Gunnery totally strange

[scorpac]

Hello all,

do you have the same Problem?

When you pull up or down or left and right and shoot while doing that, even if you move soooooo slowly, the guns totally shuut up down left or right so its impossible to aim

[Luffe]

Could this have something to do with the auto rudder function?

I don't have COD yet, but I have seen 3 different settings, on screenshots, for it in the keysetting.

[Wurschtie]

Try a lower sensitivity setting for the ruder. Of course, aiming with the bird is not easy. It requires practice. Even yawing slightly has a huge effect on where you're firing. A 5° yaw away from the target is a miss of dozens of meters on a target that is 300 meters away.

Practice. You will be getting better.

[Herra Tohtori]

Fluid dynamics in ballistics 101...

Ok here's the brief run-down of what I think is going on, based on what you wrote:

Any object going through air experiences a multitude of forces upon them, bullets are no exception and in fact due to their high velocity and small mass, the aerodynamics are quite complicated (air tends to become quite viscous at such high velocities, as an example).

Not only do they experience high drag, but the airflow can also exert sideways forces on them.

The biggest issue here is the Magnus effect (http://en.wikipedia.org/wiki/Magnus_effect). It is essentially the same phenomenon that causes the curve in a curve ball on football, tennis or what have you.


Magnus effect is caused by the rotation of an object traveling through airflow. The rotation causes situation called circulation (http://en.wikipedia.org/wiki/Circulation_%28fluid_dynamics%29), which makes the rotating object behave analogous to an aero foil - lift force is exerted upon the rotating body.


Bullets rotate very fast due to the rifling of the barrels, so if they travel even the least bit sideways through air, they can experience very high sideways lift forces that can curve their paths quite a bit.


When your airplane is traveling forward at low angle of attack, the guns are fixed to point forward as well - meaning the bullets will travel roughly against the airflow. When you are pitching up or down, or yawing left or right, your airplane points in a different direction than where it is going (heading and velocity directions are not the same). This means that your guns now shoot slightly sideways into the airflow, and your bullets will experience Magnus effect, curving their trajectories in unpredictable fashion and increasing their drag.

This effect was in fact so significant as bomber aircraft got faster and faster that shooting to the side, or directly up or down caused the bullets' trajectories to curve so drastically that it was practical impossibility to actually hit targets that way. Fighter pilots (those who lived) quickly noticed this and approached their targets from above, below or the sides, as the gunners were much less effective that way compared to frontal assault or shooting from 6 o'clock position. The bombers countered by flying in larger formations...


Now, not having seen the issue in-game, I can't say if it is in fact the ballistic simulation of Magnus effect that is causing you to miss, but I did hear they supposedly upgraded the ballistics quite a bit. Maybe this is one of the improvements?

Don't take my word for it, it could be a glitch as well as accurate simulation. Wait for a dev to give you an answer directly from the horse's mouth, when they have time for it.


Incidentally, this is one of the reasons so many tanks use smooth-bore barrels on their main guns as opposed to rifled guns. Smooth-bore barrel does not give the benefit of stability to the projectile, but on the other hand it is much less affected by wind for reasons I specified above. Stability of the projectiles can be achieved by other means than rotation from the rifling, after all (SABOT rounds have flechette-like projectiles with fins for stability, for example).

[Shrike_UK]

i've watched quite a few youtube vids, it appears all ive seem have this issue but no-one complains, but then most are using arcade settings.
some have speculated it might be an auto aiming 'feature' as the plane is flying straight and level but the guns shoot off to the sides like they are try to shoot lead (lead as in intercept path)
hope it can be switched off.

[esmiol]

maybe that come from the setting who make move you head with movement of plane...because of that you may think that your visor and you are in the axe of plane...and in fact no.

but it is possible that ballistic is improve on COD compair with il2 because look the bombs falling.... they never more fall like in il2. they are balanced and dispercing.

like i said to myself....."learn again to shoot in COD man"

[Biggs]

Hello all,

do you have the same Problem?

When you pull up or down or left and right and shoot while doing that, even if you move soooooo slowly, the guns totally shuut up down left or right so its impossible to aim

NO i noticed it too.... they "point" with your movements... its not like last game where the dot was EXACTLY where ur bullets were gonna go... NOW its like the bullets will go where your last movement before you fired was...IE: if you give it left rudder right before you fire... ur bullets will be LEFT of the dot...if you rudder right, just before firing, ur bullets will go RIGHT of the dot...

its a new way of having to think about aiming...

you have to STEER your bullets now...

I almost fell like its a bug.

Go ahead and give it a try, take a hurri out against a bomber or something (with lots of tracers so u can see).. its very odd

[Biggs]

Bump...

Anyone else notice this problem?

[Biggs]

Im bumping this again... This is a very serious issue... and should be the first gameplay bug to be addressed!

I did a gun test (with a Hurricane) and its absolutely comfirmed... the gunnery physics are wrong/bugged...

when you apply rudder while shooting the bullets do the exact opposite of what they SHOULD be doing...

If i rudder to the right the bullets SHOULD fall to the LEFT of the aim point. And if i rudder to the left the bullets SHOULD fall to the RIGHT of the aim point.

However in the game, when i rudder to the right the bullets 'magically' defy the laws of physics and actually move out AHEAD of the aim point to the right!!!!

HOW IS THIS POSSIBLE!? How are the guns "turning" faster than the plane is traversing?

This has completely ruined the gunnery aspect of the game. which is one of the main points of a COMBAT flight sim, if im not mistaken.

--- for all of you not sure what im talking about ... take a hurricane out, fly in 'wonder woman' mode.... hold down the trigger and then apply rudder.... the bullets will magically 'turn' in the direction you are apply rudder to.
making deflection shooting completely FUBAR!

[ZaltysZ]

It is graphical bug.

[Biggs]

It is graphical bug.

how do you mean 'graphical'?... as its effecting the bullets physics.

this is an error in the coding of the physics not just some graphic issue.

[David Hayward]

Biggs, do the "bullets" that have already been fired actually change direction when you hit the rudder?

[Biggs]

Biggs, do the "bullets" that have already been fired actually change direction when you hit the rudder?

no... how can i say this... its as though the stick and rudder movements directly affect the aim of the guns... basically... not only does the rudder change the YAW of the plane... it also "pivots" the guns in the direction you are yawing...

A senario: Im in hurri (or whatever) and i have a me 110 in range (dead ahead, no deflection needed) and just off to the left of dead center bullseye... I naturally would rudder left and get him in my center... now if I do this WHILST firing, the center aim would reach the target BEFORE my bullets do.. thus I would have to swing teh center aim point across the target for my bullets to hit him.... now IN THE GAME in teh same senario when I yaw left whilst firing at the same time, the bullets actually aim to the LEFT of center aim and will hit the target before the center aim point has reached the target

its as though there is a tiny little man in each wing turning the guns towards the target when I apply rudder. I apply a little left rudder, he turns the guns to the left a little.

this effect also applies to the stick but to a less severity... (whilst firing) I pull back on the stick and my bullet go up above the center aim... I pitch down and the bullets go below

the reflector sight and the guns are FIXED OBJECTS to the plane... they shouldn't act independently of each other (christ, thats the whole point of having a reflector sight in the first place. to show where your FIXED guns are aiming at.)

[David Hayward]

It almost sounds like the algorithm used to determine which direction the aircraft is facing is different from the one used to determine where the guns are pointed.

Does it happen for every aircraft type?

[Biggs]

It almost sounds like the algorithm used to determine which direction the aircraft is facing is different from the one used to determine where the guns are pointed.

Does it happen for every aircraft type?

yeah it seems like the algorithm is reversed or something... Its odd because if ur just flying the plane the bullets still have the correct physics they drop as they should its just when you make inputs on the control surfaces that the aiming gets all wonky.

Im sorry to say but i cant confim that all planes do it... ive only been flying spits and hurris...

Ill take a 109 out right now and check to see...my guess is yes though.

[David Hayward]

Try the same thing from an external view. Do the guns fire to the left of where the aircraft is pointed when you hit left rudder?

[DB605]

I just had my first fight in COD and i noticed same weird problem. Unfortunately
with 109 too.

[ZaltysZ]

Its odd because if ur just flying the plane the bullets still have the correct physics they drop as they should its just when you make inputs on the control surfaces that the aiming gets all wonky.

It was posted on sukhoi.ru, that tracers, leading the sight the moment you push the rudder, is a graphical bug, which will be fixed in upcoming patches. Supposedly bullets already have correct trajectory and will hit the target where they should.

I have tested the "leading" bullets against the stationary ground targets and can't say there has been any lead, except the incorrect tracers.

[David Hayward]

They should be able to fix that pretty quickly.

[Meek]

I have experienced this too, however, I'm quite ignorant about ballistics and WW2, so I'm especially ignorant about WW2-era ballistics.

I assumed it was because of the movement of the aircraft, it slightly "slinged" the bullets in the direction of the yaw, kind of like an incredibly weak (with effects visible at range) Wanted-esque bullet curving.

Dunno if it's realistic or not, that's just what I made of it.

[Biggs]

Im not sold on it just being "graphical" there have been several instances where the bullet stream missed completely do to this issue... if your saying it didnt mess with teh physics of it then i should have definitely got hits.... Im talking about closer than .20 away and time slowed by 1/4, theres no way you can miss... yet the bullet stream looks to have missed.

[TheGrunch]

Did no one read Herra Tohtori's post? It's about the effect of relative wind on the bullets. If you're not in co-ordinated flight they will go further in the direction of slip because the relative wind hits the side of the bullet.

[David Hayward]

Biggs, do you see the same thing from the external view?

[Biggs]

Biggs, do you see the same thing from the external view?

yep

[baronWastelan]

Did no one read Herra Tohtori's post? It's about the effect of relative wind on the bullets. If you're not in co-ordinated flight they will go further in the direction of slip because the relative wind hits the side of the bullet.

Sounds great to me! Can you setup a wind in FMB, say 100 MPH, and fire while sitting still on the ground and see the effect that way? I suppose you could man a side gunner position on a bomber in flight and see the deflection that way, if such a position is available to the player ;) He 111 maybe??

[TheGrunch]

Not sure! I'll try and have a look later. :)

[Biggs]

its not that magnus affect stuff.. its just bad coding...

[David Hayward]

That doesn't sound like a graphics issue, that sounds like a problem with the algorithm that determines where the guns are aimed.

[kingpinda]

Anyway... I believe shooting with your rudder is bad form anyway. Well not persé bad form but inaccurate nonetheless. So many things to take into consideration. Ussually you do a dirty rudder spray if you are about to lose your target. Better a badly shot dead target than a pissed target behind you.

Best way to be sure the bullets hit home is to step on the ball. keep the plane straight and use airelons and elevator corrections.

Maybe a tad of topic but thats probably why i havent really noticed what ya'll talking about here.

[David Hayward]

If the difference is due to relative wind speed you might be able to see the path pf the tracers curve. If that's the case it's probably difficult to spot.

You might be able to tell by comparing the offset at high speed to that at low speed.

[David Hayward]

It seems like it would be pretty tough to screw up the direction the guns are pointed, so this is probably intentional. Another way to tell is fire the He-111 nose gun offset to the direction of the aircraft.

[TheGrunch]

its not that magnus affect stuff.. its just bad coding...

Your evidence for this assertion...?

[Biggs]

Your evidence for this assertion...?

If YOU actually read MY post you'd see why...

its not an assertion, because the bullets DON'T curve after they are fired... they fly straight as a freakin arrow... its the angle of the guns themselves... they pivot when you apply input to any control surface...

Im not going to repeat myself again... just re read what i wrote earlier..

...

after another few more dogfights im still convinced that its not just a graphic issue... I wish i knew how to post vids so that i can show u what im on about..

its really ruining any chance of precision deflection shooting. being able to hold lead on your target whilst firing is damn near impossible now. :evil:

And you need all the time on target as possible with these .303s lol

[TheGrunch]

Sorry Biggs, you're absolutely right. I don't usually load tracers so I didn't see just how severe it was. (I just thought I was crap at aiming :rolleyes: )

Best way to see this:


Choose Cross Country Quick Mission
Take a Hurricane
Choose Unlimited Ammo
Start the engine
Throttle up
Hold the gun button
Alternate between left and right rudder

[Biggs]

Gunnery is hard enough as it is... This bug just makes it twice as hard ...

Its the most frustrating thing in this game to try and drag your fire across an enemy plane in a perfect deflect shot, only to have your bulletsswing wildly out in the direct of your rudder movement...Every rudder correction turns into instant OVER CORRECTION!

You end up missing the target altogether... Hundreds of bullets wasted.

[David Hayward]

Is the problem worse when you are going fast than when slow?

[Flanker35M]

S!

Noted the same, guns point to whatever..to make it even worse put head shake on :D

[Feuerfalke]

I noticed the same. It looks as if you have to wait a second until the guns aim in the same direction you're flying at.

You saw a similar effect in some beta-videos.

[IvanK]

Err are we talking Lateral Trajectory shift here ? Trajectory shift can occur in both pitching plane (also called velocity jump in US terms) and the horizontal plane. Vertical trajectory shift is AOA Muzzle velocity and TAS dependent and adds to the lead requirement. Lateral trajectory shift is dependent on Slip/skid angle TAS and Muzzle veloctity. Firing in balanced flight is the most desired option.

[Biggs]

Err are we talking Lateral Trajectory shift here ? Trajectory shift can occur in both pitching plane (also called velocity jump in US terms) and the horizontal plane. Vertical trajectory shift is AOA Muzzle velocity and TAS dependent and adds to the lead requirement. Lateral trajectory shift is dependent on Slip/skid angle TAS and Muzzle veloctity. Firing in balanced flight is the most desired option.

I dont know what it is but id certainly doesnt feel like its some "advanced" bullet dynamics" it feels like an aiming bug. If i yaw or slip to one side my buulets shouldnt be leaping out in front of of the center aiming point, since the guns are fixed to the wings which are fixed to the fuslage which has a reflector sight fixed to it in the cockpit... Get what im sayin here?

Never once did any of the older Il2 versions have this issue.

[ZaltysZ]

4. FM and ballistics. We have already addressed the issue where rounds appeared to leave aircraft sideways. This was caused by the difference between physical and rendered position of the aircraft, i.e. the rendered position lagged behind the actual aircraft position.
Our aircraft programmer has a huge bucket list of things to check, which he’s going over at a rather brisk pace.

... (forum doesn't allow to post only quote).

[Biggs]

... (forum doesn't allow to post only quote).

thanks for that... doesnt really say if its only a graphic issue tho, but hey im glad they are aware of it.

[TheGrunch]

+1

[JG14_Jagr]

Its important to remember that the "bullets" you see are not real. There is a math/physics model that determines where they hit, and how they perform, and then there is a graphical representation to give you the eye candy..they are NOT related or bound together by any physics.. if the "tracers" look wrong it does not mean the bullets are not impacting where they should..

[Biggs]

Its important to remember that the "bullets" you see are not real. There is a math/physics model that determines where they hit, and how they perform, and then there is a graphical representation to give you the eye candy..they are NOT related or bound together by any physics.. if the "tracers" look wrong it does not mean the bullets are not impacting where they should..

I dont think thats true... if you go by what Luthier said, the bullets are in fact "correct" .. its the rendered model of the plane that is "lagging behind" ie" the plane(with the reflector sight in it) is lagging behind.

In the fix, the rendered and physical model will match up thereby fixing this wierd gun-pivot we are experiencing.

[Ernst]

I am not certain if i understand your complain or if i am talking about the same thing. But if i understand its not a bug its realistic. Remember before the firing the bullets are travelling with your ac and they have a component due to velocity vector too when they are fired. When you use rudder right before firing your ac is skidding, i.e, velocity vetor its not the same of your nose. The ac is travelling a bit in the diagonal.

Then, when the bullets come out your guns it had a component in the direction of the nose (due to the gun) and component in the direction of velocity vector (due to velocity vector, this when the plane is skidding is not the same than the direction of the nose), then your bullet is "skidding" too. That case the better is not to skid your ac while shoting or if you need to you have to overcorrect your aim, apply a bit more rudder (do not point your aim over the bogey but a bit to its side) and then your bullets ll hit the mark. This case the bullets appears in the pilot view to be going in the opposite direction of the yaw. I suggest you try to do this (overcorrect your aim) if you scored hits then we are talking about the same thing.

Sorry for my bad english, i expect you understand. I remember a video explaining this but i do not remember where to find it.

But i do not understand your complains since this behaviour is already in IL2 1946.

[Biggs]

I am not certain if i understand your complain or if i am talking about the same thing. But if i understand its not a bug its realistic....

nope, its a bug... read this please.



4. FM and ballistics. We have already addressed the issue where rounds appeared to leave aircraft sideways. This was caused by the difference between physical and rendered position of the aircraft, i.e. the rendered position lagged behind the actual aircraft position.
Our aircraft programmer has a huge bucket list of things to check, which he’s going over at a rather brisk pace.

[Blue Scorpion]

Luthier confirmed this is a real issue and is being investigated; it is due to the rendered aircraft being in a slightly different location than the game engine believes it to be at the moment it fires