reported M1 Abrams - Inconsistent Gun Dispersion

[Apocalypse31]

 

1. The in-game M256 Main Gun dispersion rate is unrealistic and inconsistent

2. Gun Site bounces (does not do that in real life)

3. Stabilization should always be on in the Abrams - it turns off when you switch to the Commanders seat.

4. Lasing sometimes not working. 

 

 

Track file with the mission file

Range.trk Range.miz

Edited January 4, 2021 by Apocalypse31

[Apocalypse31]

What it should look/feel like in-game

 

[Northstar98]

Agreed.

 

I could go on for hours about all the stuff CA falls short on, and in terms of stabilisers this is one where it falls short.

 

In DCS not only is the cannon itself stabilised but the sights are as well, and the drive systems for the sights should easily be able to keep up with vehicle motion (like our TGPs for instance). I'm unsure whether or not the gun stabilisation is driven by the main azimuth and elevation drives (for 2-plane stabilisers) or whether they have an independent, high-speed servo (someone who knows better correct me).

 

None of this is helped by the fact that vehicle suspension is completely backwards in DCS (and I'm not overexaggerating here, on flat terrain the tracks/wheels stay firmly planted to the ground and the hull just bobs around randomly with magnitude proportional to speed). That and vehicle physics is pretty lacklustre IMO and leaves a lot to be desired. 

 

Agreed that the stabiliser and FCS system should be enabled by default (maybe with a less obstructive indicator - putting it in the corner with the rest of the information or under the compass would be better IMO).

 

With the rangefinder, I haven't personally noticed it not working, but what does bother me is that the rangefinder doesn't continuously fire and update when you hold the button down, you have to keep keying it over and over again; I have a hunch that the FCS implemented in DCS (called target tracking) only works in one axis as far as I can tell (i.e the target moving left or right), it doesn't take range rate into account, only the gun elevation correction to hit a target at a particular range. This isn't as much of a problem for tanks, but for anti-aircraft guns like the Gepard, Shilka and Tunguska, it's a nightmare.

 

EDIT: It seems when the FCS system is active it the rangefinder is continuously active, regardless of whether or not you're range-finding manually, so maybe disregard that last paragraph.

Edited January 7, 2021 by Northstar98

[Apocalypse31]

2 minutes ago, Northstar98 said:

the fact that vehicle suspension is completely backwards in DCS

I've never noticed this, and now this is going to bother me. 

[Northstar98]

10 hours ago, Apocalypse31 said:

I've never noticed this, and now this is going to bother me. 

 

Yeah, try it out. On newer vehicles the bobbing around is at least sorta animated properly, but on some vehicles (that being most of them) the idler wheels, return rollers and drive sprockets move independently to hull, when they absolutely shouldn't - and it looks very wrong to say the least - on some vehicles, there's even a noticeable amount of clipping with the top of the tracks and the hull.

 

Even on the newest vehicle addition - the ZSU-57-2, the hull bobbing is present (though broadly animated correctly; the drive sprocket, idlers and return rollers do not move independently from the hull, only the road wheels and tracks (which do deform, but it's only facilitating the random bobbing, it's still not a proper implementation of suspension like we have with aircraft) which is a great start - however, the rear road wheel clips through the top of the track.

 

If you drive over a hill, the tracks won't conform to the shape of the terrain, as they should (obviously within the limits of travel).

 

That and track physics in general isn't really there (no neutral pivoting, kinda borked turning, among other things), and if you do turn you'll notice that both tracks always move in the same direction and at the same speed as each other. 

Edited January 2, 2021 by Northstar98

[NineLine]

Good report guys, will dig through and report what I can.

[NineLine]

I reported the rocking motion, it seems to be an issue across the more modern tanks in general as the T-90 shouldnt do it either.

I am looking for good data on dispersion on the gun, so if you have it, it will make it easier to report.

I will report the stabilization turning off changing seats.

And with real units lasing seems fine all the time, it might be something with static units, I will have to dig deeper. 

 

Thanks, keep in mind in the future to keep 1 report per thread so we can easily track individual issues. Thanks again!

[Mad_Shell]

Test in DCS:

target: static Abrams, front aspect (about 8 or 9 m^2), distance 1000m

I tested Leclerc and Abrams with combined arms, and the dispersion made about 5-10% of shots miss while not moving. 

 

IRL, MBTs have a 100% hit chance at this distance for a target that big. Actually if they aim for the enemy turret, the shell would land on the turret, not even the chassis.

A few examples:

- modern Russian and Western MBTs rounds have a MAX dispersion of about 0.2 mrad. That means that the max deviation at 1000m is 0.2m. To miss a front aspect Abrams, you need at least 10 times more...

- In the paper Is There a Tank Gap?: Comparing NATO and Warsaw Pact Tank Fleets (Malcolm Chalmers and Lutz Unterseher, 1988), it is said that a M-47 Patton fitted with a laser range-finder could hit a 2.3 m square target (5.3 m^2) with a probability of 86% at 1000m. This means that DCS MBTs basically have a worse dispersion than IRL WW2 tanks...

 

On the move, it is worse... IRL, Leclerc is known for consistantly landing shots at 3000m while moving at 50 km/h on rough terrain. In DCS good luck doing that with Combined Arms. If we set AI at excellent level, they miss the majority of their shots at that distance.

 

 

Now about the speeds (on flat terrain, in DCS same speed on terrain or on road):

 

DCS Leclerc max speeds: forward: 70 km/h   ;    acceleration 0-32 km/h: ~ 4s    ;   reverse speed: 9 km/h (!)

IRL: forward on road / cross country: 71 / 55 km/h   ;   acceleration 0-32 km/h: ~ 5s   ;    reverse speed: >35 km/h (!)

 

DCS Abrams M1A2 max speeds: forward: 64 km/h   ;   acceleration 0-32 km/h:  ~ 4s   ;    reverse speed: 23 km/h

IRL: forward on road / cross country: 66-68 / 48 km/h   ;   acceleration 0-32 km/h: 7.2s   ;   reverse speed: ~32 km/h

 

DCS Leopard 2 max speeds:  forward: 69 km/h  ;   time to reach max speed: ~ 4s   ;   reverse speed: 25 km/h

IRL: forward on road / cross country: 68-72 / 45 km/h   ;   acceleration: no data   ;   reverse speed: 31 km/h

 

For all tanks, the time to reach max speed is way too low (less than 15s, while IRL it's > 30s).

 

I didn't test all the tanks in the game, obviously, but I expect similar trends.

Edited May 2, 2021 by Mad_Shell

[Mad_Shell]

A few more examples:

Hellenic Tank Trials (2000):

Test 11 : Evaluation of the precision on still target (still; @2000m; target : 2,3x2,3m still; 10 APFSDS).

Test 12 : Evaluation of the precision of firing on the move on still targets (40km/h; same conditions as before).

Test 15 : Evaluation of the precision on still targets by night (still; @1500m; target : 2,3x2,3m still; 10 APFSDS).

Test 16 : Evaluation of the precision of firing on the move by night on still targets (40km/h; same).

 

Results for test 11 + 12:

Tank Abrams M1A2 - 17 hits of 20

Tank Leclerc  - 20 hits of 20

Tank Leopard 2A5 - 19 hits of 20

 

Results for tests 15 + 16:

Tank Abrams M1A2 - 20 hits of 20

Tank Leclerc  - 19 hits of 20

Tank Leopard 2A5 - 20 hits of 20

 

 

Now me in DCS using Combined Arms (note that the target used is bigger than in the Hellenic Tank Trials!) :

Still, target at 2000m (still Abrams front aspect):

Tank Abrams M1A2 - 16 hits of 20

Tank Leclerc  - 16 hits of 20

Tank Leopard 2A5 - 17 hits of 20

 

 

[dimitriov]

48 km/h reverse speed on Leclerc. Totally agree for all you said. Try the Frenchpack v4 for more accurate leclerc (at least for stab and aiming), can't mod the reverse speed.