[VEWY INTERAST] Gun acoustics still sound too low rate of fire.

[DmitriKozlowsky]

This is my reference.

[Dr Zaius]

Interesting, it looks like the squeeze of the gun trigger sets a mark point for the targeting pod!

[RAZBAM_ELMO]

Very interast, we are definitely looking at improving the harriers sounds, first ive seen of this video

 

[Tyrant07]

I'd also like to point out the pattern of impact n that video. Notice how its kind of spread and not a straight line laser like we currently have.

[Dr Zaius]

8 hours ago, Tyrant07 said:

I'd also like to point out the pattern of impact n that video. Notice how its kind of spread and not a straight line laser like we currently have.

Yeah I think the gun does need a little spread, shame this clip doesn't clearly show the engagment range.

[RAZBAM_ELMO]

Its difficult to tell too if this is just labelled as a GAU12 or if its something different. Quite a few TPOD data things that we dont have on the Gen4

[Fri13]

On 2/5/2021 at 1:34 PM, Dr Zaius said:

Yeah I think the gun does need a little spread, shame this clip doesn't clearly show the engagment range.

Range is at the bottom of the video. 3000 ft and counting.

[Fri13]

On 2/5/2021 at 4:45 AM, Tyrant07 said:

I'd also like to point out the pattern of impact n that video. Notice how its kind of spread and not a straight line laser like we currently have.

 

The range when gun was fired is 3100-3200 feet (950-975 meters). And on that moment the TPOD crosshair line is 24-23 meters, and end of the firing it is 20 meters.

The spread pattern is clearly around 40 meters wide.

 

Here are the frames from the video.

 

1. On the moment the TPOD manages to turn on the terrain to show its range _3059_ feet, before that it is just about 3200 when pointing straight.

2. The 20 meter line width (for easier scaling)

3. The dust clouds from impacting TP rounds.

 

 

So right now we have a laser cannon in the AV-8B Harrier, if we can trust that video is from a AV-8B Harrier, and that Target Practice rounds gives same spread.

It should mean that we should have ~ 45 meters spread at 1000 meters.

Right now we have about 3-5 meter spread at 4500 ft (comparing to the visual scaling in DCS when firing at BTR-80 that is 7.7 meters long).

 

Comparing it to example Hornet or A-10 or basically any other, the GAU-12 is way too accurate as those others has large spread.

If we would place a BTR-80 inside that, it would be this size:

 

 

 

 

Edited February 23, 2021 by Fri13

[Dr Zaius]

This is a good watch and gives you some sort of idea how accurate the gun was in many of the tests carried out:

 

 

Edited February 25, 2021 by Dr Zaius

[Fri13]

14 hours ago, Dr Zaius said:

This is a good watch and gives you some sort of idea how accurate the gun was in many of tests carried out:

 

By the specs the GAU-12 should have same accuracy as GAU-8, so 5 mil circle with 80% rounds hitting inside it.

In that video we don't know the ranges and other parameters as I recall from couple years back I saw it few times. 

 

So for the specs side, GAU-12 should be firing at 1000 meters (3300 ft) so that 80% of the rounds hits inside 12 meters circle. The BTR-80 is 7.7 meter long, so it will be almost twice the length where 80% of rounds would go.

 

But, if we go with the assumption that video OP posted is real thing, then the firing starts at about 3200 ft mark, the spread is about 45 meters with 66 shells impacting in that whole area, the 80% of the area of that is about 32-36 meters (for 40-45 meters circle) and hence one BTR-80 would fill 1/4 of the firing area. And it suddenly does so. 

 

The TPOD video shows the range to the target. It shows the scale of the target area. And it shows even the spread pattern in that area. But we can not be 100% sure that it is GAU-12, and we need to just assume that Training Projectiles used in the video would have same accuracy as the normal ones, but it wouldn't make sense to give for a training purposes a far more inaccurate ammunition when purpose is to learn to fire the gun and hit with it, or does it? We don't even know that is that video from a damaged gun that is being tested for its adjustment for specification or what....

 

 

[Holbeach]

From video.

 

Manufactures recommended profile to pierce a medium tank armour, with GAU 12U cannon. 5 deg dive, 500 kts, shoot at 3000', stop at 2000', to penetrate 2.5 inches.

 

Gun is engineering test unit.

Ammo is API U. Harrier has fixed sights.

 

..

Edited February 25, 2021 by Holbeach

[Dr Zaius]

I don't think TP rounds are as accurate and I believe that's what we're seeing in the original video + a slightly further engagement range - TP muzzle velocities are generally quicker and I think that's due to them being a lighter (cheaper) round, in particular when compared to denser/heavier/slower rounds like API (DU/tungsten). In terms of it not making sense to train with a round that varies so much in accuracy I don't think there's much you can do about it, the pilot still gets to employ the gun against a target, which is invaluable and any inaccuracies due to the nature of ammo being used can easily be accounted for by the ranges 'score checkers'.

[Fri13]

3 hours ago, Dr Zaius said:

I don't think TP rounds are as accurate and I believe that's what we're seeing in the original video + a slightly further engagement range - TP muzzle velocities are generally quicker and I think that's due to them being a lighter (cheaper) round, in particular when compared to denser/heavier/slower rounds like API (DU/tungsten). In terms of it not making sense to train with a round that varies so much in accuracy I don't think there's much you can do about it, the pilot still gets to employ the gun against a target, which is invaluable and any inaccuracies due to the nature of ammo being used can easily be accounted for by the ranges 'score checkers'.

 

From a unclassified Budget Line Item Justification report from 2019 Air Force:

 

"-25MM Target Practice (TP), PGU-23/U (A978): 25MM PGU-23 is a target practice round used in the GAU-12/A gun systems applicable to the F-35 and AC-130/U aircraft. The round is also a kinetic energy combat round used to limit collateral damage potential. Air Force procures 25MM through the Single Manager for Conventional Ammunition (SMCA), Department of the Army. "

 

There is a newer PGU-33 caliber:

25mm PGU-33/U TPF-T Target Practice Frangible-Tracer (gd-ots.com)

"The 25mm PGU-33/U TPF-T replaces the standard steel PGU- 23/B TP. It is compatible with the NATO 25mm gun systems and is a ballistic match to the PGU- 32/U Semi-Armor Piercing High Explosive Incendiary- Tracer and the PGU-20/U API combat cartridges."

 

And the old one is TP (PGU-23) Target Practice (globalsecurity.org)

"The PGU-23 TP is a low-cost, untraced target practice cartridge, ballistically matched to the PGU-25 HEI round. It complies with NATO STANAG 4173 and can be fired from any system using the M242, KBA, M811, or GAU-12 weapon."

 

 

And then about other kind ammunition in PDF: 108104_04.qxp (alternatewars.com)

 

So simply put, the Training Practice shells are ballistically same as the combat ammunition, so not going to cause wider spread because of that.

And again it would be completely illogical to use a training rounds that does not allow pilot to hit where aimed, rendering the whole exercise moot as what matters is the hits, not where a gun cam shows.

 

The TP round is not just for a training, it is as well for a combat use, to minimize the collateral damage. So you are not going to put for a such task a round that will spread wider area if you are trying to avoid collateral damage.

[Marsvinet]

Those specs for the accuracy GAU-12, do they include the mounts? The A-10s gun mount is possibly the most rigid and sturdy there is, whereas I can bet there is a bit more shaking going on when firing the podded GAU-12 mounted on the belly of the relatively light Harrier airframe.

[Fri13]

11 hours ago, Marsvinet said:

Those specs for the accuracy GAU-12, do they include the mounts? The A-10s gun mount is possibly the most rigid and sturdy there is, whereas I can bet there is a bit more shaking going on when firing the podded GAU-12 mounted on the belly of the relatively light Harrier airframe.

 

Good question.

 

When the GAU-8 is mounted to the...... The airframe is mounted to the GAU-8, it makes a very sturdy coupling.... But is it so much worse in the GAU-12 that is mounted on the external pod, that is attached to bottom of the airframe, that it would be so wide spread? The GAU-12 is a smaller and lighter gun compared to GAU-8 so it shouldn't require so hard mounting.

 

At 1000 meters 80% rounds impacting 5 mil circle is a specification that is very difficulty to get matching to that video. Its firing rate surely is much slower in DCS than in that video, but still it is said in video that they shot only 66 rounds, that sounded more like a 200.

 

But it is difficult to really match that video when specification and results are so far apart. Okay, 80% of the 66 rounds is that 53 should have impacted inside the 5 mil radius. So 13 shells impacting outside of it, what makes it visually look larger, while it can very well be that those 53 did impact inside a 12-14 meter radius (twice the BTR-80, but.... it doesn't look so tight at all. As if we look the line of the cross marking 20 m length, it should be 2/3 of that area.

 

That is why I can't do anything else than really believe that gun was not mounted properly, that there is some kind malfunction that is reason for testing etc. Like that is a test video of the problem for the ground crew to adjust the gun. Instead an actual training for target shooting.

 

But what is sure is that it is not suppose to be so streamsniper as it is now in DCS. That from 3000 ft (900 m) you shoot so tight group that it will split a BTR-80 (7.7 meter long).

The specs diameter is 78% of a twice the length of a BTR-80. So if two BTR-80 ere put in line, 80% shells should impact just little inside the area that is covered from 1000 meters.

Not now at all. It is like 10% of the spread there should be.

 

I just tested the gun spread by following the ELMO required process (8000 ft 350kts, start at 10 nmi, turn 30 degree left/right at 5 nmi, when target reach the inner edge of the canopy, pull as hard possible toward the target for dive.) and even at 0.9 nmi (on moment the gunsight starts to open) that is about 5300 ft (1600 m) SLANT, the GAU-12 has spread of about 4-5 meters, and if firing all ammunition then some shells might hit at 5-7 meters circle, but majority hits well inside 4-5 meters.

 

That is a 165% range from the specs, and spread is about 33% of the specification (1000 meters (3300 ft), 80% inside 5mil - 12 meter circle) already at that range, so we are likely talking about 15-20% of the spread GAU-12 really should have.

 

Can't attach a trackfile to it as it gets broken all the time (live play shows pipper is on the target, shells fly about 5 meters high the target and none hits the target. Track replay shows pipper is 50 meters above target, all shells fly way above the target. Tacview shows that almost all the shells impact the target (edit: of course because HE splash damage....but otherwise matches the Live Play) but it should be repeatable by anyone with latest Open Beta.

 Comparing this to example M61 Vulcan in a F/A-18C Hornet, it has by specification a 8-mil 80% spread. And comparing the Hornet to Harrier in DCS, the Hornet fire a far more proper spread that covers the whole area of the vehicle, while the Harrier is a sniper where you don't just choose do you hit left or right part of the vehicle, but what wheel do you plan to shoot out.

 

Does that look like a 5 mil 80% spread from a 165% the distance as specified for 12 meters (20% of the rounds should impact at 1000 meters outside of 12 meter circle. That is 1650 meters.... Against 7.7 meter long BTR-80)? As at that range 80% hits should be in 19.8 meters, the two BTR-80 has 15.5 meters in total length.

 

Comparing to that YouTube video about spread, it is ridiculous for what DCS has, as well very odd what the video has, but it is very difficult to challenge that video if it information is correct, but many things are unknown for it.

 

 

 

Edited February 26, 2021 by Fri13

[Enduro14]

100 percent agree, the gau12 needs some spread in the shot group.  Hope they run it by their SME and get some adjustments done.