quite hard to get solid numbers but we can get approximate values.

 

At this moment the pilot lets off the stick and we get a relatively tight grouping as the planes nose stops moving much. The circles represents the approximate circle of dispersion for the shells at the range at which the tracer burns out in relation to the reticule.

 

 

The 21 has a wingspan of 23.5ft and in the screenshot below has a size of ~122px. Giving a scale of 5.177px per ft. Now the best estimate of the dispersion pattern is ~100x100 to 125x125 px. This gives a circle with a radius of about ~11-13ft at the range at which the shells tracer is no longer visible. This is backed up by the inner reticule being 25mills in size and considering the circles are about half the size it fits. Now in the video this is about 1 sec but I have no clue how far the shell would have gone in this 1 second.

 

So unless someone can give me a rough number for that I will have to hold out on giving a range number to the above values. But if we think about this the range at which the in game vulcan would have to be at inorder to achieve the above values would be around 650-750ft (assuming its Da0 * 8 * 1000 = mills) and 500-600 ft if it's Da0 = mills. Yet the approximate range to the mig (let alone the shells in the background) is just around 1200ish feet.

Edited September 14, 2019 by nighthawk2174

[NineLine]

[nighthawk2174]

And your point is? We're talking about the raw dispersion values here, which are independent of pilot error and random stick movements.

[NineLine]

Point is this has been discussed before, and nothing has shown a change is needed.

[ams999]

Point is this has been discussed before, and nothing has shown a change is needed.

 

Respectfully, I don't agree with that statement. Though it was discussed before there was a lot of conjecture as to 'well, it just gets more inaccurate when mounted in the airplane'.

 

Quoting myself here but this video demonstrates quite clearly that this is not really the case (and is even considered in the design specifications).

 

Concerning mounted on the ground or on a plane I don't really see a problem as showcased in this video of the GAU-12/U used in a gun pod on an AV-8A.

 

 

From the video:

 

- on a fixed mount on the ground: design specification 5 mil, achieved 3 mil

- on the airplane: design specification 7 mil, achieved 5 mil

 

This shows that

a) the ground and plane mounted accuracy doesn't deviate by much even when fired from a moving aircraft (and this is pod mounted, not mounted inside the fuselage with better center of gravity concerning recoil)

b) a gatling gun is very well capable of being *more* accurate than design specification

 

So I would expect the same (i.e. not a lot of difference) for the M-61, too.

[nighthawk2174]

Except it does need changed as ams999 said it has been discussed but everytime nothing came of it, and for such a simple fix too... The documents from earlier and various videos have shown the dispersion in game is exceptionally high.

[NineLine]

Except you ignored this reply here:

https://forums.eagle.ru/showpost.php?p=4029576&postcount=10

 

I think there is a disconnect in what the settings mean and what some of you thing the settings mean.

 

SO again, its been discussed and there hasnt been any proof that it really needs to be changed, the gun is very effective in DCS.

[nighthawk2174]

Right I guess I need better word my statement, over a long burst the area set by the value Da0 round will spread through them more or less evenly:

 

 

But how does that invalidate all the documents and videos presented here as evidence that the M61 dispersion should be around 5mills for a 80& circle. Just looking at the original images I posted the 80% circle is on average just around 5mills. With the rounds that do fall outside of this zone the majority are just outside of the main grouping with one or two being outliers well outside the main grouping. One question though where did you get the values for the guns? What made it so the values of 22 and 17 were set for the Vulcan and avenger respectively.

Edited September 18, 2019 by nighthawk2174

[Fri13]

Question is not are the weapons effective, but are the weapons accurate.

 

If dispersion in DCS is 10 mil and in reality it is 5 mil, that is a huge inaccuracy between reality and DCS. Even 7 mil vs 5 mil is too much.

 

I wouldn't want that gun is 1-2 mil either, but it's it too much to ask to get a official adjustment to be 5 mil in DCS if it is reality 5 mil?

 

Go by the specs, not by "it is already effective".

[nighthawk2174]

This ^ how come the GSH23 and 301 and the BMP's gun all have their approximate dispersion values (.0005,.0007,.0004) yet the M61 and gau-8 stated to have around 5mills for their 80% circle are .0022 and .0017 respectively? I'm not saying set it to 5mills exactly but something like 6-7 would be a far better representation of the guns performance than 22.

Edited September 18, 2019 by nighthawk2174

[NineLine]

Question is not are the weapons effective, but are the weapons accurate.

 

If dispersion in DCS is 10 mil and in reality it is 5 mil, that is a huge inaccuracy between reality and DCS. Even 7 mil vs 5 mil is too much.

 

I wouldn't want that gun is 1-2 mil either, but it's it too much to ask to get a official adjustment to be 5 mil in DCS if it is reality 5 mil?

 

Go by the specs, not by "it is already effective".

 

As stated in the previous thread, the team is happy with the settings we have now. I also know it has been pointed out that what you are seeing in the files you are looking it isn't necessarily what you think it is. Anyways I was just jumping in to remind you this has already been discussed, if you guys want to keep on beating this drum, that's fine, but it has been answered already.

[nighthawk2174]

Right but why are they happy with it? Where did the numbers come from for the current dispersion values? Additionally I will say it again:

the GSH23 and 301 and the BMP's gun all have their approximate dispersion values (.0005,.0007,.0004) yet the M61 and gau-8 stated to have around 5mills for their 80% circle are .0022 and .0017 respectively? I'm not saying set it to 5mills exactly but something like 6-7 would be a far better representation of the guns performance than 22.

[Habu23]

In addition to my comments on engine and turn performance on the A-10, it would be nice if this issue received dev attention. 80% of rounds should land within 5 mils, and 100% of rounds should land within 13 mils. This video does a great job showing how this improved/modded mil dispersion appears in DCS. If it is as simple as modifying a text file, it would be nice if the developers could make this a permanent fix for future patches.

 

 

 

 

 

Habu

[Habu23]

I've taken to the forums to discuss some issues I have seen with the A-10, and as a driver of the jet wanted to clarify the rated accuracy of the GAU-8. 80% of rounds should land within 5 mils, and 100% of rounds should land within 13 mils. This video does a great job showing how this improved/modded mil dispersion appears in DCS. If it is as simple as modifying a text file, it would be nice if the developers could make this a permanent fix for future patches.

 

 

 

 

 

Habu

[nighthawk2174]

-T = 1:45

 

now having found this lets compare this footage to DCS

 

Each result individually

 

 

- DCS

- Video

 

 

Overlayed:

 

 

 

 

*note circles moved to center of reticule to compare sizes. Red = DCS, Blue = Video, and yellow = mod

 

Now lets go into the code and set the value to .0006 and compare:

 

 

much better...

 

 

[NineLine]

Hey NH, thanks for the cool video, you can actually really see how well the dispersion matches up to DCS if you slow it down to .25 speed on YouTube, thanks for sharing.

 

[nighthawk2174]

I did and the circle you drew also includes the smoke cloud, you have to look at the impact flashes not the resultant debre cloud.

[NineLine]

Hmmm, I see flashes in my circle. Some gets obscured by the reticle, but if you watch it slow enough you see it.

[nighthawk2174]

Yes and the area they occupy is quite small, not much bigger than the dot in the circle of the reticule.

[NineLine]

Yes and the area they occupy is quite small, not much bigger than the dot in the circle of the reticule.

 

Well, I have to disagree, you might want to watch it again. If you look at my image, there are two clear flashes near the bottom of my circle, quite a bit wider then the blue circle you drew.

[Exorcet]

The first pass seems to wander a bit and is obscured by the reticule. There is another at around 4:30 that's more stable (though more gun vibration in the footage) and the impacts seem pretty tight.

[nighthawk2174]

Ok so i've done an analysis of the last strafing pass, thanks for pointing that one out Exorcet.

 

 

Now he begins firing a little over .4NM and finishes at just under .2NM. Now when we see the flashes from his final few rounds he is under .1NM. Now replicating that in game:

 

At .2NM the pattern looks like-

Now when we move in closer to match the video (under .1Nm) the pattern looks like-

-also take note i'm actually a bit further away than in the vid, only a little bit but at these close ranges that can impact this.

 

So when we overlay the two we get:

-Red DCS

-Blue Video

 

With the blue circle being based off of 5 frames overlayed together

 

 

-Note lines are to allow me to line up the images

 

 

[NineLine]

Am I still not sure what you are showing, while I agree the second run seems smoother, it also doesn't show as many flashes so I am not sure this is very scientific, and where are those shots being fired from the A-10 in-game that are making this large red circle?